Dye-Sensitized Cu2XSnS4 (X=Zn, Ni, Fe, Co, and Mn) Nanofibers for Efficient Photocatalytic Hydrogen Evolution

The photocatalytic hydrogen evolution activities of low-cost and noble-metal-free Cu2XSnS4 (X=Zn, Ni, Fe, Co, and Mn) nanofiber catalysts have been investigated using triethanolamine as an electron donor and eosinY as a photosensitizer under visible-light irradiation. The rates of hydrogen evolution by Cu2XSnS4 (X=Zn, Ni, Fe, Co, and Mn) nanofibers have been compared with each other and with that of the noble metal Pt. The hydrogen evolution rates for the nanofibers change in the order Cu2NiSnS4>Cu2FeSnS4>Cu2CoSnS4>Cu2ZnSnS4>Cu2MnSnS4 (2028, 1870, 1926, 1420, and 389molg(-1)h(-1), respectively). The differences between the hydrogen evolution rates of the nanofibers could be attributed to their energy levels. Moreover, Cu2NiSnS4, Cu2FeSnS4, and Cu2CoSnS4 nanofibers show higher and more stable photocatalytic hydrogen production rates than that of the noble metal Pt under long-term irradiation with visible light.