Enhanced UV-light stability of organometal halide perovskite solar cells with interface modification and a UV absorption layer

Abstract

High power conversion efficiency (PCE) and long-term stability against ultraviolet irradiation and humidity for organometal halide perovskite solar cells (Pero-SCs) are challenging factors for the practical application of solar cells. Here, we report a facile strategy to enhance the long-term tolerance of Pero-SCs to UV light. A silane coupling agent was introduced between the electron collection layer and the CH₃NH₃PbI₃ perovskite absorber layer, while an ultraviolet absorber was adopted to block the UV radiation, which is detrimental to the stability of CH₃NH₃PbI₃. This device exhibits excellent performance and chemical stabilities, which result in the loss of 2.2% PCE on average. The unencapsulated devices retain over 80% of their initial efficiency even after continuous UV irradiation for 24 h (at 60% relative humidity), exhibiting greater UV-light tolerance and superior stability. This is a simple and effective approach to fabricate Pero-SCs with enhanced stabilities against UV radiation and the results confirm the influence of UV light on the efficiency, demonstrating a new method for the commercialization of Pero-SCs.