In situ growing of CoO nanoparticles on g-C₃N₄ composites with highly improved photocatalytic activity for hydrogen...

CoO/g-C₃N₄ hybrid catalyst is facilely prepared for application to photocatalytic H₂ evolution from water splitting by the vacuum rotation-evaporation and in situ thermal method. The physical and chemical properties of CoO/g-C₃N₄ are determined by a series of characterization methods. The g-C₃N₄ with 0.6 wt% Co loading exhibits superior photocatalytic hydrogen evolution activity with an H₂ evolution amount of 23.25 mmol g^-1 after 5 h. The obtained 0.6 wt% CoO/g-C₃N₄ can split water to generate 0.39 mmol g^-1 H₂ without sacrificial agent and noble metal, while the pure g-C₃N₄ is inactive under the same reaction conditions. The remarkable enhancement of photocatalytic H₂ evolution activity of CoO/g-C₃N₄ composites is mainly ascribed to the effective separation of electron-hole pairs and charge transfer. The work creates new opportunities for the design of low-cost g-C₃N₄-based photocatalysts with high photocatalytic H₂ evolution activity from overall water splitting.