A comprehensive review of blue-emissive perovskites: mechanisms for regulating structural, electronic, and luminescent properties

Abstract

In recent years, metal halide perovskites have gained increasing research interest owing to their direct and tunable bandgaps, narrow emission bandwidths, and high carrier mobilities, main properties that stem from their significant application potential in the optoelectronics field. Notably, the crystalline structure, electronic characteristics, and luminescent properties of these perovskites can be effectively regulated through doping and ligand modification, thereby contributing to the improved performance of optoelectronic devices. This review intends to present an up-to-date overview of this rapidly advancing field, summarizing the latest research progress and practical applications of such perovskites in the fabrication of halide perovskite-based light-emitting diodes (PeLEDs). At present, the quantum efficiencies of PeLEDs are well over 20% for the red, green, and near-infrared bands and beyond. However, the optical properties of blue PeLEDs lag far behind their counterparts due to the crystalline structure. In this review, we first systematically explore the structure and unique physical properties of blue-emitting perovskite materials and then further discuss the current core challenges in the field by reviewing the innovative strategies and research breakthroughs. Finally, we conclude that ligand passivation is a promising option for improving the device efficiency and stability and give a potential outlook in the field of blue PeLEDs.