Photocatalytic Hydrogen Production from Cellobiose Using TiO₂@Pt(0.5) Immobilized Photocatalyst

Photocatalytic reforming of biomass-derived carbohydrates is a potentially promising route for sustainable hydrogen production under mild conditions. In this work, we investigated the photocatalytic reforming of cellobiose using TiO₂@Pt-(0.5) immobilized on a glass plate as a catalytic film prepared by a spray coating method. The immobilized catalyst exhibited a H₂ production rate of approximately 14 μmol cm^-2 h^-1 at 40 °C, achieving performance comparable to slurry-based systems while eliminating the need for postreaction separation of the photocatalyst. Hydrogen evolution yields were primarily governed by photon energy, catalyst loading, and substrate concentration, whereas the cumulative hydrogen yield remained similar within the investigated temperature range (40-80 °C), despite differences in the initial reaction profile and catalyst stability observed at 80 °C. The catalyst demonstrated a stable performance under the tested experimental conditions, maintaining constant activity over 10 consecutive reuse cycles with no detectable loss of immobilized mass. Liquid-phase analysis revealed that the detected products were consistent with oxidative cleavage reactions during cellobiose photoreforming, leading to formic acid and formaldehyde as the main detected products. Overall, the results indicate that the immobilized TiO₂@Pt-(0.5) photocatalyst demonstrates potential as an effective proof-of-concept material for biomass photoreforming in an immobilized configuration and warrants further optimization and mechanistic investigation.