One‐step decoration of subnanometer MoO x clusters on Bi11VO19 nanotubes for visible‐light‐driven water oxidation

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 Bi11VO19 nanotubes with the coatalyst of subnanometer MoOx clusters (denoted as Bi11VO19/MoOx hetero‐nanotubes) via a one‐step cation‐exchange solvothermal reaction using Na2V6O16 nanowires as the hard template. It is observed that the morphology and microstructure of Bi11VO19/MoOx hetero‐nanotubes vary with the dosage of Mo source and polyvinylpyrrolidone, as well as with the solvent composition. The optimized Bi11VO19/MoOx hetero‐nanotubes significantly enhance the photooxidation of water to oxygen with visible light, delivering an oxygen production rate of 790 mmol g−1 h−1, which is 12 times that of bare Bi11VO19 nanotubes. In situ X–ray photoelectron spectroscopy and (photo)electrochemical characterization suggest that the enhanced photoactivity may be caused by the decorated cocatalyst of MoOx clusters, which extracts electrons from Bi11VO19 nanotubes, leaving an abundance of holes for water photooxidation. This work demonstrates a potential strategy to develop photocatalysts for energy conversion by constructing Bi11VO19‐based nanostructures.