Boosted charge transfer in Pt cluster anchored TiO2 microspheres with rich oxygen vacancies for solar driven H2 production from lignocellulosic biomass

Abstract

Solar driven lignocellulosic biomass-to-H₂ conversion through photocatalysis is an economical and clean approach to generate hydrogen fuel. However, the photocatalytic lignocellulosic biomass-to-H₂ conversion efficiency is still very low owing to the lack of a highly reactive photocatalyst. Herein, we reported the construction of Pt nanocluster chemically anchored porous TiO₂ microspheres with abundant oxygen vacancies as a highly efficient photocatalyst for solar driven lignocellulosic biomass-to-H₂ conversion. The oxygen vacancies on the TiO₂ surface not only boost electron transfer across the Pt–TiO₂ interface, but also benefit the formation of ˙OH which acts as a key intermediate for the oxidation of lignocellulose. The Pt/TiO₂ photocatalysts show high photocatalytic performance with the highest H₂ generation rate of 494 μmol g⁻¹ h⁻¹ and an apparent quantum yield of 3.21% at 380 nm in α-cellulose aqueous solution. Furthermore, photocatalytic H₂ production from lignocellulosic biomass has been successfully achieved, and the H₂ generation rate of the optimal Pt/TiO₂ photocatalyst in rice straw, wheat straw, polar wood chip, bamboo, rice hull and corncob aqueous solution was 2, 3, 23, 32, 11 and 6 μmol g⁻¹ h⁻¹, respectively. This study provides an opportunity for encouraging more research on solar driven lignocellulosic biomass-to-H₂ conversion.