A comparative Study on the Stability and Degradation of Perovskite Solar Cells

Abstract

This study aims to investigate the environmental factors that affect the performance and long-term stability of the perovskite solar cells (PSCs). PSCs are based on organometallic halides (perovskites) that act as a light-sensitive compound that produces excitons when placed under the light. However, PSCs have a limited operating lifetime due to the degradation of the perovskite layer. There are many factors like moisture, UV light, and temperature that lead to the degradation of the perovskite layer. The presence of moisture causes an irreversible degradation of the perovskite layer. The performance and the long-term stability of the solar cells were investigated. The structure of the PSC used in this study contains the Transparent Conductive Oxide (TCO), electron transport layer (TiO2), perovskite absorber, hole transport layer, and the conductive metallic silver layer. The solar cells were investigated under various environmental conditions like controlled humidity (30% to 38% RH), high humidity (>50% RH), nitrogen under room temperature of 22°C, and nitrogen under elevated temperature at 80°C. The properties of solar cells studied are the optical absorption of the perovskite absorber, the open-circuit voltage (VOC), short circuit current (ISC), fill factor (FF), and efficiency of the PSCs. The solar cells were stored under light with controlled humidity (30% to 38% RH), high humidity (>50% RH), nitrogen under room temperature of 22°C and elevated temperature of 80°C. Each solar cell under different environments was tested as a function of time. It was found that high humidity, elevated temperature, and presumably the UV part of the white light caused the solar cell to degrade rapidly. It was seen that the nitrogen atmosphere with a room temperature of 22°C had the best environment for storing the perovskite solar cell.