Performance enhancement of perovskite solar cells by employing TiO2 nanorod arrays decorated with CuInS2 quantum dots.

Abstract In this work, TiO 2 nanorod arrays (TiO 2 -NAs) were modified by CuInS 2 quantum dots (CuInS 2 QDs) on the surface of the nanorods. The resultant TiO 2 -CuInS 2 nanorod arrays (TiO 2 -CuInS 2 -NAs) were characterized by UV/Vis spectroscopy, transmission electronic microscopy (TEM), and X-ray diffraction (XRD). The TiO 2 -CuInS 2 -NAs were applied as scaffold for the preparation of organic-inorganic hybrid perovskite solar cells. In comparison with the solar cell devices based on TIO 2 -NAs, a significant improvement in the power conversion efficiency had been achieved and the highest efficiency was obtained as 11.7% (under 100 mW/cm 2 ) through the optimization of the growth time of QDs on nanorods. The improvement of the device performance could be attributed to the assistance of CuInS 2 QDs in the light harvesting as well as the facilitation of the electron injection from the perovskite to the TiO 2 scaffold.