Mesoporous Crystalline Niobium Oxide with a High Surface Area: A Solid Acid Catalyst for Alkyne Hydration.
A mesoporous crystalline niobium oxide with tunable pore sizes was synthesized via the sol-gel-based inverse micelle method. The material shows a surface area of 127 m2/g, which is the highest surface area reported so far for crystalline niobium oxide synthesized by soft template methods. The material also has a monomodal pore size distribution with an average pore diameter of 5.6 nm. A comprehensive characterization of niobium oxide was performed using powder X-ray diffraction, Brunauer-Emmett-Teller, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, UV-vis, and X-ray photoelectron spectroscopy. The material acts as an environmentally friendly, solid acid catalyst toward hydration of alkynes under with excellent catalytic activity (99% conversion, 99% selectivity, and 4.39 h-1 TOF). Brønsted acid sites present in the catalyst were found to be responsible for the high catalytic activity. The catalyst was reusable up to five cycles without a significant loss of the activity.
['Rathnayake|Dinithi|D|', 'Perera|Inosh|I|', 'Shirazi-Amin|Alireza|A|', 'Kerns|Peter|P|', 'Dissanayake|Shanka|S|', 'Suib|Steven L|SL|http://orcid.org/0000-0003-3073-311X']
mesoporous crystalline niobium oxide solid acids alkyne hydration heterogeneous catalysis