Regulating Carbon Vacancies and Undercoordinated Mo Sites in Mo2C Catalysts Toward Photo-Thermal Catalytic Conversion of Biomass Into H2 Fuel

Abstract

The conversion of biomass into chemical fuels is exciting but quite challenging in the development of an effective conversion strategy to generate easily-separated products without energy consumption. Herein, a lignocellulosic biomass-to-H₂ conversion system via photo-thermal catalysis over Mo₂C hierarchical nanotube catalysts in an acidic solution, in which the lignocellulose is hydrolyzed to small organic molecules (such as glucose, etc) by dilute H₂SO₄, and then the resulting glucose is oxidized by Mo₂C catalyst to generate H₂ are reported. During the photo-thermal catalytic processes, the carbon vacancy in Mo₂C catalysts results in the generation of undercoordinated Mo sites, which act as active sites for both biomass oxidation and H₂ generation reactions. Thus, the successful photo-thermal catalytic conversion of common agricultural and forestry biomass including polar wood chip, bamboo, wheat straw, rice straw, corncob, and rice hull into H₂ fuel is realized, and the highest H₂ generation rate achieves 30 µmol g⁻¹ h⁻¹ in the wheat straw system. Outwork affords efficient noble-metal-free catalysts with adjustable active sites for photo-thermal catalytic conversion of lignocellulosic biomass into H₂.