Analysis of Color Alteration as a Novel Degradation Assessment Method for Perovskite Solar Cells

In this study, we present a non-invasive, in situ method of assessing the degradation of perovskite solar cells (PSCs) by analyzing color alterations. We utilized a custom-built photographing chamber with controlled light conditions paired with a high-resolution digital camera. This method offers a cost-effective solution for assessing degradation and could simplify the monitoring process across a range of PSCs. Unencapsulated, hole transport layer-free carbon-based PSCs (C-PSCs) and metal-based PSCs (Au-PSCs) were aged following an ISOS protocol (D-1, dark storage) for 9200 hours at an average temperature of 22 ± 1°C and humidity of 40 ± 20%. Periodic digital photographs and short-circuit current density (JSC) measurements were taken to map electrical performance against color change. A statistically significant correlation (r = 0.8 for C-PSCs, r = -0.7 for Au-PSCs) was found between color alterations and JSC. These findings suggest that color changes can serve as reliable indicators of PSC degradation.