Current-voltage hysteresis reduction of CH3NH3PbI3 planar perovskite solar cell by multi-layer absorber

Abstract

In this paper, we present two structures with two and three-layer absorber to reduce the current density-voltage (J-V) characteristics hysteresis of the planar perovskite solar cell. The quantity of hysteresis has significantly decreased by adjusting precursor ratios and thickness of devices layers. The main factor of hysteresis in perovskite solar cells is built-in field screening resulting from ion migration and minority carriers' recombination. In the proposed structures, the reduction of minority carriers decreases recombination in the forward scan. The thickness of the absorber layer of a primary (single-layer) solar cell is 450 nm as the same as the proposed structures in which aggregate thickness is 450 nm. In the single-layer absorber structure, the least quantity of the hysteresis was obtained by 0.0508 with the most precursor quantity. The optimization of thickness and precursor ratio demonstrated the reduction of hysteresis by ∼64% in two-layer absorber structures and ∼88.3% in three-layer absorber structures compared to the single-layer structure.