Scalable Passivation of Perovskite Solar Cells Using Evaporated CsPbCl3

Abstract

The suboptimal interfacial quality between the perovskite absorption layer and the electron-transport layer constrains the performance of perovskite solar cells. Introducing an interface passivation layer is generally recognized as an effective method for addressing this issue. A uniform passivation film with a large area can be prepared using an evaporation technique. In this study, we designed and fabricated an inorganic CsPbCl₃ passivation layer by the coevaporation of PbCl₂ and CsCl. The evaporated passivator exhibited excellent interface passivation effects and a relatively low thickness sensitivity to device performance. As a result, the open-circuit voltage of perovskite solar cells with a 1.68 eV perovskite absorber was improved by nearly 100 mV, and the device efficiency achieved was 21.84%, ranking as the highest efficiency based on the hybrid evaporation-solution method. The proposed passivation approach has potential applications in large-area perovskite solar cells.