Effect of perovskite film morphology on device performance of perovskite light-emitting diodes

Organic-inorganic hybrid perovskite materials have attracted significant attention in the last few years owing to their high photoluminescence quantum efficiency (PLQE) (of approximately 100%), narrow emission with a low full-width at half maximum (FWHM), and tunable optical bandgaps over the entire visible spectral range. Thus, perovskite materials are regarded as next-generation candidates for light-emitting diode application. Recently, perovskite light-emitting diodes (PeLEDs) with an external quantum efficiency of more than 20% have been successfully fabricated. Moreover, the efficiency and stability of PeLEDs have been significantly improved with the use of high-quality, uniform perovskite films. Here, the recent progress in the morphological control of perovskite films used in PeLEDs is reviewed. The current strategies involved in the morphological control of perovskite films to improve the device performance and long-term stability of PeLEDs via perovskite film modification, interface engineering, and quasi 2D-perovskite, are discussed.