Thermo‐Photocatalytic Methanol Steam Reforming over Low‐Crystalline Au‐Loaded TiO ₂ for Efficient Hydrogen Production

Methanol shows great potential as a liquid hydrogen carrier, and its steam reforming offers a promising route for on‐site hydrogen (H 2 ) production. However, this process typically requires high temperatures. In this study, we developed a thermo‐photocatalytic (TPC) system based on Au‐modified TiO 2 photocatalysts designed to enable methanol steam reforming (MSR) at low temperatures without sacrificing efficiency. The photocatalysts were evaluated for MSR activity under ultraviolet (UV) irradiation (365 nm) across a range of temperatures. Compared with TiO 2 brookite and TiO 2 P25, the low‐crystalline 1.0 wt% Au/TiO 2 anatase catalyst exhibited exceptional TPC performance for MSR despite its low crystallinity. It achieved a hydrogen production rate of 370 mmol g −1 h −1 W −1 at 150°C, with a high apparent quantum efficiency (AQE) of 26.9%. Moreover, complete MSR was achieved with CO‐free hydrogen production. The superior TPC performance of the low‐crystalline TiO 2 is primarily attributed to its higher surface area, stronger electronic interaction with Au, and lower apparent activation energy. Unlike conventional photocatalysis, a linear relationship between light intensity and hydrogen production rate was observed for the TPC process, indicating that energetic electrons were responsible for the TPC reaction. The interplay between thermal and photochemical processes enhances the overall TPC efficiency, thereby improving the MSR performance.