Ultrastable near-infrared perovskite light-emitting diodes

Abstract

Perovskite light-emitting diodes are an emerging light source technology. However, similar to perovskite solar cells, poor operational stability remains an obstacle for commercial applications. Here we demonstrate ultrastable and efficient near-infrared (~800 nm) perovskite light-emitting diodes with record-long operational lifetimes (T50, extrapolated) of 11,539 h (~1.3 years) and 32,675 h (~3.7 years) for initial radiance (or current densities) of 3.7 W sr−1 m−2 (~5.0 mA cm−2) and 2.1 W sr−1 m−2 (~3.2 mA cm−2), respectively, with even longer lifetimes forecasted for lower radiance. Key to this stability is the introduction of a dipolar molecular stabilizer, which interacts with the cations and anions at the perovskite grain boundaries. This suppresses ion migration under electric fields, preventing the formation of lead iodide, which mediates the phase transformation and decomposition of α-FAPbI3 perovskite. These results remove the critical concern that halide perovskite devices may be intrinsically unstable, paving the path towards industrial applications.