Impact of Light on the Thermal Stability of Perovskite Solar Cells and Development of Stable Semi-transparent Cells

Abstract

The stability of perovskite cells has been the major challenge to the commercialization of the technology. Here, we study the thermal stability of mesoporous perovskite cells using poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) for the hole transport layer. We find evidence that gold diffusion into the perovskite active layer is prevented by the PTAA layer when the cell is aged at 85~{mathbf {o}}C in the dark, but not under light. This seriously affects the operational stability of perovskite cells. We therefore develop thermally stable semi-transparent perovskite cells, which retain more than 90% of the initial efficiency after 160 hours operating at 85 {mathbf {o}}\textbf{C} under light.