Photoelectrochemical behavior of TiO2 nanorod arrays decorated with CuInS2 quantum dots

One-dimensional single crystalline TiO2 nanorod arrays with different lengths were prepared by controlling the hydrothermal cycles, which were successfully sensitized with CuInS2 quantum dots by assembly linking cycles, and their optical absorption properties and photoelectrochemical properties were investigated. 6 μm-TiO2 nanorod electrodes with the CuInS2 quantum dots sensitization of three linking cycles had the best photoelectrochemical properties and short-circuit current density, such as the short-circuit current density are 27.3 times higher than that of pure 6 μm-TiO2 nanorod electrodes. The reason may be attributed to the suitable internal surface area of TiO2 nanorod, with the increasing of the adsorption content of CuInS2 quantum dots to generate much more photo-induce electrons. Moreover, it will also enhance the interface connection between TiO2 nanorod and FTO conducting substrate, which favors to reduce the recombination of photo-induced electron–hole pairs.