Modulation of Self-Assembly Enhances the Catalytic Activity of Iron Porphyrin for CO2 Reduction.
Electrochemical reduction of CO2 in aqueous media is an important reaction to produce value-added carbon products in an environmentally and economically friendly manner. Various molecule-based catalytic systems for the reaction have been reported thus far. The key features of state-of-the-art catalytic systems in this field can be summarized as follows: 1) an iron-porphyrin-based scaffold as a catalytic center, 2) a dinuclear active center for the efficient activation of a CO2 molecule, and 3) a hydrophobic channel for the accumulation of CO2 . This article reports a novel approach to construct a catalytic system for CO2 reduction with the aforementioned three key substructures. The self-assembly of a newly designed iron-porphyrin complex bearing bulky substituents with noncovalent interaction ability forms a highly ordered crystalline solid with adjacent catalytically active sites and hydrophobic pores. The obtained crystalline solid serves as an electrocatalyst for CO2 reduction in aqueous media. Note that a relevant iron-porphyrin complex without bulky substituents cannot form a porous structure with adjacent active sites, and the catalytic performance of the crystals of this relevant iron-porphyrin complex is substantially lower than that of the newly developed catalytic system. The present study provides a novel strategy for constructing porous crystalline solids for small-molecule conversions.
['Tasaki|Masahiro|M|', 'Okabe|Yuki|Y|', 'Iwami|Hikaru|H|', 'Akatsuka|Chiharu|C|', 'Kosugi|Kento|K|', 'Negita|Kohei|K|', 'Kusaka|Sinpei|S|', 'Matsuda|Ryotaro|R|', 'Kondo|Mio|M|0000-0001-9627-2331', 'Masaoka|Shigeyuki|S|0000-0003-2678-2269']
D002245:Carbon Dioxide D002384:Catalysis D007501:Iron D010084:Oxidation-Reduction D011166:Porphyrins
self-assembly iron porphyrin porous crystalline solid CO
2 reduction electrocatalysis