Stability enhancement of perovskite solar cells via multi-point ultraviolet-curing-based protection

As efficiency approaches the limit, it becomes more urgent to solve the toxicity and instability of organometal halide perovskite solar cells (PSCs), which asks for enhancement by applying methods that majorly contribute to stability itself to help prevent device from suffering from harmful matters. In this paper, we introduce a simple ultraviolet (UV) curing recipe which contains ethoxylated trimethylolpropane triacrylate (ETPTA) and 2-hydroxy-2-methyl-1-phenyl-1-propanone. ETPTA is polymerized by UV-curing and is applied as additive rather than as encapsulation material to distribute around the perovskite as a cross-linked network. Suitable amount of UV-gel added in perovskite precursor solution and hole transport material solution during device fabrication could promotes the crystallization of perovskite, reduce the diffusion of moisture in hole transport layer and therefore avoid degradation of PSCs. Notable protection happens with a volume percentage of ETPTA no more than 0.5%, especially in ambient conditions with humidity larger than 60%.

Automated summary

This paper introduces a method to enhance the stability of organometal halide perovskite solar cells (PSCs) using UV-curing. By adding a suitable amount of UV-gel in the perovskite precursor solution and hole transport material solution, the crystallization of perovskite can be promoted, moisture diffusion in the hole transport layer can be reduced, and the degradation of PSCs can be avoided.