Enhancing photocatalytic H(2)O(2) production with S-type heterojunctions of CeO(2) coupled N-vacancy-rich carbon nitride.

Artificial photosynthesis for HO production through O reduction is a sustainable and cost-effective technology for the scientific and industrial communities. Metal-free polymeric carbon nitride (CN) is a promising visible-light responsive semiconductive material for photocatalytic HO production. However, its inherently disordered and amorphous structure limits its performance improvement due to high photogenerated carrier complexation and sluggish interlayer charge transfer. Here, we report a high-performance S-type heterojunction, composed of CeO coupled with N-vacancy-rich CN (CeO/Nv-CN), that enhances the photocatalysis of HO production under visible light. The prepared CeO/Nv-CN showed an HO generation rate of up to 69.79 mmol·g·h, 48.80-fold higher than CN and had an apparent quantum yield of 13.8 % at 400 nm. A synergistic effect among CeO, N-vacancies (Nv) and S-type heterojunction is responsible for such an excellent activity, which increased the O and light absorption sites, built rapid charge diffusion channels, and enhanced two-electron O reduction. This work demonstrates the potential of incorporating nanosized CeO with CN to achieve high-performance photocatalytic HO production, opening new avenues for designing highly efficient polymeric composite photocatalysts for energy conservation.