Solar driven conversion of agricultural biomass to H2 over few-layer MoS2 modified ultra-small TiO2 nanoparticle photocatalysts

Abstract

Agricultural biomass is a kind of abundant renewable resource in nature, and the effective conversion of agricultural biomass to chemical fuel is crucial for reducing dependence on fossil fuels, but it has been limited by the absence of appropriate conversion strategies. Here, we report a simple photocatalytic system for rapid conversion of agricultural biomass to H₂ by using few-layer MoS₂ modified ultra-small TiO₂ nanoparticles (MoS₂@TiO₂ NPs) as photocatalysts. In the α-cellulose system, the H₂ generation rate of the optimized photocatalyst reaches 1653 μmol g⁻¹ h⁻¹ under 300 W Xe lamp irradiation, and the apparent quantum yield at 380 nm reaches 5.62%. Meanwhile, comparable photocatalytic H₂ generation activity was achieved from different agricultural biomass sources of rice straw, corn straw, wheat straw, rice husk, soybean straw and corncob, with a maximum H₂ generation rate of 50 μmol g⁻¹ h⁻¹ in the corncob system. The high photocatalytic H₂ production activity of the MoS₂@TiO₂ NP photocatalyst was attributed to the large specific surface area of TiO₂ NPs and abundant active sites of MoS₂, which respectively promote biomass oxidation and the H₂ generation reaction. This study provides a green approach for agricultural biomass upgrading through a photocatalytic strategy.