One‐Step Decoration of Subnanometer MoOx Clusters on Bi11VO19 Nanotubes for Visible‐Light‐Driven Water Oxidation

Abstract For the sluggish reaction kinetics due to a four‐electron transfer process, water oxidation is always a major obstacle to solar splitting of water to hydrogen. It remains a tough challenge to develop efficient nonnoble‐metal photocatalysts for water oxidation. Herein, we decorate the host photocatalyst of Bi 11 VO 19 nanotubes with the coatalyst of subnanometer MoO x clusters (denoted as Bi 11 VO 19 /MoO x hetero‐nanotubes) via a one‐step cation‐exchange solvothermal reaction using Na 2 V 6 O 16 nanowires as the hard template. It is observed that the morphology and microstructure of Bi 11 VO 19 /MoO x hetero‐nanotubes vary with the dosage of Mo source and polyvinylpyrrolidone, as well as with the solvent composition. The optimized Bi 11 VO 19 /MoO x hetero‐nanotubes significantly enhance the photooxidation of water to oxygen with visible light, delivering an oxygen production rate of 790 μmol g −1 h −1 , which is 12 times that of bare Bi 11 VO 19 nanotubes. In situ X‐ray photoelectron spectroscopy and (photo)electrochemical characterization suggest that the enhanced photoactivity may be caused by the decorated cocatalyst of MoO x clusters, which extracts electrons from Bi 11 VO 19 nanotubes, leaving an abundance of holes for water photooxidation. This work demonstrates a potential strategy to develop photocatalysts for energy conversion by constructing Bi 11 VO 19 ‐based nanostructures.