Luminescent and ultrastable perovskite-acrylate based elastomers with excellent stretchability and self-healing capability for flexible backlight display

All-inorganic lead halide perovskite nanocrystals (NCs) have received considerable attention due to their exceptional optoelectronic characteristics and photovoltaic performance, but their practical applications are restricted by their poor stability. Integrating multifunctionality such as high stability, outstanding flexibility, stretchability and self-healing capability has also been highly desired for flexible full-color displays, soft optical devices, and wearable applications. Here, we developed a facile one-pot photopolymerization strategy to produce highly stable self-healing CsPbBr3-based elastomers with outstanding flexibility, scalability, and stretchability. The obtained perovskite NCs (-10 nm; PLQY of 78%) were capped and passivated with bifunctional methacrylic acid ligands, which provided free double bonds on their surface. The CsPbBr3-based elastomers were obtained via the photo-induced copolymerization of functionalized CsPbBr3 NCs with methyl methacrylate (MMA) and n butyl acrylate (BA) at room temperature. This yielded homogenous CsPbBr3 nanocrystals (-10 nm) dispersed in the copolymer, which displayed a high photoluminescence quantum yield (PLQY > 70%). Versatile and specific luminescent shapes and patterns could be fabricated from the CsPbBr3-based elastomers by regulating the constituent content, reaction time, or molding process. The obtained CsPbBr3-based elastomers exhibited high air and water stability, high stretchability (-1300% elongation), tensile recovery (-100%), and excellent self healing capability, which also permitted twisting or bending. This facile photopolymerization strategy greatly expands the methods for fabricating highly stable perovskite materials with excellent stretchability and self healing properties for use in flexible optoelectronic devices.