Constructing g-C3N4 quantum dots modified g-C3N4/GO nanosheet aerogel for UV-Vis-NIR driven highly efficient photocatalytic H2 production

Abstract The development of ultraviolet to near-infrared (UV-Vis-NIR) responsive photocatalysts offers a unique opportunity for the full use of solar energy to solve the energy and the environmental problems. Here, successful preparation of a three-dimensional (3D) porous photocatalyst of graphitic carbon nitride quantum dot (CNQDs) modified g-C3N4/graphene oxide composite aerogel (CNGO/CNQDs) via hydrothermal and vacuum injection method was reported. In this unique ternary 3D photocatalyst, graphene oxide could improve the separation of photogenerated electrons and holes and promote the charge separation, while the aerogel's 3D network structure provided a rich active site. Simultaneously, due to the appropriate up-conversion performance of the nitrogen carbide quantum dots, CNGO/CNQDs achieved a light response from ultraviolet (UV) to near-infrared (NIR). These properties endow it with a good photocatalytic performance. The hydrogen production efficiency of CNGO/CNQDs reached 1231 μmol h−1, which was 16 times more than that of matrix material. In addition, the apparent quantum yields (AQY) of CNGO/CNQDs at wavelengths of 420 nm and 700 nm were 13% and 0.116%, respectively.