Strengthening reactive metal-support interaction to stabilize Ni species on the nitrogen vacancies of g-C3N4 for boosting photocatalytic H-2 production

A noble-metal-free Ni species-modified graphitic carbon nitride (CN) photocatalyst (DCN-Ni) is fabricated by stabilizing Ni species on the nitrogen vacancies of g-C3N4. The experimental observation expresses that the nitrogen vacancies in g-C3N4 arouse an obvious electron-deficient effect, which significantly promotes the metal-support interaction by interface bonding states. This strong metal-support interaction builds a conducive highway (Ni-C bonding states) for electrons to transfer from DCN to the Ni species, which contributes to the high separation and transportation efficiency of charge carriers. As a result, the outstanding H-2-evolution activity over DCN-Ni-2 reaches up to about 1.75 times higher than that of Pt/g-C3N4 under visible light. The structure characteristic reveals that the strong metal-support interaction not only stabilizes the Ni species on the electron-deficient g-C(3)N(4)via interface bonding states, but also allows the Ni species to optimize the electronic structures of g-C3N4 for a highly efficient photocatalytic H-2 evolution reaction. This work supplies a reliable guideline for designing and constructing a low-cost, highly efficient, and durable cocatalyst acting on g-C3N4, opening a new channel and possibility for energy and environment-related applications.