MoSe2-NiSe dual co-catalysts modified g-C3N4 for enhanced photocatalytic H2 generation

Solar energy conversion into hydrogen (H 2 ) energy has attracted much attention. However, the low light utilization rate and fast carrier recombination of photocatalysts extremely limit the practical application of photocatalytic H 2 production. In this paper, MoSe 2 -NiSe with abundant active sites and interfacial electronic structures as dual co-catalysts were assembled on g-C 3 N 4 nanosheets (NSs) vis a solvothermal reaction process. MoSe 2 -NiSe/g-C 3 N 4 NSs composite exhibited improved light absorption and photoelectrochemical properties. The photocatalytic H 2 production rate of MoSe 2 -NiSe/g-C 3 N 4 composite achieved 2379.04 μmol·h −1 ·g −1 , which is 99.25, 1.44, and 3.67 times those of pure g-C 3 N 4 nanosheets (23.97 μmol·h −1 ·g −1 ), MoSe 2 /C 3 N 4 (1654.57 μmol·h −1 ·g −1 ), and NiSe/C 3 N 4 (649.08 μmol·h −1 ·g −1 ), respectively. The apparent quantum efficiency (AQE) value of MoSe 2 -NiSe/g-C 3 N 4 achieved 4.07 % under light at λ = 370 nm. The corresponding characterization and experiments proved that 2D ultrathin g-C 3 N 4 NSs with a large surface area and short charge-transfer distance could facilitate light scattering and the transport of photoexcited electrons. MoSe 2 -NiSe, as a dual co-catalyst, showed strong electronic synergistic interaction between the interfaces, thus improving the conductivity and promoting the electron transfer process.