Heterostructure with tightly-bound interface between In2O3 hollow fiber and ZnIn2S4 nanosheet toward efficient visible light driven hydrogen evolution

Visible-light-driven photocatalytic hydrogen evolution is considered as one of the most useful approaches to produce renewable fuels from abundant resources. Indium oxide (In2O3) has attracted much attention in the field of solar hydrogen production due to its moderate band gap, which can be driven by visible light easily. However, the efficiency of hydrogen evolution reaction (HER) of In2O3 is currently unsatisfactory. To enhance the HER efficiency of In2O3, herein, sandwich-structured In2O3/ZnIn2S4 heterostructure was precisely constructed via in-situ growth of ZnIn2S4 nanosheets on the In2O3 hollow fibers. The fabricated In2O3/ZnIn2S4 heterostructure exhibited a significantly enhanced photocatalytic HER activity of 2.18 mmol/g/h as compared to pure In2O3 and ZnIn2S4. Such efficient photocatalytic hydrogen production is attributed to the tightly-bound interface between (001) planes of flake ZnIn2S4 and (222) planes of In2O3. Experimental and theoretical investigation indicates compactly interface enabling efficient charge transfer and separation, which benefited the excellent photocatalytic HER performance.