In-situ prepare graphene/g-C3N4 D-π-A in-plane heterojunctions for high-performance photocatalytic hydrogen production

In this study, graphene/g-C3N4 in-plane heterojunctions (SGCN-x) with D-π-A structure are prepared by hydrothermal and pyrolysis carbonization methods. The interfacial bonded hydrothermal precursor can assist the synthesis of graphite carbon and g-C3N4 at mild thermodynamic conditions. The characterizations indicated that graphene was stitched onto the edge of carbon nitride. The interface of the in-plane heterojunction is carbon-nitrogen heterocyclic rings with π conjugate property, which can be regarded as the transmission channel of electrons. That is, the separation/transport of photocarriers in SGCN-x heterostructure is accelerated, and the recombination time of photogenerated electrons and holes is prolonged. The highest yield of hydrogen production performance has reached up to 7446 μmol/(g·h) for the optimization of the photocatalyst, almost 6.73 times higher compared with pure g-C3N4. This work opens new opportunities for the significant strategy for the in-situ preparation of graphene-based materials and construction of efficient photoactive material for catalysis.