Multi-color afterglow from amorphous hybrid perovskites for flexible, programmable heterostructured composites

Abstract

Organic–inorganic hybrid perovskites (OIHPs) with ultralong organic phosphorescence (UOP) have attracted considerable attention because of their unique optical properties and long phosphorescence lifetimes. However, the development of amorphous UOP perovskites with excellent processability remains a significant challenge. Herein, N-aminoethyl piperazine is employed as a non-conjugated ligand to synthesize amorphous Cd-based OIHPs (named AC-A), which exhibit white-light emission and green phosphorescence originating from clusters formed by organic ligands. Owing to their ultralong phosphorescence lifetime, the AC-A perovskites display a long green afterglow lasting for up to 8 s. The afterglow color can be tuned to orange and red by doping inorganic and organic guest species, respectively. Furthermore, flexible and adhesive thread-like heterostructured composites with different afterglow colors are prepared by coating polylactic acid on AC-A and are successfully applied in a programmable information encryption system. This work not only utilizes rigid inorganic octahedra to protect organic clusters and achieve UOP in amorphous hybrid perovskites but also provides a novel design strategy and example for the development of amorphous, flexible cluster luminescent materials with multi-color afterglow.