Doping with SnBr2 in CsPbBr3 to enhance the efficiency of all-inorganic perovskite solar cells

摘要

The good environmental stability of all-inorganic CsPbBr3 perovskite solar cells is crucial for the commercialization of perovskite solar cells. In this paper, an efficiency improvement from 6.85% to 8.63% is achieved by doping SnBr2 into the CsPbBr3 light absorbing layer in FTO/c-TiO2/m-TiO2/CsPbBr3/carbon perovskite solar cells. By doping with SnBr2, the CsPbBr3 perovskite light absorbing layer is more continuous and nonporous, and the charge transport of the CsPbBr3 layer doped with SnBr2 is accelerated. The SnBr2 incorporation also modifies the band structure of the CsPbBr3 perovskite material so that the valence band energy level shifts from -5.6 eV to -5.46 eV. As a result, the energy level between the carbon electrode and the light absorbing layer is more matched, facilitating the charge transport of holes from the light absorbing layer to the carbon electrode. This work highlights a doping method in CsPbBr3 to enhance the solar cell performance.