Strategies to Improve Luminescence Efficiency and Stability of Blue Perovskite Light‐Emitting Devices

Abstract

Metal halide perovskite materials hold great potential as a core element in full‐color display and lighting applications due to their unique optoelectronic properties, such as high photoluminescence efficiency, good color purity, tunable bandgap, and low‐temperature solution processability. However, the performance of blue perovskite light‐emitting diodes (PeLEDs) lags far behind their red and green counterparts, impeding their practical use. Herein, the recent progress on blue PeLEDs based on different restrictions and some feasible strategies to improve luminescence efficiency and stability are summarized. The methods to optimize blue‐emission perovskite materials with different dimensions are addressed. The major factors affecting luminescence stability, the approaches to balance charge injection and minimize the optical loss are also discussed. Several problems in blue PeLEDs, particularly the toxicity of lead‐based perovskites and the alternative solutions of lead‐free perovskites, are emphasized. Finally, the perspective of future development in blue PeLEDs is provided.

Micro–Nanostructure‐Assisted Luminescence in Perovskite Devices

“…As to stimulated emission of perovskite films, intrinsic perovskite cavities, processed perovskite cavities, and extrinsic auxiliary cavities are widely applied in perovskite lasers featuring low threshold and high‐Q factor. It is worth noting that the applications of micro–nanostructures in MHP materials and their correlated devices have been extensively reviewed, [ 33,104,120–125 ] indicating the great importance of micro–nanostructures in this field.…”

Interfacial Nucleation Seeding for Electroluminescent Manipulation in Blue Perovskite Light‐Emitting Diodes

“…[1][2][3][4][5][6][7] In recent years, the device performance of perovskite light-emitting diodes (PeLEDs) has been substantially improved by manipulating the perovskite microstructures through various strategies, such as stoichiometry control, defect passivation, and dimensional engineering. [8][9][10][11][12][13][14] Upon the optimization of the perovskite emitter, the external quantum efficiencies (EQE) over 20% has been realized for PeLEDs with green, red, and near-infrared emissions. [8][9][10][11] Unfortunately, the low efficiency of blue PeLEDs with EQE lower than 13% is still a critical drawback, impeding their practical applications in full-color display and solid-state lighting.…”

“…[8][9][10][11][12][13][14] Upon the optimization of the perovskite emitter, the external quantum efficiencies (EQE) over 20% has been realized for PeLEDs with green, red, and near-infrared emissions. [8][9][10][11] Unfortunately, the low efficiency of blue PeLEDs with EQE lower than 13% is still a critical drawback, impeding their practical applications in full-color display and solid-state lighting. [15][16][17][18][19][20][21] It is, therefore, an urgent demand to boost the device efficiency of blue PeLEDs.…”

In situpassivation of Pb0traps by fluoride acid-based ionic liquids enables enhanced emission and stability of CsPbBr3nanocrystals for efficient white light-emitting diodes

“…1–5 However, their intrinsic instability and easy degradability in air and humid environments have become the main bottleneck for their industrialization and commercialization. 6–8 It is a prerequisite to explore effective approaches to improve the long-term stability of CsPbX 3 NCs while maintaining superior optoelectronic properties.…”