Enhanced Performance of Perovskite CH3NH3PbI3 Solar Cell by Using CH3NH3I as Additive in Sequential Deposition
2015
Xie, Yian | Shao, Feng | Wang, Yaoming | Xu, Tao | Wang, Deliang | Huang, Fuqiang
Sequential deposition is a widely adopted method to prepare CH₃NH₃PbI₃ on mesostructured TiO₂ electrode for organic lead halide perovskite solar cells. However, this method often suffers from the uncontrollable crystal size, surface morphology, and residual PbI₂ in the resulting CH₃NH₃PbI₃, which are all detrimental to the device performance. We herein present an optimized sequential solution deposition method by introducing different amount of CH₃NH₃I in PbI₂ precursor solution in the first step to prepare CH₃NH₃PbI₃ absorber on mesoporous TiO₂ substrates. The addition of CH₃NH₃I in PbI₂ precursor solution can affect the crystallization and composition of PbI₂ raw films, resulting in the variation of UV–vis absorption and surface morphology. Proper addition of CH₃NH₃I not only enhances the absorption but also improves the efficiency of CH₃NH₃PbI₃ solar cells from 11.13% to 13.37%. Photoluminescence spectra suggest that the improvement of device performance is attributed to the decrease of recombination rate of carriers in CH₃NH₃PbI₃ absorber. This current method provides a highly repeatable route for enhancing the efficiency of CH₃NH₃PbI₃ solar cell in the sequential solution deposition method.
显示更多 [+] 显示较少 [-]