Recent Advances in Flexible Perovskite Light-Emitting Diodes

Flexible perovskite light-emitting diodes (f-PeLEDs) have demonstrated their great potential for next-generation lighting and wearable display technologies due to their high color purity, excellent optoelectronic performance, solution processability, as well as their ultrathin and lightweight nature. Currently, the external quantum efficiency (EQE) and device stability of perovskite light-emitting diodes (PeLEDs) have been constantly updated in the past decade. However, limited by the inherent defect of perovskite and poor interfacial contact, the EQE of f-PeLEDs is still far lower than that of devices on rigid glass substrates. Therefore, it is necessary to provide an insightful summary to promote their further development. This review summarizes the strategies and the latest progress in improving the optoelectronic and mechanical performance of f-PeLEDs through the optimization of flexible substrates and electrodes, hole transport layers, perovskite layers, and fabrication techniques. Finally, this work summarizes and discusses the development and future challenges of flexible light-emitting diodes in the display field.