Remarkable Enhancement in Solar Oxygen Evolution from MoSe2/Ag3PO4 Heterojunction Photocatalyst via In Situ Constructing Interfacial Contact

Exploring low-cost and earth-abundant cocatalysts is important for developing an efficient photocatalytic system for water splitting. Herein, we report a hybrid photocatalyst consisting of Ag-3 PO4 nanoparticles in situ grown on the surface of two-dimensional MoSe2 nanoarchitectures acting as a noble-metal-free cocatalyst for photocatalytic oxygen evolution under LED-light irradiation. The MoSe2/Ag3PO4 heterojunctions exhibited an obviously enhanced activity for photocatalytic O-2 generation compared with pure Ag3PO4 or the physical mixed samples with the same component, and the MoSe2/Ag3PO4 composite with an optimal ratio of cocatalysts demonstrated the highest O-2 evolution rate of 182 mu mol.L-1.g(-1).h(-1). The highly photocatalytic performance could be mainly ascribed to the formation of close and large contact interface between MoSe2 and Ag3PO4 via in situ preparation method, leading to ultrafast interfacial charge migration and highly efficient charge separation. More importantly, introduction of MoSe2 cocatalyst not only could promote light harvesting and provide more active adsorption sites, but also prevent the photocorrosion of the Ag3PO4 during the photocatalytic reaction. This work may open up new insights for the introduction of a noble-metal-free MoSe2 as an effective cocatalyst for solar energy conversion to achieve O-2 generation.