Engineering the Atomic Interface with Single Platinum Atoms for Enhanced Photocatalytic Hydrogen Production

It is highly desirable but challenging to optimize the structure of photocatalysts at the atomic scale to facilitate the separation of electron–hole pairs for enhanced performance. Now, a highly efficient photocatalyst is formed by assembling single Pt atoms on a defective TiO₂ support (Pt₁/def-TiO₂). Apart from being proton reduction sites, single Pt atoms promote the neighboring TiO₂ units to generate surface oxygen vacancies and form a Pt-O-Ti³⁺ atomic interface. Experimental results and density functional theory calculations demonstrate that the Pt-O-Ti³⁺ atomic interface effectively facilitates photogenerated electrons to transfer from Ti³⁺ defective sites to single Pt atoms, thereby enhancing the separation of electron–hole pairs. This unique structure makes Pt₁/def-TiO₂ exhibit a record-level photocatalytic hydrogen production performance with an unexpectedly high turnover frequency of 51423 h⁻¹, exceeding the Pt nanoparticle supported TiO₂ catalyst by a factor of 591.