Layer by Layer Characterization of the Failure Origin Process in Perovskite Solar Cells

Environmental stability of perovskite solar cells (PSCs) has been studied through several testing protocols, including those outlined by the International Electrotechnical Commission (IEC) and the International Summit on Organic Photovoltaics and Solar Cells (ISOS). These standards focus on complete stack-level testing (i.e., complete solar cells and modules). However, in practice, PSCs are likely to undergo degradation in ways that affect each layer of the framework differently, not just the entire cell assembly. The interactions between absorbers, capping layers, passivation, electrodes, and other materials used in solar cells are not fully captured, which might oversimplify the multifactorial degradation process inherent in PSCs in cell-level testing. In this study, a layer-by-layer degradation study protocol is proposed to systematically evaluate the failure mechanisms of individual layers within perovskite solar cells. Using a modular approach, the NiOx/SAM/PK layers are subjected to aging under illumination at ambient temperature and in an inert atmosphere, followed by their reintegration into the full device architecture (e.g., …/C60/SnO2/ITO/Au). Comprehensive compositional-morphological characterization and optoelectrical property measurements of the completed cells are then performed to evaluate the influence of each layer's degradation on the performance and stability of the overall architecture.