Photocatalytic reforming of biomass: A systematic study of hydrogen evolution from glucose solution

The present work reports the renewable hydrogen production by an anaerobic photocatalytic reforming of glucose, a compound that could be derived from biomass, over noble-metal-loaded TiO2 photocatalyst. The effects of reaction parameters, such as reaction atmosphere, noble-metal loading, amount of loaded platinum, crystalline phase of TiO2, initial concentration of glucose, and the pH value of the reaction solution on the hydrogen evolution are systematically investigated. The results show that the photocatalytic H2 production from the glucose solution can be significantly enhanced by depositing various noble metals on anatase TiO2, and the hydrogen evolution rates are decreased in the order Pd > Pt > Au ≈ Rh > Ag ≈ Ru. For Pt/TiO2 the greatest photocatalytic reforming activity of glucose occurs as the Pt loading content of ca. 1.0 wt.%. The presence of O2 and acid strongly inhibits the hydrogen production. The effect of initial concentration of glucose on the hydrogen evolution rate could be well represented by the Langmuir–Hinshelwood kinetics model. A probable mechanism for the photocatalytic reforming process was proposed and discussed.