Concave and Convex Bending Influenced Mechanical Stability in Flexible Perovskite Solar Cells
Liying Pei, Haomiao Yu, Qi Zhang, Jinpeng Li, Kai Wang, Bin Hu
Abstract
Flexible perovskite solar cells (F-PSCs) have shown great potential application towards future wearable power sources with increasing power conversion efficiency (PCE) and mechanical stability. In this study, we found that the mechanical stability of F-PSCs is also influenced by the way of mechanical bending. The F-PSCs exhibit better mechanical stability with concave bending as compared with the ones with convex bending. Further study based on J–V characteristics and impedance spectra indicate that the series resistance (Rs) of the device has a larger increase, which results in the degradation of photovoltaic performance after convex bending. Furthermore, it is revealed that the conductivity decrease of perovskite film is responsible for the increased Rs, consequently leads to poorer mechanical stability after convex bending. Our findings may attract the attention of developing the standard of characterizing mechanical stability in the flexible perovskite-based devices.