Comparison of encapsulation methods for perovskite solar cells via analysis of a large dataset

The lifetime of halide perovskite solar cells (PSCs) is thought to be limited by a combination of intrinsic instability of the PSC materials and extrinsic degradation caused by external aging stressors. PSC encapsulation has proven to be an effective method for improving environmental stability by preventing access to ambient species including oxygen and moisture. The choice of the best PSC encapsulation method in terms of its effect on PSC lifetime requires a thorough comparison of methods. Herein we aim to use meta-analysis of a large database for such a comparison. We developed a methodology for meta-analysis of PSC stability with different encapsulation strategies using data available in the Perovskite Database Project. Our algorithm filtered the data, grouped the relevant experiments according to their encapsulation type and compared their average lifetime indicator values. We conclude that encapsulation schemes with Al₂O₃ thin films and glass-on-glass with butyl rubber-based sealant yielded improved stability compared with other studied encapsulations. The frequently used glass-on-glass encapsulation with epoxy sealing yielded comparable PSC stability to glass-on-glass encapsulation with other sealants. Inorganic-based encapsulation schemes mostly showed improved PSC stability compared with organic cover materials. As more data are added to the Perovskite Database, our code can be used for updated and statistically more accurate comparison.