Lead‐Free Perovskite Light‐Emitting Diodes

Metal halide perovskites have been identified as a promising class of materials for light-emitting applications. The development of lead-based perovskite light-emitting diodes (PeLEDs) has led to substantial improvements, with external quantum efficiencies (EQEs) now surpassing 30% and operational lifetimes comparable to those of organic LEDs (OLEDs). However, the concern over the potential toxicity of lead has motivated a search for alternative materials that are both eco-friendly and possess excellent optoelectronic properties, with lead-free perovskites emerging as a strong contender. In this review, the properties of various lead-free perovskite emitters are analyzed, with a particular emphasis on the more well-reported tin-based variants. Recent progress in enhancing device efficiencies through refined crystallization processes and the optimization of device configurations is also discussed. Additionally, the remaining challenges are examined, and propose strategies that may lead to stable device operation. Looking forward, the potential future developments for lead-free PeLEDs are considered, including the extension of spectral range, the adoption of more eco-friendly deposition techniques, and the exploration of alternative materials.