One-step synthesis N, O co-doped ZnIn2S4 for efficient photocatalytic H2 production and Cr(VI) reduction

Element doping is generally employed to modify photocatalysts by optimizing their electronic structure, and light absorption, as well as improving charge separation and transfer, which are key factors in photocatalysis. In this study, a simple one-step solvothermal route was employed to synthesize N, O co-doped ZnIn2S4. Systematical analyses demonstrate that the introduction of N and O co-doping leads to enhanced light absorption, increased specific surface areas, and improved charge separation and transfer in comparison to the unmodified ZnIn2S4. As expected, compared with bare ZnIn2S4, the as-prepared N, O co-doped ZnIn2S4 exhibits superior photocatalytic H2 evolution and Cr(VI) photoreduction performance. The H2 evolution rate of the N, O co-doped ZnIn2S4 reaches 2254.0 μmol g-1 h-1, which is 2.8 times of pristine ZnIn2S4. Moreover, the Cr(VI) photoreduction efficiency reaches 99.5% within 50 minutes, and the apparent kinetic constant is nearly 4 times the bare ZnIn2S4. This work contributes to the modification of ZnIn2S4 for photocatalytic H2 generation and Cr(VI) reduction.