摘要

A novel structure of hexagonal CuSbS2 nanobricks were successfully synthesized on the TiO2 nanorod arrays via a solvothermal method by using polyethylene glycol (PEG) as the morphology-directing agent. The photoelectrochemical properties of TiO2/CuSbS2 films were also characterized and discussed. The results revealed that the PEG could be absorbed on the surface of CuSbS2 nuclei selectively and confine their growth in certain direction. The hexagonal CuSbS2 nanobricks with the side length of 70 nm and thickness of 30 nm were synthesized from a precursor solution containing Cu+, Sb3+, S2- and PEG with an optimal Cu:Sb:S:PEG volume ratio of 2:2:4:1. The CuSbS2 films on the TiO2 nanorod arrays improved the optical absorption and energy conversion efficiency of the bare TiO2 nanorods significantly. The enhanced photoelectrochemical performance of TiO2/CuSbS2 photoelectrodes was attributed to the enlargement of photoresponse range, increasement of the charge carrier density and the fast separation of photogenerated electron-hole pairs. The results of present work demonstrate further insight for improving the efficiency of semiconductors by using a suitable electron transfer channels, which may be promising for rational construction of solar conversion and storage devices.