After doping with TiO2, a much more densely packed pellet with uniformly distributed porous structure is obtained. Changes in surface chemistry and local structure in the bulk are observed, which are believed to contribute to the improved ionic conductivity and higher critical current density of the TiO2‐doped NZSP. Stable cycling performance with reversible capacities based on different Na storage mechanisms are also demonstrated.Seawater batteries (SWBs) have gained tremendous interest in the electrochemical energy storage research field because of their low cost, natural abundance, and potential use for long‐duration energy storage. Advancing a SWB to demonstration projects is plagued by the poor electrochemical performance stemming from the poor interfaces of the solid electrolyte (SE), as well as the structural and chemical instabilities and sluggish ionic transport properties. In this study, the anode compartment of a surrogate SWB is constructed with a Na | SE | hard carbon configuration, and tailored dopants are introduced into the Nasicon‐type Na 2 can tune the structural and chemical properties and electrochemical performances of the Na3Zr2(SiO4)2(PO4) solid electrolyte to meet the requirements for seawater battery applications.TiO Global consensus suggests that the energy transition must rely on higher introduction rates of renewable sources to ensure a sustainable energy future. However, renewable energy sources such as wind or solar are intermittent in nature, and their distribution is less concentrated compared with fossil fuels. Thus, energy storage solutions are pursued to enable the wider acceptance and use of renewable energy sources in residential and commercial buildings, as well as offshore. Although most energy storage solutions suffer from deployment costs and performance issues, certain batteries suffer further from their reliance on critical materials and materials supply chain inconsistencies. Within this context, the concept of a seawater battery (SWB) recently emerged as a potential long‐duration energy storage solution because of the infinite supply of seawater.1 The 3Zr2Si2PO12 (NZSP) material, which has high ionic conductivity as a solid‐state electrolyte, has been proposed as a promising candidate for solid‐state Na batteries. However, solid‐state electrolytes often encounter issues such as dendrite growth and poor cycling, which ultimately lead to the failure of the cell. The failure mechanism is often associated with an unstable interface that can originate from the poor structural integrity, low ionic conductivity, chemical instability of the SEs, poor contact between the Na metal and SE, or a combination of more than one of these origins.The system uses earth‐abundant seawater and its alkali metal ions, such as Na, in one chamber as the active catholyte. The Na ion is transported from the cathode chamber through a ceramic electrolyte membrane into an anode chamber containing hard carbon (HC). The overall electrochemical reaction produces a cell voltage of 3.4 V as the result of the oxidation of the alkali metal ion at the anode and oxygen reduction reaction at the cathode, forming soluble metal chlorides. The system design constantly rejuvenates reactive components, which promises long life in practical cells. An appropriate anode is essential to ensure reversible Na ion storage, and the choice of the organic electrolyte has a great effect on the electrochemical performance and practicality of the SWB. The solid electrolyte (SE), which is the separation layer between the anode and cathode compartments, plays a crucial role because it should not only promote Na transport when being in contact with nonaqueous electrolytes but should also be stable against saline water and act as physical barrier between the aqueous and nonaqueous electrolytes. Nasicon Nathe cell.2 The 2O3 and TiO2 were introduced in the Nasicon NZSP to tune the chemical, structural, and electrochemical properties of the SEs for the SWB. Advanced characterizations were performed to investigate the morphology, porous structure, local surface and bulk properties, and ionic conductivities of the SE NZSP. Electrochemical performance for the pristine and doped NZSP were evaluated in both a Na | NZSP | Na symmetrical cell configuration and a Na | NZSP | HC cell configuration to mimic the anode compartment of the cell. Results show that in the presence of TiO2 doping, NZSP could achieve higher ionic conductivity and enhanced surface stability and local structure. The TiO2‐doped NZSP (Ti–NZSP) also exhibited the highest critical current density (CCD) in symmetrical cells and much better cycling performance in Na | NZSP | HC cells.This study focused on the SE part of the battery as doping materials such as Al2Figure 2O3 (Al–NZSP) and TiO2 (Ti–NZSP) are shown in Figures 3Zr2(SiO4)2(PO4) NZSP as a Na+‐conducting SE material was first analyzed using a powder X‐ray diffraction (XRD) technique. The diffractogram of the material recorded in the 2θ range of 10°–100° is illustrated in Figure 3Zr2(SiO4)2(PO4) material. All peaks are sharp and well defined, confirming the high degree of crystallinity in Na3Zr2(SiO4)2(PO4). Full pattern matching and refinement indicates that the material has a rhombohedral crystal structure with space group R3¯c, as indicated by the labeled peak positions and the magenta indexes below each pattern. The calculated lattice parameters for NZSP, Al–NZSP, and Ti–NZSP are summarized in Table 2 to the pristine NZSP led to a minor modification in the lattice constants without any impurity phases. However, for NZSP with 2% Al2O3, two phases—Na3Zr2(SiO4)2(PO4) and NaZr2(PO4)3—were observed, as well as minor modification in the lattice constants. In summary, densely packed pellets and high crystallinity were achieved for NZSP, Al–NZSP, and Ti–NZSP despite the formation of some pores for the NZSP pellet and some phase separation for the Al–NZSP pellet.The SWB and its applications are schematically illustrated in 2 powder, ball‐milled TiO2–NZSP powder, and the Ti–NZSP pellet  after Al doping, which indicated that the Zr was in a Zr4+ state. However, for Ti–NZSP, the Zr 3d3/2 and 3d5/2 peaks that shifted toward higher binding energies  indicated higher oxidation states were achieved for Zr. In comparison, Na 1s, Si 2p, P 2p, and O 1s spectra for the three NZSP pellets are shown in Figure  For Al–NZSP, no obvious changes in the binding energies were observed when compared with NZSP, since the introduction of Al2O3 led to a separate phase (NaZr2(PO4)3) that is segregated from the parent NZSP with identical (XO4)3 (X = P or Si) clusters. The binding energies for Na 1s, Si 2p, P 2p, and O 1s all shifted toward higher values for the Ti–NZSP compared with NZSP, which can be attributed to Ti doping and associated local structure changes when TiO6 octahedron meets the NZSP lattice. However, no strong evidence was observed of Ti3+ existing on the surface of Ti–NZSP based on the XPS results, which could indicate that a different compound might contain Ti4+ in a different local atomic arrangement, such as a distorted TiO6 octahedron on the surface of Ti‐NZSP.X‐ray photoelectron spectroscopy (XPS) analysis was performed to understand the oxidation states of each element on the surface of the samples. Titanium 2p spectra were collected for pristine TiOet Figure2A. AfteP Figure . The ZirFigure−1, respectively, at 20 °C. At 70 °C, the Ti–NZSP showed a conductivity of 4.20 mS cm−1 compared with 0.83 mS cm−1 for the Al–NZSP and 1.45 mS cm−1 for the NZSP. From the Arrhenius plots of the conductivity measurements, the activation energy for Na ion migration was estimated to be 0.18 eV for Ti–NZSP, 0.23 eV for NZSP, and 0.24 eV for Al‐NZSP. Transport in these crystalline materials is typically dictated by crystal structure, defect chemistry, and mobile charge concentrations. Sodium ions migrate through the tunnels made by the Si–PO4 tetrahedron and ZrO6 octahedron. Titanium doping potentially disrupts the bond lengths in this octahedron and surrounding coulombic interactions, affecting activation energy and the conductivity for ion migration. Relatively similar activation energy of the Al‐NZSP system indicates that the ion transport pathway is potentially similar to the NZSP system, although with lower conductivity owing to potential secondary insulating phases formed (as seen from the XRD patterns). Subsequently, the CCD of the SEs was measured using symmetric Na | SE | Na cells. CCD is a measure of the maximum allowable current density that can be cycled through the SE prior to filament formation. The protocol employed transported a 0.2 mAh cm−2 charge in each half‐cycle between 0.1 and 7.5 mA cm−2 . For symmetric cells, the key changes in the spectra can be broadly described with two behaviors: 1) a sharp increase in the impedance consistent with physical voiding of the Na metal from the solid electrolyte interphase (SEI) and 2) a sharp decrease in the impedance consistent with the formation of filaments within the SE. To visualize this change better over the duration of cell cycling, the 3D spectra was projected on the  plane so the shifts in the real part of the impedance could be easily tracked , a change in the impedance profile was seen for the NZSP and Ti–NZSP system, which might be related to Na diffusion kinetics at the applied stack pressure. Beyond that change, the NZSP system showed a sharp increase in a few cycles followed by signatures of soft shorting. Similar behavior was seen for Ti–NZSP, but it was in later cycles. The impedance spectra are consistent with the voltage polarization profiles observed within the CCD measurements, where a flat polarization is seen for the lower current densities followed by gradual sloping and nonlinear behaviors at higher current densities. Notably, this analysis is purely qualitative in nature and was carried out to assess the relative behavior of the three material systems.The impedance of the symmetric cell was also tracked during cycling at the end of each plating and stripping step. A typical representation of the Nyquist diagrams is shown in Figure n the SE.7, 9Figure6 octahedron. This phenomenon could relate to the hypothesis proposed in Figure 2 standard is at 4972 eV. Thus, peak shift toward lower energy was observed for spot 2 in comparison with the standard sample, which is likely because the coordination of Ti changed from sixfold to lower. Also, the XANES spectra for spot 2 looked similar to a rutile TiO2 standard. Although it is still unclear now what the exact local environment was within the Ti–NZSP structure, the authors know that changes are associated with the TiO6 octahedron and Ti coordination, which are a result of the introduction of TiO2 into the Na3Zr2(SiO4)2(PO4) structure.To further characterize the bulk properties of the Ti–NZSP pellets, synchrotron X‐ray absorption near edge structure (XANES) analysis was performed on the pellet. The penetration depth was ≈12 µm at 4966 eV (Ti K‐edge). From all the spectra that were collected, at least two different Ti local structures Figure5A were  To assess the microstructure of these SEs, synchrotron X‐ray tomography was performed on the sintered pellets. Binarization of the reconstructed images enabled researchers to visualize the porosity distribution in these SEs 2(PO4) and NaZr2(PO4)3 on the surface, and 2) the SEI formation during electrochemical testing when two drops of 1 m NaPF6 in diglyme were added to wet the Na | SE interface. Because of the phase separation in Al–NZSP, the SEI can be kinetically and thermodynamically unstable for Na plating and stripping, which thus explains the poor CCD value obtained for Al–NZSP in the galvanostatic plating/stripping test. XPS was also performed on cycled pellets, and the Zr 3d, Na 1s, and F 1s spectra are shown in FigurePostmortem characterizations were performed on cycled SE pellets. The SEM and EDX results of cycled NZSP, Al–NZSP, and Ti–NZSP are presented in 32 resulted in a much denser SE and a modified NZSP surface with oxidized elements. With Ti‐doping, the ionic conductivity of the Ti–NZSP SE reached 4.20 mS cm−1. A high CCD of ≈2.5 mA cm−2 was realized in the Ti–NZSP in Na | SE | Na symmetric cell configuration. For practical application, the SWB was mimicked with a Na | SE | HC cell configuration, and it demonstrated excellent cell performances based on storage or plating mechanisms. Postmortem characterization results indicated that a much more stable SEI can be formed on the surface of Ti–NZSP. This work has provided engineering solutions toward SEs, which can pave the way for making better seawater batteries in the future.In summary, a Nasicon‐type SE was developed for SWB applications. Without producing a new phase, the introduction of TiO42O3 and TiO2 (Sigma Aldrich) were prepared by ball‐milling the appropriate quantities of the powders. The doping amount of Al2O3 and TiO2 was set at 2 wt%. Pellets of NZSP, Al–NZSP, and Ti–NZSP were made in a hydraulic press at 5 ton at 150 °C. The pellets were subsequently sintered at 1000 °C for 24 h to obtain the final pellets. The pellets were polished through 220 to 2000 and to 3000 grit sandpapers to get a smooth, mirror‐like surface for further evaluation. The pellets used for electrochemical testing had thickness of ≈800 µm and a diameter of 10–12 mm. HC anode  was mixed with carbon black (Super C65) and polyvinylidene difluoride (Solvay 9300) in a weight ratio of 92:2:6 in an N‐methyl‐2‐pyrrolidone solution before being casted onto Cu foil.Nasicon‐type NZSP was purchased from MSE Supplies LLC and used as is for making the baseline NZSP pellets. Mixtures of NZSP with AlThe pristine NZSP powder and the sintered pellets were characterized by powder XRD. XRD patterns were collected using a Panalytical Empyrean Diffractometer using a 60 kV Mo source and 40 mA beam current. The pattern data was collected between 10°and 70° with a step size of 0.01° at room temperature. HighScore Plus software was used to analyze all the results, and the Rietveld method was adopted to refine the XRD data using Jana2006 program package software. SEM measurements of the pristine and the electrochemically cycled pellets were carried out using a Zeiss MERLIN FE‐SEM. The SEM micrographs were collected at a nominal electron excitation of 5 keV. Energy‐dispersive spectrometry mapping of these pellets was carried out at 15 keV and a working distance of 8.5 mm.σ is the conductivity, R is the bulk resistance, t is the thickness of the sample, and A is the sample area. Conductivity measurements were performed between 20 and 70 °C, and the activation energy for the ion transport was estimated from these measurements using the Arrhenius Equation.Conductivity measurements of the sintered pellets were carried out using impedance spectroscopy measurements with silver blocking electrodes. Alternating current (AC) impedance measurements were carried out on a Biologic VSP 300 potentiostat between 1 MHz and 1 Hz with an amplitude of 50 mV. The impedance spectra were fit to appropriate equivalent circuits, and conductivity was estimated using the following equationm NaPF6 in diglyme) to mimic the SWB cell. The cells were allowed to stabilize at 70 °C prior to the initiation of the CCD measurement. The cells were cycled under a fixed protocol wherein a 0.2 mAh cm−2 charge was cycled in each plating/stripping cycle. CCD was defined as the current density where a sharp variation from the planar deposition/dissolution profile was observed. In addition to CCD, some Na | SE | Na cells were also cycled for long‐term plating/stripping behavior. The symmetric cell was subjected to 50 cycles of 0.2 mAh cm−2 electrodeposition and dissolution, 50 cycles of 0.5 mAh cm−2 electrodeposition and dissolution, and 50 cycles of 1 mAh cm−2 electrodeposition and dissolution at a current density of ≈1 mA cm−2.Symmetrical cells of Na | SE | Na were prepared in a coin cell configuration. For this configuration, NA was rolled into thin sheets and punched out to 6 mm diameter disks. Each Na | SE interface was wetted with two drops of Na liquid electrolyte  between 0.005 and 1.5 V. Subsequently, some cells were cycled within the storage region of the HC at the C/5 rate (between 1.5 and 5 mV cutoff). Alternatively, the plating stability of the Na | SE | HC cell was evaluated. After the formation cycle, the cell was allowed to discharge above the storage threshold of HC material (20 h at C/5 with −1 V cutoff). After that discharge, the cell was cycled at C/5 for 5 h between −1.5 and 1.5 V. After cycling, the cells were disassembled inside a humidity‐controlled dry room, and the SE pellets were taken out for ex situ characterization.HC anodes were punched out into 6 mm disks with ≈1.7 mg cm2O3 and TiO2 powders. All ex‐situ XPS were carried out on a SCALAB Xi+ spectrometer (Thermo Fisher Scientific) using a monochromatic Al Kα source operated at 200 W with a 650 µm beam size. The pass energy of the spectra was 40 eV.XPS spectra were collected on the pristine and electrochemically cycled pellets. XPS was also carried out on the pristine Al2. Under these experimental conditions, a single tomography scan took ≈7–10 min of acquisition time.Synchrotron tomography studies of the sintered pellets were carried out at beamline 2‐BM‐B of the Advanced Photon Source at Argonne National Laboratory. For these measurements, 3 mm pellets were separately pressed and sintered with the powders to ensure that the entire pellet could be captured in the field of view. A pink beam configuration was used to enable adequate transmission through the dense materials. In total, 1500 projections were captured during a 180° rotation of the sample with a 100 ms exposure time for each projection. A forward‐looking infrared Oryx ORX‐10G51S5M camera was used with a 2× magnification objective lens. The resultant voxel size was ≈1.7 mm with a field of view of 3.4 × 3.6 mmTitanium K‐edge XANES spectra were collected at beamline 20‐BM at the Advanced Photon Source at Argonne National Laboratory using a Si (111) double‐crystal monochromator, which was detuned to 15% of its original maximum intensity to eliminate high‐order harmonics. The spectroscopic data were collected using a focused beam in fluorescence mode owing to the low concentration of the element of interest (Ti) within the sample pellet. The Rh‐coated harmonic rejection mirror was set to 5 mrad to cut off the high energy harmonics. Energy calibration was performed by using the first derivative point of the XANES spectrum of Ti (K‐edge = 4966 eV) of a metallic Ti foil recorded before and after the measurement.The authors declare no conflict of interest.Supporting InformationClick here for additional data file.


In this context, ammonia (NH3) is now rapidly emerging as a promising hydrogen carrier for the future. This game change indirectly impacts the field of fine chemistry where hydrogenation reactions are widely deployed. In particular, the possibility of performing hydrogenation reactions using ammonia directly instead of hydrogen has become highly desirable but it remains a very difficult scientific task, which we address in this communication. Here we show that the N−H bond of NH3 can be cleaved within cavitation bubbles, generated by ultrasonic irradiation at a high frequency, leading to the in situ formation of a diimide, which then induces the hydrogenation of alkenes. Advantageously, this work does not involve any transition metal and releases N2 as a sole co‐product.With the progressive defossilization of our industry, hydrogen  as a sole co‐product.Ammonia is used as a hydrogen source for the reduction of alkenes to alkanes. The originality stems from the use of cavitation bubbles that act as “microreactors” to break the N−H bond of NH The key step is the in situ oxidation of N2H4 to diimide (HN=NH) which then readily reacts with alkenes yielding the corresponding alkanes and N2 . In situ oxidation of N2H4 to diimide is generally achieved by O2 (or H2O2),[The utilization of hydrazine  is indeed thermodynamically more favorable than the conversion of NH3 to N2H4 (ΔG=16.5 kJ mol−1). As a result, any catalyst capable of activating NH3 will unavoidably, and very quickly, decompose N2H4, making it nearly impossible the deployment of NH3‐based route for the catalytic reduction of alkenes.The possibility to produce in situ a diimide directly from NHk Scheme . The dec2H4 from NH3.3 was activated and converted to N2H4 by ultrasonic irradiation of aqueous NH3 solutions at a high frequency (525 kHz). This technology does not involve any catalyst, the N−H bond of NH3 was cleaved inside cavitation bubbles, where extreme conditions of pressure and temperature exist,2) which then recombined at the gas bubble‐liquid interface, forming N2H4. Advantageously, the bulk solution remained close to ambient temperature, thus limiting the thermal decomposition of N2H4 to N2 and H2O.Recently, we reported an alternative pathway to catalysis for the direct synthesis of N3 as a hydrogen source. So far, ammonia‐borane[3 by electrochemistry3 for hydrogenation of alkenes remains unsolved.Inspired by this discovery, we report here the sonochemically‐induced hydrogenation of alkenes in water by using directly NHia‐borane31, 323 (5 wt %) subjected to an ultrasonic irradiation at 525 kHz. The temperature of the solution was maintained at 30 °C using a cooling jacket . 1‐octene was selected as a model substrate as it is a representative of cheap and non‐activated alkene widely processed on a large scale. Transposition to other alkenes is discussed later. As 1‐octene is not miscible in aqueous NH3 solution, it was deposited on the surface of an activated microporous carbon (DARCO®‐100) (5 wt % of 1‐octene) to facilitate its dispersion in water (Table S1). This strategy was also motivated by the principle of heterogeneous cavitation, i.e. the particles of carbon serve as nuclei for the formation and growth of cavitation bubbles, a mean to maximize the occurrence of cavitation events on the supported 1‐octene liquid phase.[In a first set of experiments, we investigated the hydrogenation of 1‐octene in an aqueous solution of NHid phase.34, 353 (5 wt %) and sonicated at 525 kHz for the desired ultrasonic time. At the end of the ultrasonic irradiation, the carbon was recovered by filtration and washed with dichloromethane to desorb organic products. The dichloromethane phase was then analyzed by gas chromatography (GC) to determine the conversion, yield and selectivity . The 1‐octene/n‐octane ratio was doubly checked by 1H NMR . Pleasingly, under these conditions, 12 % of 1‐octene was reduced to n‐octane within 2 h of ultrasonic irradiation, demonstrating the feasibility of this approach. Extending the ultrasonic time from 2 to 28 h led to a gradual increase of the n‐octane yield from 12 to 93 %  and GC, revealing the high selectivity of this methodology. Under silent conditions (i.e. no ultrasonic irradiation) or in the absence of NH3, no n‐octane was formed and 1‐octene remained unaltered, confirming that the reduction of 1‐octene was a result of the combination of NH3 with high frequency ultrasound . It is noteworthy that a slightly lower yield in n‐octane was obtained when the microporous carbon support was replaced by a mesoporous one (20 % vs 32 %), presumably because part of the entrapped 1‐octene is less exposed to cavitation events in the latter case (Table S1).No other product than d Scheme . After r3 concentration of 5 wt %. Lower concentrations reduced the rate of the reaction while higher concentrations decreased the efficiency of cavitation effects . This results was linked to the decomposition of NH3 which is an endothermic reaction. As a result, when the concentration of NH3 within the cavitation bubbles is too high, the decomposition of NH3 rapidly consumes the energy of the cavitation bubbles, thus limiting the growth and fate of cavitation bubbles.n‐octane measured after 6 h of ultrasonic irradiation. For instance, increasing the 1‐octene loading on carbon from 2 to 23 wt % linearly dropped the n‐octane yield from 36 to 10 % . However, in all cases, yields in n‐octane can be increased by extending the ultrasonic irradiation time over 6 h. This result suggests that the rate of the reaction is controlled by the ultrasonic activation of NH3. Furthermore, addition of radical scavengers such as phenol or sodium benzoate considerably inhibited the reaction suggesting the occurrence of a radical mechanism . Finally, the possible contribution of the metallic reactor wall (Inox 316 L) on the reaction mechanism has been ruled out by compartmenting the solution in a polyethylene flask In agreement with our previous report,3 to N2 and H2, this latter can be further activated inside cavitation bubbles  to reduce 1‐octene  or (2) the in situ formation of a diimide species (NH=NH) which is involved in the N2H4‐mediated reductive process. To discriminate between these two hypotheses, hydrogen was bubbled in a suspension of 1‐octene supported over activated carbon in water and subjected to an ultrasonic irradiation at 525 kHz  a complete decomposition of NHn‐octane was observed, indicating that a reduction with in situ produced H2 is less likely to occur ; in this case a diimide can no longer be formed. As anticipated, in this case, no reaction occurred , suggesting that dissolved air plays no major role in the formation of diimide under ultrasonic irradiation . As expected, at 30 °C under air, 1‐octene was reduced to n‐octane with 22 % yield in the presence of N2H4 (1.25 mM)  by direct recombination of biradical NH species, previously detected by sonoluminescence of aqueous NHlved air,13, 14 by direc3 solution,2O2 was detected in our case which may be rationalized by its rapid in situ consumption, for instance by reaction with hydrazine to form the diimide.[2H4 at the beginning of the reaction, and under Ar to prevent the formation of diimide by oxidation of N2H4 with air. Results were all collected after 6 h of ultrasonic irradiation. Initial addition of 0.7 and 1.3 mmol L−1 of N2H4  did not significantly impact the yield in n‐octane after 6 h of reaction, showing that hydrazine is not the limiting reactant . Formation of hydrazine was observed, at a rate of 0.017 mmol/h, which is about 8 times lower than in the absence 1‐octene supported on carbon diimide.13, 143. Formatn‐octane and N2. It should be noted that no trace of n‐octylamine was detected  indicating that ⋅NH2 radicals, possibly formed by cracking of NH3 inside the cavitation bubbles, reaction of NH with ⋅H radicals, NH with NH3 or ⋅OH with NH3, very rapidly recombine at the gas bubble‐liquid interface to form hydrazine . To our delight, in contrast to air, no nitrites/nitrates (at least below the detection limit (<0.5 mg mL−1)) were detected under argon , indicating that the recombination of NH or ⋅NH2 with ⋅OH radical is less likely to occur under argon. It also indirectly provides an experimental evidence that the amount of water  in the cavitation bubble is probably much lower than that of NH3, a logical result considering that NH3 is a gas.Assuming this proposed mechanism, the recombination of NH or ⋅NHn‐octane (40 %) was obtained  . To do so, the volume of the solution was decreased from 150 to 50 mL (for a same energy input of 21 W), resulting in a concomitant increase of the acoustic power density from 0.14 to 0.42 W mL−1. This increase of the acoustic power density led to an improvement of the n‐octane yield (collected after 6 h of ultrasonic irradiation) from 11 to 68 %, respectively . Decreasing again the volume of the solution below 50 mL was technically not possible with our reactor configuration (due to overheating), but these last results demonstrate that the rate of sonochemically‐induced reduction reaction with NH3 could be theoretically and drastically improved by switching from a batch to a continuous flow reactor. Furthermore, in terms of energy saving, it is also noteworthy that free hydrazine formed into the solution could be advantageously used to speed up the hydrogenation reaction. Indeed, there is no need to push the sonochemically‐induced hydrogenation of alkene to complete conversion, as the in situ produced hydrazine could be further used to terminate the hydrogenation reaction under silent conditions (under air) as shown in Table 3 solution (5 wt %) was stopped after 25–30 % conversion of 1‐octene, there would be enough hydrazine into the solution to terminate, in theory, the hydrogenation of 1‐octene using catalysts such as flavins .[3) to current catalytic processes (for the N2H4‐mediated hydrogenation of 1‐octene) is also a scientific line of thought to advantageously reduce the overall energy expenditure of this technology.The predicted massive electrification of our society now opens opportunities for the research on new technologies such as ultrasounds but also on others like plasma, electrolysis, photocatalysis, γ‐radiation, etc. Although renewable electricity at a competitive price is now available from wind or solar,ure S17).25, 263, the future hydrogen carrier, instead of H2 for the reduction of alkenes to alkanes. This challenging reaction was tackled in this work by applying an ultrasonic irradiation, at a high frequency, in an aqueous solution of NH3. The as‐formed cavitation bubbles act as microreactors for the cracking of NH3 and the generation of a diimide which subsequently induces the hydrogenation of alkenes in water. The absence of metallic catalyst and the release of N2, and partly H2 (which can be possibly both captured and recombined to NH3), as sole co‐products represent noticeable advantages of this technology. Furthermore, the low temperature of the ultrasonic reactor (30 °C) is of high interest in terms of selectivity as no other carbon‐based product than alkanes were formed .In conclusion, this work opens a path for the direct utilization of NH2H4 as a reductant offer opportunities to optimize the energy expenditure of this technology. The Agence Nationale de la Recherche (project JCJC ANR‐20‐CE07‐0006) is acknowledged for financial supportIn terms of perspective, our experiments strongly suggest that switching from a batch to a continuous flow reactor and the coupling of ultrasound with current catalytic technologies utilizing NThe authors declare no conflict of interest.As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re‐organized for online delivery, but are not copy‐edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors.Supporting InformationClick here for additional data file.Supporting InformationClick here for additional data file.Supporting InformationClick here for additional data file.Supporting InformationClick here for additional data file.Supporting InformationClick here for additional data file.Supporting InformationClick here for additional data file.


Neither specific uptake of dopamine and binding of [3H]dihydrotetrabenazine, nor mean values of the calculated ratios of dopamine uptake and VMAT2 binding, a measure of uptake rate per transport site, were significantly different between ILBD and controls. ATP-dependence of [3H]dopamine uptake revealed significantly higher rates in putamen than in caudate at saturating concentrations of ATP in controls, a subregional difference lost in ILBD. Our findings support a loss of the normally higher VMAT2 activity in putamen as a contributing factor to the higher susceptibility of the putamen to dopamine depletion in idiopathic PD. Moreover, we suggest ILBD postmortem tissue as a valuable source for testing hypotheses on processes in idiopathic PD.Incidental Lewy body disease (ILBD) is a neuropathological diagnosis of brains with Lewy bodies without clinical neuropsychiatric symptoms. Dopaminergic deficits suggest a relationship to preclinical Parkinson’s disease (PD). We now report a subregional pattern of striatal dopamine loss in ILBD cases, with dopamine found significantly decreased in the putamen (−52%) and only to a lower extent in the caudate ; this is similar to the pattern in idiopathic PD in various neurochemical and in vivo imaging studies. We aimed to find out if our recently reported impaired storage of dopamine in striatal synaptic vesicles prepared from striatal tissue of cases with idiopathic PD might be an early or even causative event. We undertook parallel measurements of [ However, there is a range of neurological syndromes with striatal loss of dopamine that are distinct from idiopathic PD, such as multiple system atrophy and progressive supranuclear palsy6, summarized as atypical PD. In neurochemical studies on postmortem brains of patients with idiopathic PD, a characteristic pattern of dopamine loss has been found in the striatum with a nearly complete depletion of dopamine in all subdivisions of the putamen and substantial levels of dopamine remaining in the caudate7. With the progress of in vivo imaging methods, this pattern has also been detected in live patients with various stages of idiopathic PD12 and allowed differentiation between idiopathic PD and atypical PD17. Although the incidence of idiopathic PD increases with age, and there is an age-dependent reduction in striatal dopamine innervation18, the regional pattern of striatal dopamine loss in normal aging differs substantially from the pattern typically observed in idiopathic PD19. By contrast, 18F-dopa uptake for asymptomatic co-twins of patients with PD already revealed the typical pattern with a small but significant reduction of the dopamine marker in putamen but not in caudate20.Individuals with Lewy bodies or Lewy neurites at autopsy but without clinical findings of parkinsonism or dementia during their lifetime can be subsumed under cases with incidental Lewy body disease (ILBD). They are considered pre-symptomatic Parkinson’s disease (PD) by their nigrostriatal pathological features that are intermediate between those in morphologically normal control persons and those with overt PD21 and the vesicular monoamine transporter 21. However, all striatal findings are based on analysis of the putamen, and there are neither data on the caudate in ILBD in the literature nor on striatal dopamine tissue levels. We therefore set out for analysis of monoamine neurotransmitter tissue levels in both caudate and putamen of cases with ILBD. In a recent study on postmortem striatal tissue of cases with idiopathic PD, we observed a loss of 56% and 90% dopamine transport efficiency in synaptic vesicles of dopamine nerve terminals in the caudate and in the putamen, respectively22. Therefore, we also performed vesicular uptake on the caudate and putamen of our cases in this presumptive preclinical phase of PD.In ILBD, two neurochemical markers of striatal dopamine nerve terminals have been reported to be reduced, the immunoreactivity of tyrosine hydroxylase25. Whereas noradrenaline and serotonin were either unchanged or insignificantly increased in ILBD . The calculated ratio of dopamine uptake to [3H]DTBZ binding reflects the number of transported dopamine molecules per unit time per VMAT2 transport site, a measure of turnover or transport efficiency. There was no significant difference between the putaminal or caudate tissue of controls and ILBD cases neither in dopamine uptake and [3H]DTBZ binding nor in turnover  since dopamine tissue levels essentially stem from dopamine within synaptic vesicles where dopamine depends on continuous accumulation by the vesicular monoamine transporter. The loss of the higher activity of the vesicular monoamine transporter in putamen than in caudate in ILBD might be an early event in the development of neurodegeneration in idiopathic PD. Since transport was determined by an accumulation assay, differences in energy-dependent storage might, in principle, contribute to the measured pmol/mgprot/min, although the short incubation time of 5 min, aiming at initial rates, makes this contribution less likely. Storage may, however, be a factor in dopamine tissue levels. Findings on reduced NADH-ubiquinone reductase and NADH cytochrome c reductase activities in the substantia nigra45 and down-regulated genes of subunits of the respiratory chain complex I in nigral dopamine neurons47 suggest disrupted energy metabolism in dopamine neurons in PD which might have a higher impact on dopamine in putamen with its higher levels and therefore higher energy-dependence. However, another very recent laser capture microdissection study on neuromelanin-positive cells revealed an upregulation of oxidative phosphorylation pathways in ILBD48, suggesting that reduced vesicular uptake and storage in putamen might be more related to changes in vesicular monoamine transporter 2 or vesicular H+-ATPase.Since active transport into storage vesicles is driven by a transmembrane pH and electrochemical gradient generated by the vesicular H49, activation of NADPH oxidase 250, or LRRK2 kinase51 in tyrosine hydroxylase positive neurons. ILBD postmortem tissue could be a valuable source for testing these hypotheses in idiopathic PD at an early stage with more validity for a causal role in the progression of the disease.In conclusion, although our findings cannot rule out that ILBD is only an associated factor of PD, they give new support to the assumption that ILBD might be a preclinical stage of idiopathic PD. Obviously, this stage is only available for examinations postmortem since it is based on a neuropathological analysis. However, quite a few novel hypotheses about the neurodegenerative process in PD have been tested in postmortem tissue from PD patients, such as the increased expression of the vesicular glutamate transporter52  pathology and Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) scoring of the density of neuritic plaques) and McKeith Lewy body stage53, LBD-related neuropathological findings of the subjects, diagnosed according to the Lewy Pathology Consensus Criteria54 are shown in Table Tissue for this study was provided by the Newcastle Brain Tissue Resource, with full informed consent of donors. Brain tissue was obtained at autopsy and stored within the Newcastle Brain Tissue Resource (NBTR), with the full written informed consent of the donors, in accordance with the Newcastle University Ethics Board . Samples from the midcaudate (head) and midputamen  in 1 M Tris-HCl, pH 8.6, and after washing with H2O and desorption with 0.2 ml 0.1 M perchloric acid containing 0.4 mM sodium bisulfite; 100 µl was injected into a high-performance liquid chromatography system with electrochemical detection (HPLC/ED) with a sodium phosphate mobile phase with l-octane sulfonic acid as described previously55. For determination of serotonin, 3,4-dihydroxyphenylacetic acid, and homovanillic acid, the supernatant was diluted 1:4 with 0.1 M perchloric acid containing 0.4 mM sodium bisulfite, and 100 µl was injected directly into an HPLC/ED system with a sodium phosphate mobile phase with l-heptane sulfonic acid as described previously55.Distinct samples of 20–50 mg from caudate and putamen frozen and kept at −80 °C were ultrasonicated from all subjects with an ultrasonic probe sonicator in 25 volumes of ice-cold perchloric acid, sodium bisulfite, and 3,4-dihydroxybenzylamine as internal standard . For determination of noradrenaline and dopamine, homogenates were centrifuged at 16,100 × 3HDTBZ]-binding from the same preparation, about 140–180 mg of striatal tissue were homogenized in 8 volumes of ice-cold 0.3 M sucrose containing 25 mM Tris (pH 7.4) and 10 µM pargyline, using seven up-down strokes in a glass Teflon Potter-type homogenizer and the whole further procedure was performed at 4 °C. The sucrose-homogenate was centrifuged at 1000 × g for 15 min, and the supernatant was recentrifuged at 20,000 × g for 30 min. The resulting pellet (“P2”) was subjected to osmotic shock by resuspension in 1 ml H2O, frozen for about 15 min, and, after thawing, homogenized in a total of 2 ml H2O. The aqueous samples were centrifuged at 22,000 × g for 15 min, and the osmolarity of the supernatant was readjusted by the addition of 1.3 M potassium phosphate buffer (pH 7.4) in 1/10 the volume. The supernatant of the 20,000 × g centrifugation (see above) was centrifuged at 100,000 × g for 30 min, and the resulting pellet was resuspended in the about 2.17 ml of the 22,000 × g supernatant readjusted to 0.13 M potassium phosphate, thus combining vesicles in the supernatant of the P2 pellet and in the hypoosmotically shocked P2 pellet. After incubation in a total volume of 3 ml assay buffer KP  in the presence of 2 mM MgATP in a 30 °C water bath for 4 min and centrifugation at 4 °C at 100,000 × g for 45 min the resulting pellet was resuspended in 4.8 ml KP. On each preparation, 1.5 ml were centrifuged at 4 °C at 153,000 × g for 45 min, and the pellet was resuspended in 100 µl of binding buffer SP  and frozen at −80 °C until the [3H]DTBZ binding experiment and the rest of the preparation was used for vesicular uptake. Protein content was determined according to the Bradford method by a Bio-Rad assay kit.For performing vesicular uptake and dopamine , various concentrations of MgATP  and 1 µM reserpine for determination of unspecific uptake as described previously22. Transport was initiated by placing the tubes in a 30 °C water bath and adding 0.5 ml vesicle suspension  for 5 min. Uptake was terminated by the addition of 2.5 ml ice-cold KP and immediate filtration under vacuum onto Whatman GF/B filter paper pre-soaked in 1% polyethylenimine using a Brandel harvester. The filters were washed twice with an additional 3 ml of cold KP and, after shaking in a liquid scintillation cocktail at 55 °C for 1 h, analyzed for tritium radioactivity in a liquid scintillation counter.Uptake was performed in a total volume of 1.5 ml KP containing 0.1 µM [22.Binding of (±)-a-dihydrotetrabenazine [2-3H]  was performed on 25 µl thawed preparation in SP at a total volume of 25 µl for 90 min at 30 °C as described previouslyData are reported as mean ± SE. Statistical analysis was done for neurotransmitter tissue levels using two-way analysis of variance for the factors disease (ILBD or control) and region (caudate or putamen) and for comparison of uptake in the putamen and caudate in the various control and ILBD cases using two-way repeated measures ANOVA (two factor repetition) for the factors region (caudate or putamen) and ATP , both tests followed by pairwise multiple comparison procedures (Holm–Sidak method) after data passed the normality test (Shapiro–Wilk) and the equal variance test (Brown–Forsythe).Further information on research design is available in the Supplementary Figure 1Reporting Summary


Chromosome 9 open reading frame 72 (C9orf72) is one of the most dazzling molecules in neurodegenerative diseases, albeit that its role in Parkinson's disease (PD) remains unknown. This article aimed to explore the potential mechanism of C9orf72 involved in the pathogenesis of PD.The expression and phosphorylation levels of C9orf72 were examined by Western blotting, RT‐PCR, and immunoprecipitation using PD models. Multiple bioinformatics software was used to predict the potential phosphorylation sites of C9orf72 by Cdk5, followed by verification of whether Cdk5‐inhibitor ROSCOVITINE could reverse the degradation of C9orf72 in PD. By constructing the sh‐C9orf72‐knockdown adenovirus and overexpressing the FLAG‐C9orf72 plasmid, the effects of C9orf72 knockdown and overexpression, respectively, were determined. A short peptide termed Myr‐C9orf72 was used to verify whether interfering with Cdk5 phosphorylation at the Ser9 site of the C9orf72 protein could alleviate autophagy disorder, neuronal death, and movement disorder in PD models.The expression level of the C9orf72 protein was significantly reduced, albeit the mRNA expression was not changed in the PD models. Moreover, the phosphorylation level was enhanced, and its reduction was mainly degraded by the ubiquitin‐proteasome pathway. The key nervous system kinase Cdk5 directly phosphorylated the S9 site of the C9orf72 protein, which promoted the degradation of the C9orf72 protein. The knockdown of C9orf72 aggravated autophagy dysfunction and increased neuronal loss and motor dysfunction in substantia nigra neurons of PD mice. The overexpression of C9orf72 alleviated autophagy dysfunction in PD neurons. Specifically, interference with Cdk5 phosphorylation at the S9 site of C9orf72 alleviated autophagy dysfunction, neuronal death, and motor dysfunction mediated by C9orf72 protein degradation during PD.Cumulatively, our findings illustrate the importance of the role of C9orf72 in the regulation of neuronal death during PD progression via the Cdk5‐dependent degradation. The theoretical scheme of Chromosome 9 open reading frame 72 (C9orf72) protein involved in neuronal death in Parkinson's disease (PD). During PD, Cdk5 is activated in dopaminergic neurons of the substantia nigra, and the activated protein kinase Cdk5 phosphorylates the S9 site of C9orf72 protein. Phosphorylation at S9 site mediates C9orf72 protein degradation through the ubiquitin‐proteasome pathway. Degradation and loss of function of C9orf72 protein, leading to autophagy impairment in neurons. Proteins such as p62 and α‐synuclein that cannot be effectively cleared by autophagy accumulate abnormally, and their neurotoxicity causes the death of dopaminergic neurons. PD more commonly affects the elderly, with an average age of onset of 60 years.According to recent studies, C9orf72 is closely related to the pathogenesis of neurodegenerative diseases.Past studies have demonstrated that Rab proteins 1, 5, 7, and 11 regulate autophagyIn this study, we noted that the C9orf72 protein expression was significantly reduced in various PD animal and cellular models, accompanied by autophagy dysfunction and the accumulation of autophagy substrates. Further research revealed that the downregulation of C9orf72 expression led to autophagy dysfunction, while the overexpression of C9orf72 led to the activation of autophagy and the promotion of the degradation of autophagic substrates. Numerous studies have suggested that, during PD, Cdk5 is overactivated in the brain and its phosphorylation function is enhanced.22.1+(Lot#134347) were obtained from Sigma‐Aldrich. The antibodies of rabbit polyclonal anti‐p62  and LC3  were purchased from Cell Signaling. Rabbit polyclonal anti‐α‐synuclein (WB‐1: 800) was obtained from Proteintech. Rabbit polyclonal anti‐C9orf72  was purchased from Abclonal. Mouse anti‐tyrosine hydroxylase (WB‐1: 5000) was obtained from Millipore. The antibodies were used at the dilutions recommended by the manufacturers. All WB secondary antibodies  were procured from Jackson ImmunoResearch. All fluorescent secondary antibodies (1:500) were procured from Jackson ImmunoResearch and used according to the manufacturer's instructions. MG132 was purchased from Abcam. 3‐Methyladenine (3‐MA) was obtained from Calbiochem. ROSCOVITINE was procured from Sigma. The antibodies against GFP and Flag tag were purchased from Proteintech.The antibody of β‐actin , MPTP, and MPP2.2The plasmids encoding GFP‐C9orf72, Flag‐C9orf72 WT, and Flag‐C9orf72 S9A were purchased from Brain Case. The plasmids encoding GFP‐vector, GFP‐α‐synuclein A53T, and HA‐Cdk5/Myc‐p35 were owned by our research group. The EGFP‐α‐synuclein‐A53T adenovirus was purchased from BrainVTA. The Sh‐C9orf72 adenovirus (AAV2/9) was purchased from Brain Case. Myr‐C9orf72 protein undecapeptide  and Scramble‐C9orf72 protein undecapeptide (P210824‐LL926655) were purchased from GL Biochem (Shanghai) Ltd.2.3Male C57BL/6 mice (age: 8 weeks: weight: 22–28 g) were used to mimic an acute PD mouse model  2019–0004). The mice received a single intraperitoneal injection of 25 mg/kg MPTP once a day for 10 consecutive days, and 0.9% saline was used as the vehicle. MPTP was administered to 3‐month‐old male C57BL/6 mice (weight: 22–28 g) to mimic a chronic PD mouse model.2.4The neurons were cultured at embryonic days 16–18 from Sprague–Dawley rats on 6‐well plates precoated with poly‐D‐lysine (Sigma‐Aldrich). The primary neurons were maintained in the neurobasal medium (Gibco) containing 2% B27 supplement (Shanghai Biogene Biotech), 0.5 mM glutamine (Gibco), and 25 μM penicillin and streptomycin . After 24 h of plating, the cell division inhibitor Ara‐C was added to the medium at a final concentration of 10 μM to remove the glial cells. All treatments or transfections were performed after 7 days of in vitro plating. HEK293 cells were cultured in DMEM(Lot#8122280) supplemented with 10% FBS and the SH‐SY5Y cells were cultured in DMEM/F12 supplemented with 10% FBS. HEK293, SH‐SY5Y cells and primary neurons were transfected with the indicated plasmids with the Lipofectamine 2000 reagent (Sigma) in accordance with the manufacturer's instructions.2.5For tissue staining, the mice were anesthetized with 5% chloral hydrate and perfused first with normal saline and then with 4% PFA for 8 min. The brain tissues were carefully removed, placed in 4% PFA, fixed at 4°C for 24 h,2.6+ or A53T‐treated neurons for 7 days; 20 μM MG132 was added to the MPP+ or A53T‐treated neurons for 7 days. Then, the neurons were lysed in the RIPA buffer, and the lysate was boiled in the SDS sample buffer for 5 min, followed by being subjected to Western blotting with the corresponding antibodies.1 μM 3‐MA was added to the MPP2.7The midbrain substantia nigra proteins and neuronal cortical cells were cleaved in RIPA buffer  containing protease inhibitors. The lysates were incubated with the corresponding antibodies overnight at 4°C and then spun with protein G plus/protein A‐agarose  for 3 h at 4°C. After washing thrice, the immune complexes were boiled in an SDS sample buffer for 10 min, subjected to SDS‐PAGE, transferred onto a nitrocellulose membrane, and then immunoblotted with the corresponding antibody. The primary cortical neurons were co‐transfected with the Flag‐C9orf72 WT plasmid and Flag‐C9orf72 S9A plasmid, while the HEK293 cells were co‐transfected with HA‐Cdk5/Myc‐p35 plasmid. Next, the cells were treated with MG132 (20 μM) for 24 h. The primary cortical neurons and HEK293 cells were lysed in RIPA buffer (a portion of the lysate was reserved for WB), and immunoprecipitation was performed with the corresponding antibody and protein G plus/protein A‐agarose. The immune complexes were boiled in the SDS sample buffer for 10 min, subjected to SDS‐PAGE, transferred onto a nitrocellulose membrane, and finally immunoblotted with the corresponding antibody. The remaining lysate was boiled in the SDS sample buffer for 5 min and subjected to Western blotting with the corresponding antibodies.2.8The total RNA was extracted from SNpc with the TRIzol reagent (Invitrogen). The total RNA (1 μg) of each sample was reverse‐transcribed using the MonScript™ RTIII 5× All‐in‐One Mix  in a 20‐μL volume. For PCR, the amplification was performed in a total volume of 20 μL containing 0.4 μL of each primer,2.9+, FLAG‐C9orf72 plasmid+MPP+, FLAG‐Vector plasmid+PFF, FLAG‐C9orf72 plasmid+PFF, and FLAG‐C9orf72 plasmid. When the cells grew to 70%–80% confluence of the slide, the cell solution was changed to MEM medium without serum and double antibodies, and the transfection was performed after 2 h. Then, 1.5‐mL sterile EP tubes were labeled “1” and “2”, and 250 μL of the Opti‐MEM was added to each tube, 5–10 μL of Lipofectamine2000 was added to “tube 1” and 150 pM of FLAG‐C9orf72 plasmid to “Tube 2”. The two tubes were left to stand for 5 min, then both tubes 1 and 2 were mixed thoroughly, and allowed to stand for 20 min. The cells were then washed in a 6‐well plate twice with PBS, followed by the addition of 1.5 mL of serum‐free medium. Then, the mixture of tubes “1” and “2” was added to the 6‐well plate gently and uniformly with continuous culture for 6 h. After 6 h, the serum‐free medium was changed to a normal medium (without the addition of a double antibody) and the culture was continued for 18 h. After 24 h of transfection with FLAG‐Vector plasmid and FLAG‐C9orf72 plasmid, the 6‐well plate was removed and 1 mM of MPP+ or PFF was added to each well for 24 h. Each group was designed with 3 parallels. After 24 h, the culture medium was discarded, and the fresh complete culture medium was mixed with CCK‐8 at 100 μL: 10 μL. Next, 110 μL of the mixture was added to each well, and the culture was continued for 4 h. The OD value of each well was measured with a microplate reader at the wavelength of 450 nm. Cell viability (%) = /(control group A–blank group A) × 100%.The experimental cells were grouped as follows: Vector, FLAG‐Vector plasmid+MPP2.10The mice were placed in an open field (50 × 50 × 25 cm) and free to move for 15 min, a video camera was used to record the movement path and total distance of the mice. Keep the environment quiet during the experiment, so as not to frighten the mice and affect the experimental results, and repeat the test every 2 days. At the end of each mouse's test, the feces and urine of the mouse were cleaned, and the field was sprayed with 75% alcohol to eliminate the smell of the previous mouse.2.11Mice were placed on the roller in turn, and then the speed of the roller was gradually adjusted to 30 rmp/min at an acceleration of 0.3 rmp/sec, and the time from the start of the roller rolling to the drop of the roller was recorded. Mice in each group were tested for 5 times, with the maximum value of 5 min each time, and the average value was taken as the final test result. The mice would crawl around on the roller, and as the speed of the roller increased, the mice eventually lost their balance and fell off the roller, and stop timing at this point. The apparatus was cleaned with ethanol between each test.33.1To determine the involvement of C9orf72 in the pathogenesis of PD, we measured the expression of C9orf72 in 3 PD models with the environmental factor 1‐methyl‐4‐phenyl‐1,2,3,6 (MPTP), genetic factor α‐synuclein A53T, and preclinical factor recombinant α‐synuclein PFF. In MPTP‐treated PD mice, we noted decreased C9orf72 protein content in SNpc, dysregulated autophagy, and the accumulation of autophagic substrates Figure ; moreove3.2+)‐exposed neurons and SY5Y cells, both of which indicated a decreased C9orf72 expression and the accumulation of autophagy substrates , which competitively inhibited Cdk5‐dependent Ser9 phosphorylation in C9orf72. This peptide was conjugated to myristic acid to ensure its cell‐penetrating ability. Unsurprisingly, the Myr‐C9orf72 peptide effectively protected MPPh Figure . ConsideP Figure , alleviaP Figure , and theP Figure , and theP Figure . OverallP Figure . Our res3.8t‐test was applied. For comparisons of more than two treatment groups, analysis of variance (ANOVA) and Tukey's posthoc test were performed. p < 0.05 was considered to indicate a statistically significant difference .Software SPSS 22.0 and GraphPad Prism 9.0 were used for data analysis, and the data were expressed as the mean ± standard error of the mean (SEM). For pairwise comparisons, an unpaired 4In recent years, the role of C9orf72 in neurodegenerative diseases has received increasing attention, with reports of its expression changes in AD and ALS,We applied the neurotoxic drug MPTP to simulate the environmental factors, α‐synuclein A53T adenovirus injection to simulate genetic factors, and α‐synuclein PFF adenovirus injection to simulate the preclinical factors to induce PD. We recorded behavioral changes in mice in the animal models ; the dopaminergic neurons were lost, and the C9orf72 expression was significantly reduced, accompanied by autophagy dysfunction and the accumulation of autophagy substrates. The corresponding results were confirmed at the cellular level. However, the expression of C9orf72 mRNA did not decrease, indicating that the expression change of C9orf72 in PD was degraded at the protein level.In addition, to further verify the relationship between C9orf72 and autophagy, we constructed sh‐C9orf72 adenovirus to downregulate the expression of C9orf72 protein and evaluated whether the reduction of the C9orf72 protein level could lead to autophagy disorder. The experimental results revealed that the downregulation of C9orf72 protein expression led to autophagy dysfunction, such as the downregulation of LC3II/I expression and the upregulation of p62 and α‐synuclein expression. We also constructed the Flag‐C9orf72 plasmid to construct a model for overexpressing C9orf72 in SH‐SY5Y cells and neurons. The model proved that, after the overexpression of C9orf72, the expression levels of p62 and α‐synuclein were reduced when compared with those in the vector group, thereby demonstrating that the overexpression of C9orf72 activated autophagy and promoted the degradation of autophagy substrates, upregulated the expression of LC3II/I, and downregulated the expression of p62 and α‐synuclein. However, whether the overexpression of C9orf72 led to the same autophagy‐activating effect in animal models warrants further in‐depth studies.Cdk5, a special member of the cyclin‐dependent protein kinase (Cdk) family, is considered a neuron‐specific kinase that plays an important role in several cellular functions, including cell motility and survival. It exerts its biological effects by phosphorylating serine/threonine.Furthermore, we tested whether the decrease in C9orf72 expression could be slowed down by inhibiting the Cdk5 activity with the Cdk5 inhibitor ROSCOVITINE. Our experimental results revealed that, in SH‐SY5Y and primary neuron cell models, the protein expression of C9orf72 in the ROSCOVITINE group was higher than that in the MPP+ group, implying that Cdk5 was indeed involved in the degradation process of C9orf72. However, Cdk5 possessed several substrates in the nervous system and directly inhibited the activity of Cdk5 kinase, which led to other dysfunctions of the body in vivo. To specifically interfere with Cdk5 on the S9 position of the C9orf72 protein, a polypeptide containing the Ser9 site of the C9orf72 protein, amino acids 4‐14, sequence A: LCPPPSPAVAK was designed. In order to improve its ability to penetrate the cell membrane, myristic acid (Myr) was combined at the N‐terminus of the short peptide. The Myr‐C9orf72 4‐14 peptide targeted and competed with endogenous C9orf72 for binding to Cdk5 in the cells, thereby specifically interfering with Cdk5 phosphorylation of the Ser9 site of the C9orf72 protein. Our experimental results indicated that the Myr‐C9orf72 peptide could effectively protect the neurons in the PD model. Myr‐C9orf72 transmembrane peptide attenuates abnormal autophagy, such as the downregulation of LC3II/I expression, upregulation of p62 and α‐synuclein expression, and dopaminergic neuron death and dyskinesia in PD by interfering with Cdk5 phosphorylation of the Ser9 site of C9orf72 protein. Moreover, Myr‐C9orf72 peptide inhibited the effect of decreased C9orf72 expression in an MPTP‐induced mouse PD model.Presently, the progress of pharmacological intervention in PD is limited to symptomatic treatment, which raises the question of whether effective neuroprotective drugs can be developed to treat symptoms along with delaying the disease progression caused by neuronal death. Our study results provide new ideas and directions for elucidating the mechanism and drug treatment of dopaminergic neuron death during the onset of PD, indicating that C9orf72 provides strong evidence supporting the potential of C9orf72 as a PD therapeutic target. Further research can clinically verify the efficacy and safety of the peptide drug Myr‐C9orf72.In summary, our cumulative results demonstrated that, in PD, the expression level of the C9orf72 protein was significantly reduced and that the key nervous system kinase Cdk5 directly phosphorylated the S9 site of the C9orf72 protein. Specifically, interfering with Cdk5 phosphorylation of the S9 site of C9orf72 alleviated the autophagy dysfunction, such as the downregulation of LC3II/I expression and the upregulation of p62 and α‐synuclein expression, which also alleviated the neuronal death and motor dysfunction mediated by C9orf7 protein degradation.All authors participated in the design and execution of the experiments. Xingfeng Xu and Jianguo Yan wrote this article. Data were analyzed by Yan Su, Mao Li, and Qi Wang, who also reviewed the manuscript. Jianguo Yan and Yali Zhou directed the research and revised the article.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article. This work was supported by the Natural Science Foundation of Guangxi Province (No. 2023GXNSFAA026213), the National Natural Science Foundation of China , Innovation Project of Guangxi Graduate Education (No. YCSW2023417), the Scientific Research and Technology Development Program of Guangxi [grant number AD18281009], Thousands of Young and Middle‐aged Backbone Teachers in Guangxi colleges and Universities Training Plan, and Guangxi Medical and health key cultivation discipline construction project.The authors have declared that no competing interest exists.All authors have consented to the submission of the manuscript.Not applicable.Fig. S1.Click here for additional data file.Fig. S2.Click here for additional data file.Fig. S3.Click here for additional data file.Fig. S4.Click here for additional data file.Fig. S5.Click here for additional data file.


In the present study, the oxygen storage capacity (OSC) of CeO2 was enhanced by doping with other rare earth ions . A series of Undoped and RE–doped CeO2 with different doping levels were synthesized using a solvothermal method following a subsequent calcination process, in which just Ce(NO3)3∙6H2O, RE(NO3)3∙nH2O, ethylene glycol and water were used as raw materials. Surprisingly, the Undoped CeO2 was proved to be a porous material with a multilayered special morphology without any additional templates in this work. The lattice parameters of CeO2 were refined by the least–squares method with highly pure NaCl as the internal standard for peak position calibrations, and the solubility limits of RE ions into CeO2 were determined; the amounts of reducible–reoxidizable Cen+ ions were estimated by fitting the Ce 3d core–levels XPS spectra; the non–stoichiometric oxygen vacancy (VO) defects of CeO2 were analyzed qualitatively and quantitatively by O 1s XPS fitting and Raman scattering; and the OSC was quantified by the amount of H2 consumption per gram of CeO2 based on hydrogen temperature programmed reduction (H2–TPR) measurements. The maximum [OSC] of CeO2 appeared at 5 mol.% Yb–, 4 mol.% Y–, 4 mol.% Sm– and 7 mol.% La–doping with the values of 0.444, 0.387, 0.352 and 0.380 mmol H2/g by an increase of 93.04, 68.26, 53.04 and 65.22%. Moreover, the dominant factor for promoting the OSC of RE–doped CeO2 was analyzed.CeO Moreover, CeO2 has the advantages of low toxicity and reusability, so it has attracted great attention in the detection of food biological and chemical substances, catalysis and fuel cell fields 2 synthess of Gd–  doped Ce2 crystal, the Ce 3d XPS regions of Undoped and 4 mol.% RE–doped CeO2 were recorded and fitted, as shown in 2 samples were fitted into eight peaks, corresponding to four pairs of spin–orbit doublets (u1–4 and v1–4) of Ce ions, in which the ui and vi bands corresponded to the contributions of Ce 3d3/2 and Ce 3d5/2. Moreover, the bands of u4, u3 and u1  were attributed to the Ce4+ state, while u2 and v2 were due to the Ce3+ state XPS, could be calculated by the ratio of integrated peak areas of the peak related to the Ce3+ species (u2 and v2 peaks) to that of all peaks (u1–4 and v1–4 peaks) in 3+]XPS values of 4 mol.% Yb, Y, Sm and La–doped CeO2 were 13.78, 12.60, 10.94 and 9.78%, respectively, higher than that of Undoped CeO2 (6.54%), which indicates that Undoped CeO2 itself contained a certain number of Ce3+ ions, and RE–doping could promote the formation of Ce3+ species. In other words, the amount of reducible–reoxidizable Cen+  ions increased with the introduction of RE ions into CeO2 lattice, indicating that RE–doping was conducive to improving the redox capacity of CeO2. In order to understand the effect of RE–doping on Ce ions in the CeO3+ state . Meanwhi2, the O 1s core–level XPS spectra of Undoped and 4 mol.% RE–doped CeO2 were recorded and fitted, as shown in 2 in 2. The peaks with a binding energy of ~529.8 and ~528.4 eV could be assigned to lattice oxygen of O–Ce(IV) species and O–Ce(III) species, respectively, whereas that of ~531.6 eV (yellow region peak) could be assigned to the chemisorption of oxygen or/and weakly bonded oxygen species related to VO defects. For the O 1s spectra of RE–doped CeO2 in VO content could be estimated by the ratio of the integrated area of the peak related to the VO defect . This result indicated that RE–doping was beneficial for the VO creation in CeO2.To investigate the chemical states of O in CeO2 lattice with positive trivalent states, and RE–doping could increase the amount of redox Cen+ (Ce3+/Ce4+) of CeO2, as well as the VO defects.From the results of XPS analyses in VO defect, Raman scattering was employed to investigate the structure of Undoped and RE–doped CeO2 synthesized using the hydrothermal process at 200 °C for 24 h and followed by calcination in air at 500 °C for 2 h  value reached a maximum with a doping level of 5 mol.% and decreased at a higher Yb content. Interestingly, Y–, Sm– and La–doped CeO2 also showed similar trends, reaching the maximum H2 consumptions with doping contents of 4, 4 and 7 mol.%, respectively. The [OSC] values of 5 mol.% Yb–, 4 mol.% Y–, 4 mol.% Sm– and 7 mol.% La–doped CeO2 were 0.444, 0.387, 0.352 and 0.380 mmol H2/g, with an increase of 93.04, 68.26, 53.04 and 65.22% compared with that of the Undoped one (0.230 mmol H2/g). These findings indicate that RE–doping could effectively improve the OSC of CeO2, combined with the H2–TPR curves. This enhanced OSC of RE–doped CeO2 could be explained as follows. When RE3+ ions were doped into the CeO2 lattice to substitute host Ce4+ ions, more VO defects would be generated to keep the electric neutrality of the fluorite structure, and a substoichiometric solid solution Ce1–xRExO2−σ  was formed based on RE–doping. During the H2 reduction of H2–TPR, H2 reacted with a chemisorbed oxygen from the CeO2 surface, which was fixed by intrinsic and extrinsic VO defects on the CeO2 surface. As the surface chemisorbed oxygen was gradually consumed, the intrinsic and extrinsic VO defects were exposed, and the bulk lattice oxygen began to move to the CeO2 surface for replenishment by the VO defects. The oxygen in the bulk RE–doped CeO2 diffused more easily to the surface to fill the VO defects than that in the Undoped CeO2 due to the activation effect of RE3+ dopants which induced oxygen mobility  value of 0.352 mmol H2/g in 2/g in 2 with saturation doping concentration, 5 mol.% Yb–doped CeO2 exhibited the minimum specific surface area of 93.1 m2/g in 2/g. Alternatively, the morphology was also not a major factor influencing the OSC of RE–doped CeO2, which is supported by the similar multilayered morphology in 2, one conclusion could be drawn that the enhanced OSC might be attributed to the incorporation of positive trivalent RE3+ ions into the CeO2 lattice, and partially substituted the host Ce4+ ions, promoting the formation of more VO defects and the oxidation/reduction cycle of Ce3+ ⇔ Ce4+. This result could be supported by the lattice parameter analysis in In order to further demonstrate the porous structure of CeOructures , and thetures  values were 0.444, 0.387, 0.352 and 0.380 mmol/g, much higher than that of the Undoped one (0.230 mmol/g), with an increase of 93.04, 68.26, 53.04 and 65.22%, respectively. The enhanced OSC of RE–doped CeO2 should be attributed to the impurity–induced defects by the substitution of host Ce4+ with RE3+ into CeO2, rather than the effects of its specific surface area and morphology.In summary, a series of RE–substituted CeO


Due to its high water solubility, large hydrophobic cavity and distinct 1H NMR fingerprint {Pd84}Ac is an ideal molecule for exploring supramolecular behaviour with small organic molecules in aqueous media. Molecular visualisation studies highlighted potential binding sites between {Pd84}Ac and these species. Nuclear Magnetic Resonance (NMR) techniques, including 1H NMR, 1H Diffusion Ordered Spectroscopy (DOSY) and Nuclear Overhauser Spectroscopy (NOESY), were employed to study the supramolecular chemistry of this system. Here, we provide conclusive evidence that {Pd84}Ac forms a 1 : 7 host‐guest complex with benzyl viologen (BV2+) in aqueous solution.Polyoxopalladates (POPs) are a class of self‐assembling palladium‐oxide clusters that span a variety of sizes, shapes and compositions. The largest of this family, {Pd 84}Ac) is shown to act as a water‐soluble inorganic host encapsulating organic guests in a Russian Doll fashion. NMR analysis including 1H NMR, Diffusion Ordered Spectroscopy (DOSY) and Nuclear Overhauser Spectroscopy (NOESY), as well as ESI‐MS, was used to study the supramolecular chemistry of this system providing conclusive evidence that {Pd84}Ac forms a 1 : 7 host‐guest complex with benzyl viologen (BV2+) in aqueous solution.The largest anionic polyoxopalladate ({Pd With its hydrophobic cavity, multiple binding sites, high water solubility and charge of −70 this nano‐wheel is an excellent candidate for studying host‐guest chemistry.[N,N′‐dialkyl‐4,4′‐bipyridinium salts) such as benzyl viologen (BV2+) are well‐known for their strong redox, electrochromic and photochromic properties.[84}Ac, by investigating its interaction with benzyl viologen, BV2+  are a class of large, self‐assembling inorganic structures formed by the condensation of metal oxides, usually under acidic conditions.2, 3 F+ Figure , and cha84}Ac has D7d symmetry and is composed of 14 {Pd6} repeating units: {Pd6(μ4‐O)2(μ2‐O)(CH3CO2)2(PO4)3}. In each {Pd6} building block six palladium atoms are linked by μ4‐O oxo ligands, capped by two phosphate ligands which are on the outer surface of the sub‐unit and bridged by a single phosphate group. One acetate ligand points into the centre of the cavity and one sits on the outer surface. The outer ligands point perpendicular to each other and lie on alternating faces of the {Pd6} sub‐units minimising steric hindrance. The arrangement of these ligands on the internal surface of the nano‐wheel creates pockets with an electro‐positive nature. The 1H NMR displays a single set of well‐resolved peaks for the carboxylate ligands on the inner and outer rim of {Pd84}Ac. The inner −CH3 protons, I, are represented by a peak at 2.53 ppm whilst the outer −CH3 protons, II, resonate upfield with a broad peak at 1.86 ppm, Figure S5. Hydrolysis occurs on a slow time‐scale relative to the NMR measurement, therefore an equilibrium exists between charge separated (i.e. free) acetate ligands and those bound to palladium centres and there is correspondingly three distinct resonances in the spectrum for the bound ligands (I and II) and the free ligands.I and II arises from the subtle variance in their respective chemical environments. The internal carboxylate ligand methyl tails are near each other compared to those on the outer face. There is a single μ2‐O connecting two Pd atoms on the inner surface on the nano‐wheel and two phosphate groups capping the sub‐unit on either side. The outer surface of the nano‐wheel has only a single phosphate which bridges each {Pd6}. These dissimilarities make the internal surface slightly more electro‐positive than the external surface corresponding to the slight downfield shift of the inner −CH3 due to the de‐shielding effect caused by this electronic environment.{Pd84}Ac, with its acetate ligands on the inner and outer surface is a richly hydrophobic environment that is filled with water molecules when it exists alone in solution. Enthalpic hydrophobic interactions occur in systems where there is a single organic (often apolar) guest molecule in aqueous solution within a cavity.[84}Ac molecule are in close proximity to one another we predict that the binding event of a single guest would enhance the possibility of further binding through π‐π‐stacking between guest species. This process is known as positive cooperativity and a number of such supramolecular host‐guest systems have been reported using NMR, UV/Vis and calorimetry.[Supramolecular systems rely on a variety of non‐covalent bonds to stabilise the interaction: electrostatic interactions, van der Waals forces, π‐effects and the hydrophobic effect.a cavity.37, 381H NMR titration experiment involving sequential addition of 0.18 mM solution of BV2+ in D2O to a 0.18 mM solution of {Pd84}Ac in D2O shows the formation of a large supramolecular host‐guest complex  in the solid state. ESI‐MS of this precipitate, shown in Figure S10 & Table S12, shows a trend in charge:guest ratio which allows us to suggest that this precipitate represents a {Pd84} : BV stoichiometry of 1 : 8. This implies that after encapsulation of seven guests the 8th equivalent of BV replaces an exo bound cation, initiating precipitation of the complex.The 84}Ac and benzyl viologen. During complexation the chemical environment of BV2+ protons changes, which has consequences on the chemical shift (Δδ) of each proton. In this system the guest experiences an overall de‐shielding effect with Hα, Hβ and Hγ moving downfield whilst Hδ is unchanged. The change in chemical shift was plotted for each guest proton, separately, and is found in Figure 2+ guest species interacting with {Pd84}Ac molecular visualisation was completed using WebLab ViewerLite 3.7, Figure without computational optimisation or energy minimisation. These visualisation models suggest it is possible for seven BV2+ molecules to sit inside the hydrophobic cavity of {Pd84}Ac, each being held in one of the pockets by interaction of the pyridinium protons, Hα Hβ, and the inner ligand of the host, I. The benzyl rings (associated protons denoted Hγ) at either end of the guest flank and wrap around the torus of the nano‐wheel. This is likely aided by the flexible sp3 hybridised methylene, Hδ, which links these rings to the central, rigid and cationic viologen platform.The method of continuous variation was used to evaluate the binding stoichiometry between {Pd1H DOSY NMR is used to provide information about the tumbling rate of molecules in solution. It is a well‐established method in host‐guest chemistry to highlight differences in diffusion rates when guest species are bound to a host molecule compared to that of when it is moving freely.[2+ guest and {Pd84}Ac host tumble at an average rate of 401 pm2 s−1 and 207 pm2 s−1, respectively when they are alone in solution. In a 1 : 7 solution of the two components there is a significant decrease in the average diffusion coefficients for BV2+ to 144 pm2 s−1 and {Pd84}Ac to 113 pm2 s−1. This decrease in rate of tumbling is evidence to show that the BV2+ is interacting with another component which slows its motion through solution. The similarity in diffusion coefficient for both host and guest components when they are together in solution suggests that they are bound together and have formed a supramolecular system. It is interesting to note that there is a slight variation in diffusion coefficient for the protons on BV2+, corroborating nicely with the molecular visualisation data. Hα and Hβ are tightly bound within the internal pockets of the POP, interacting strongly with the methyl groups on internal acetate ligands. These two protons have smaller diffusion values than Hγ and Hδ meaning they are moving slower through solution. The methylene Hδ protons are bonded to a flexible sp3 carbon atom and so their motion is likely to be marginally faster. Benzylic protons, Hγ, sit exposed to the outer environment and therefore experience faster motion, and a larger diffusion coefficient.2D g freely.55, 561H‐1H NOESY NMR is used to determine through‐space interactions occurring between host and guest on complexation. Couplings from host to guest, and guest to host were observed between inner ligand −CH3 of {Pd84}Ac and all four guest resonances; Hα, Hβ and Hγ and Hδ, Figure 2+ resonances and the outer ligand −CH3 group, II. It is clear from the 1H NMR titration data  that guests interact exclusively within the cavity of {Pd84}Ac and not on the outer surface, therefore couplings to outer ligand −CH3 of{Pd84}Ac, II, are not expected.84}Ac@nBV2+, led us to investigate the possibility of further encapsulation by another species within the cavity created by the lining of the organic guest molecules. The development of supramolecular systems which include unfunctionalised C60‐fullerene is of great interest due to the unique properties of the carbon allotrope, but has often been limited to the C60‐fullerene hosting a single atom or small molecule , as opposed to another larger molecule hosting C60‐fullerene.[60‐fullerene are even more sought after due to their potential application in biology, but this brings synthetic challenges.60‐fullerene is 7 Å. Therefore we hypothesise that the C60‐fullerene would sit on the edge of this cavity created by the BV2+ guests as opposed to sitting directly inside the secondary cavity, Figure S22. This is more likely due to the Rebek limit of 55 % which suggests that supramolecular inclusion is only possible when the guest species is ≤55 % of the diameter of the space it is intended to occupy.13C NMR experiments of {Pd84}Ac, BV2+ and C60‐fullerene revealed shifting and broadening associated with supramolecular complexation, Figure 60‐fullerene has a strong and characteristic resonance at 143.6 ppm in toluene‐d8. This solvent was chosen due to the poor solubility of C60‐fullerene in most organic solvents, despite its similar resonance to the aromatic benzyl viologen guest species. A solvent system of 5 : 2 D2O : toluene‐d8 was employed to aid solvation of the C60‐fullerene and because the polyoxopalladate is only soluble in aqueous solution. 1H‐13C HSQC NMR was carried out on seven equivalents of BV2+ in this solvent system to show that the peaks are distinguishable from one another, Figure S14. 13C NMR experiments were carried out on the three‐component system as well as a variety of appropriate controls and all spectra were calibrated in alignment with toluene‐d8 solvent peaks. The inner and outer acetate ligands of {Pd84}Ac have two associated resonances for the carboxylate and methyl components. The inner ligand resonates at 187.4 ppm and 23.3 ppm, respectively, whilst the outer ligand resonates at 185.9 ppm and 22.5 ppm, respectively as shown in Figure S20b. On addition of BV2+ or C60‐fullerene to the polyoxopalladate there is no significant change in these shifts. The benzyl viologen guest species  has eight distinct peaks in the spectrum‐ 150.4 ppm and 145.6 ppm for C1 and C2, 132.4 ppm for C3, 130.3 ppm, 129.8 ppm and 129.4 ppm for C4, C5 and C6, 127.2 ppm for C7 and 65.4 ppm for C8. The benzyl viologen sees a slight change in shift for all resonances when it is in the presence of the polyoxopalladate, Figure 60‐fullerene seen in Figure 60‐fullerene is added to the {Pd84}Ac and BV2+ there is a change in chemical shift for BV2+. C1 is unchanged whilst C2 shifts downfield to 146.4 ppm (Δ 0.8 ppm) and C3 moves downfield to 133.3 ppm (Δ 0.9 ppm). C4, C5 and C6 are the carbon atoms associated with the benzyl rings on the BV2+ guest species, on addition of the C60‐fullerene to the pre‐formed supramolecular complex these resonances significantly broaden and C6 and C7 become slightly lost to the solvent peaks. However, using 1H‐13C HSQC NMR it is possible to distinguish these resonances from one another and to be sure they originate from the guest species rather than the solvent system‐Figure S15, S16 and S17. C8 is significantly shifted to 65.4 ppm (Δ 1.0 ppm). The binding of C60‐fullerene to the secondary cavity is most likely to be on the surface that is created by the benzyl rings of the guest which protrude from the cavity. Therefore, C3 and C8 are anticipated to be the most strongly affected by the addition of the C60‐fullerene, a hypothesis backed by the data.Formation of the supramolecular polyoxopalladate complex, {Pdullerene.59, 601H and 13C NMR chemical shifts as well as 1H NMR DOSY and NOESY data show the location of the interaction, definitively, to be on the internal surface of the nano‐wheel and to be driven by the hydrophobic effect and electrostatic forces between the sub‐units of the anionic polyoxopalladate and the cationic guest. Encapsulation of unfunctionalised C60‐fullerene inside this supramolecular complex was confirmed, similarly, by 13C NMR. This represents an interesting and biologically relevant system for potential application in biomedicine and catalysis.Work on supramolecular systems has focussed on organic macrocycles and their interactions with other molecules in organic solvents. Limitations of these systems include their lack of biological mimicry and the number of guest species that can be incorporated into them. Here we present a system with 7 guest molecules bound into symmetrical pockets of a nanoscale polyoxopalladate which is stable in water. The authors declare no conflict of interest.1As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re‐organized for online delivery, but are not copy‐edited or typeset. 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