Non‐Lignin Constructing the Gas–Solid Interface for Enhancing the Photothermal Catalytic Water Vapor Splitting

Abstract The progress of solar‐driven water‐splitting technology has been impeded by the limited light response capability of semiconductor materials. Despite attempts to leverage nearly 50% of infrared radiation for photothermal synergy and catalytic reaction enhancement, heat loss during liquid phase reactions results in low energy conversion efficiency. Here, the photothermally driven catalytic water‐splitting system, which designs K‐SrTiO₃‐loaded TiN silica wool at the water–air interface. Photocatalytic tests and density functional theory calculations demonstrate that the thermal effect transforms liquid water into water vapor, thereby reducing the reaction free energy of catalysts and improving the transmission rate of catalytic products. Hence, the hydrogen evolution rate reaches 275.46 mmol m⁻² h⁻¹, and the solar‐to‐hydrogen (STH) efficiency is 1.81% under 1 sun irradiation in this gas–solid system, which is more than twice that of liquid water splitting. This novel photothermal catalytic pathway, which involves a coupled reaction of water evaporation and water splitting, is anticipated to broaden the utilization range of the solar spectrum and significantly enhance the conversion efficiency of STH.