Key Words:oxygen vacanciesco-catalystsurface hydroxylphotocatalytichydrogen evolution reaction (HER)

Abstract:Semiconductors-based heterogeneous photocatalytic water splitting has been extensively studied, but it still remains challenging to accelerate the separation of electron-hole pairs and facilitate the reaction kinetics. Here we report a general strategy to fabricate highly efficient Pt/TiO2 photocatalyst by coupling the Pt co-catalysts and surface oxygen vacancies (V-O) of TiO2. TiO2 was pre-modified with alkali or alkaline earth metals ion solutions, which produce a large number of surface hydroxyl on TiO2. Subsequently, the photodeposited Pt sub-nanoparticles substitute surface hydroxyl and induce surface V-O on TiO2. The coupling of Pt and surface V-O on TiO2 can accelerate the extraction of photo-charges through the interaction of Pt-V-O-Ti bonds and reduce the hydrogen evolution barrier, thereby promoting the photocatalytic activity. The synthesized Pt-V-O-TiO2 sample exhibits a photocatalytic hydrogen evolution activity as high as 1.5 L.g(-1).h(-1), which is 2.2 times that of traditional Pt/TiO2. Our findings in-depth understand the synergistic effect of co-catalysts and defects on photocatalysis and open up new possibilities for achieving robust photocatalytic water splitting.

Volume:16

Issue:4

Translation or Not:no