Accelerated constant current stress on triple cation perovskite solar cells

Abstract

The increasing demand for renewable and cost-effective energy sources requires not only the development of alternative solar technologies, but these new technologies must be stable enough to be used in a real-life application. For this reason, perovskite solar cells (PSCs) must be investigated not only in terms of power conversion efficiency, but also in terms of reliability. In this work, accelerated forward current stress is applied as a tool to investigate PSCs stability and degradation kinetic emulating real-life scenarios. The choice of the hole-blocking layer (HBL) plays a crucial role in PSCs intrinsic instability as well as in their degradation rate, which follows a stretched exponential law. Here, tin oxide (SnOX) and bathocuproine (BCP) are investigated as HBLs observing that for low stress currents BCP-based PSCs degrade faster than SnOX-based PSCs, whereas for large stress currents SnOX-based PSCs degrade faster than BCP-based PSCs. The results also indicated that the major cause of degradation in the devices is primarily driven by the formation of shunt paths leading to cell breakdown. Our findings offer valuable insights for improving the stability of PSCs under accelerated stress conditions and provide useful information for the design of PSC-based solar panels depending on their field of applications.