Relationship between perovsktie solar cell efficiency and lattice disordering

Multi-cations lead perovskite solar cells have shown higher performance than single-cation perovskite solar cells. This compositional engineering of perovskite material retains the optimum tolerance factor while allowing the tuning of the band gap in addition to the enhanced stability of cubic phase perovskite. However, no in-depth explanation has been provided on the relationship between crystal structure of the perovskite and the solar cell efficiency. In this report, we investigate the effect of lattice disordering of FA_xMA₁−_xPbI₃ perovskite on the tolerance factor and solar cell efficiency. The lattice disordering estimated using Williamson-Hall plot of XRD analysis revealed that the disordering is lowest when x = 0.2 and highest when x = 1.0. Correspondingly, x = 0.2 showed the highest solar cell performance and long carrier lifetime Our results show that the disordering in α phase of FA_xMA₁−_xPbI₃ layer causes lattice deformation which affects the carrier lifetime and solar cell efficiency, instead of the defects on constituent elements.