Optimizing Electron Configuration of Cobalt‐Based Cocatalysts Supported by Carbon Nitride Nanosheets to Achieve Enhanced Photocatalytic Water Oxidation

Abstract Cobalt‐based materials are promising cocatalysts applied to polymeric carbon nitride (PCN) photocatalysts to achieve water oxidation due to their cost‐effectiveness and comparable activity to Ru and Ir‐based metal oxides. In this study, by optimizing the electron configuration of cobalt‐based materials, a novel oxygen evolution cocatalyst, cobalt disulfide (CoS 2 ), was developed to hybridize with PCN. A series of experimental and theoretical studies reveal that loading CoS 2 on PCN contributes to improving photoinduced charge carrier transportation and reducing activation energy of the oxygen evolution reaction, thus achieving a significantly enhanced photocatalytic performance than the pure PCN. Furthermore, due to the more satisfactory electronic configuration of CoS 2 , the photocatalytic oxygen evolution rate of CoS 2 /CNNS hybrid is even more than 1 time higher than that of Co 3 O 4 /CNNS hybrid.