Plasma-Tuned nitrogen vacancy graphitic carbon nitride sphere for efficient photocatalytic H2O2 production

The nitrogen vacancy graphitic carbon nitride sphere (NVCNS) synthesized by H2 plasma treatment has showed remarkable enhancement in photocatalytic H2O2 production. The enhancement is attributed to the introduction of N defect state, which is beneficial to adsorption O2 due to the accumulation of electrons on nitrogen vacancies (NV). The NV creates abundant unsaturated sites and induces strong interlayer interactions, leading to effective electronic excitation and promotion of charge transport. [Display omitted] Graphitic carbon nitride (CN) is a promising photocatalyst for sustainable energy conversion. Meanwhile, N vacancies are useful for H2O2 generation; however, they are hard to control. In this study, the N vacancy CN sphere (NVCNS) is synthesized by H2 plasma treatment to tune the NV. The as-synthesized NVCNS exhibits an efficient and stable photocatalytic H2O2 yield of 4413.1 μmol gcat−1h−1, which is 2.5 and 4.6 times higher than that of CNS (1766.4 μmol gcat−1h−1) and bulk CN (956.6 μmol gcat−1h−1), respectively, using a Xe lamp with an intensity of 100 mWcm−2. In particular, the charges recombination rate is remarkably reduced by introducing N defect state, promoting electron accumulation and O2 adsorption, through theoretical calculation and experiments. Furthermore, the NV creates abundant unsaturated sites and induces strong interlayer interactions, leading to effective electronic excitation and the promotion of charge transport.