Efficient Holes Abstraction by Precisely Decorating Ruthenium Single Atoms and RuOx Clusters on ZnIn2S4 for Photocatalytic Pure Water Splitting

Abstract Developing efficient photocatalysts for two‐electron water splitting with simultaneous H 2 O 2 and H 2 generation shows great promise for practical application. Currently, the efficiency of two‐electron water splitting is still restricted by the low utilization of photogenerated charges, especially holes, of which the transfer rate is much slower than that of electrons. Herein, Ru single atoms and RuO x clusters are co‐decorated on ZnIn 2 S 4 (RuO x /Ru‐ZIS) to employ as multifunctional sites for efficient photocatalytic pure water splitting. Doping of Ru single atoms in the ZIS basal plane enhances holes abstraction from bulk ZIS by regulating the electronic structure, and RuO x clusters offer a strong interfacial electric field to remarkably promote the out‐of‐plane migration of holes from ZIS. Moreover, Ru single atoms and RuO x clusters also serve as active sites for boosting surface water oxidation. As a result, an excellent H 2 and H 2 O 2 evolution rates of 581.9 µmol g −1 h −1 and 464.4 µmol g −1 h −1 is achieved over RuO x /Ru‐ZIS under visible light irradiation, respectively, with an apparent quantum efficiency (AQE) of 4.36% at 400 nm. This work paves a new way to increase charge utilization by manipulating photocatalyst using single atom and clusters.