Origin of Hysteresis in Perovskite Solar Cells

Abstract

The presence of hysteresis in perovskite solar cells (PSCs) complicates the reliable evaluation of cell performance for practical applications. Numerous efforts have been made to figure out the reasons behind this phenomenon and to resolve the hysteresis, but it still needs to be explored for better understanding. This chapter is mainly focused on theoretical and experimental studies to reveal the origin of the hysteresis and discuss the remedies to eliminate the hysteric behavior in PSCs. In the last few years, the PSC has emerged as one of the fastest growing photovoltaic technologies that achieved high-power conversion efficiency (>25%) in a short span of time. Despite the high efficiency attained, PSCs suffer from current density-voltage (J-V) hysteresis when J-V characteristics were traced in forward and reverse scans. The presence of hysteresis in PSCs significantly influences the photovoltaic (PV) properties and most importantly device stability. Generally, the hysteric behavior in a PSC arises due to ferroelectric polarization, charge carrier trapping/detrapping, and ion migration in the perovskite materials. A systematic discussion on the key factors involved in the hysteresis generation and how it can be eliminated from PSCs, which includes improvement in morphology by either increasing grain sizes, additive doping, interface engineering, device architecture, etc. On the other hand, the hysteresis can also be positively utilized in other applications such as memristive switching devices.