Tailored Surface Defect Passivating Materials for Efficient and Metal Halide Perovskite Light-Emitting Diodes

Halide-based perovskite materials have been spotlighted in light-emitting diodes and perovskite solar cells applications owing to their excellent optical and electrical characteristics that enable a remarkable enhancement of device efficiency. Excellent film quality of perovskite with defect passivation is required to obtain highly efficient and stable perovskite optoelectronic devices. However, defect sites such as voids, pinholes, grain boundaries and under-coordinated ions, creating many undesired electronic trap sites can exist in solution-processed perovskite films. Here, we deal with the various problems that originated from surface defects of MHPs and suggest strategic approach of surface defect passivating materials for device efficiency and stability enhancement of perovskites.