Hysteresis of I-V Performance: Its Origin and Engineering for Elimination

Although perovskite solar cell exhibits power conversion efficiency as high as 25.5%, the occurrence of anomalous hysteresis in current density (J) -voltage (V) performance has been issued because the hysteresis can have negative effects on not only efficiency but also stability. Therefore, it is important to find solutions to solve the hysteric problem based on better understanding of its origin. In this chapter, we explore the factors affecting J -V hysteresis, in which ion migration is one of possible origins for the hysteresis, possibly seen from in situ photoluminescence image. Furthermore, methods to mitigate J -V hysteresis are described, where potassium ion doping is emphasized as universal approach for diminishing the hysteresis.