Construction of Chemically Bonded Interface of Organic/Inorganic g-C(3)N(4)/LDH Heterojunction for Z-Schematic Photocatalytic H(2) Generation

The design and synthesis of a Z-schematic photocatalytic heterostructure with an intimate interface is of great significance for the migration and separation of photogenerated charge carriers, but still remains a challenge. Here, we developed an efficient Z-scheme organic/inorganic g-C(3)N(4)/LDH heterojunction by in situ growing of inorganic CoAl-LDH firmly on organic g-C(3)N(4) nanosheet (NS). Benefiting from the two-dimensional (2D) morphology and the surface exposed pyridine-like nitrogen atoms, the g-C(3)N(4) NS offers efficient trap sits to capture transition metal ions. As such, CoAl-LDH NS can be tightly attached onto the g-C(3)N(4) NS, forming a strong interaction between CoAl-LDH and g-C(3)N(4) via nitrogen–metal bonds. Moreover, the 2D/2D interface provides a high-speed channel for the interfacial charge transfer. As a result, the prepared heterojunction composite exhibits a greatly improved photocatalytic H(2) evolution activity, as well as considerable stability. Under visible light irradiation of 4 h, the optimal H(2) evolution rate reaches 1952.9 μmol g(−1), which is 8.4 times of the bare g-C(3)N(4) NS. The in situ construction of organic/inorganic heterojunction with a chemical-bonded interface may provide guidance for the designing of high-performance heterostructure photocatalysts.