In-situ Visual Microdamage Detection in Lead-based Perovskite Solar Cells

Abstract

Although Lead (Pb)-based perovskite solar cells (PSCs) have garnered intense attention for their remarkable photovoltaic conversion efficiency, their commercial process is urgently in need of an effective damage-evaluation system for the early diagnosis of faulty PSCs. The main cause of microdamage in perovskite films is the outflow of Pb, which significantly impacts device performance. However, no reliable correlation has been established between classical damage detection techniques and Pb detection, resulting in limited detection sensitivity. Here, we report an in-situ visual microdamage evaluation method of PSCs by coating the device surface with a silica gel encapsulation layer containing porphyrin molecules. This detection technology enables high selectivity and sensitivity based on the strong complexation between the porphyrin ring and trace Pb outflow from degraded PSCs. By establishing the linear relationship between the fluorescence intensity and Pb concentration in PSCs, trace Pb outflow is pinpointed and quantified with a low detection limit of 0.65 μg cm−2. An applet is developed for the in-situ visual fluorescence detection method to facilitate the continuous real-time monitoring of series-type PSCs, thereby enabling the prompt identification and replacement of damaged PSCs and ensuring the swift restoration of high efficiency.