Single-atomic Pt sites anchored on defective TiO2 nanosheets as a superior photocatalyst for hydrogen evolution

Single-atomic site catalysts have drawn considerable attention because of their maximum atom-utilization efficiency and excellent catalytic activity. In this work, a highly active single-atomic Pt site photocatalyst was synthesized through employing defective TiO2 nanosheets as solid support for photocatalytic water splitting. It indicated that the surface oxygen vacancies on defective TiO2 nanosheets could effectively stabilize the single-atomic Pt sites through constructing a three-center Ti-Pt-Ti structure. The Ti-Pt-Ti structure can hold the stability of isolated single-atomic Pt sites and facilitate the separation and transfer of photoinduced charge carriers, thereby greatly improving the photocatalytic H-2 evolution. Notably, our synthesized photocatalyst exhibited a remarkably enhanced H-2 evolution performance, and the H-2 production rate is up to 13460.7 mu mol.h(-1).g(-1), which is up to around 29.0 and 4.7 times higher than those of TiO2 nanosheets and Pt nanoparticles-TiO2. In addition, a plausible enhanced reaction mechanism was also proposed combining with photo-electrochemical characterizations and density functional theory (DFT) calculation results. Ultimately, it is believed that this work highlights the benefits of a single-site catalyst and paves the way to rationally design the highly active and stable single-atomic site photocatalysts on metal oxide support. (C) 2021 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

A highly active single-atomic Pt site photocatalyst was synthesized using defective TiO2 nanosheets as solid support, leading to significantly improved photocatalytic H-2 evolution performance. The Ti-Pt-Ti structure effectively stabilized the single-atomic Pt sites and facilitated the separation and transfer of photoinduced charge carriers, highlighting the benefits of a single-site catalyst for rational design of highly active and stable photocatalysts.