Enhanced performance of perovskite light-emitting diodes with PEDOT:PSS/CsBr composite hole transport layer.

Perovskite light-emitting diodes (PeLEDs) are widely used in optoelectronics due to their excellent performance. The hole transport layer (HTL) plays a crucial role in the performance of the device. In this paper, we prepared quasi-two-dimensional perovskite light-emitting diodes with doping CsBr into PEDOT:PSS as a composite HTL, and investigated the optoelectronic properties of the devices. The maximum luminance of the CsBr-doped device was 6652 cd/m2 and the maximum current efficiency (CE) was 7.55 cd/A, which were increased by 112 % and 80 % compared with the undoped device, respectively. This is primarily due to the PEDOT:PSS/CsBr composite HTL optimizes the morphology of the perovskite film, passivates the defects of the perovskite film, and suppresses the exciton quenching at the HTL/perovskite emission layer (EML) interface. Meanwhile, CsBr doping helps to enhance the hole transport ability of HTL and thus increase the exciton recombination efficiency, which improves the device performance. The results in this paper can provide experimental support for the development of PeLEDs. • Optimized the hole transport layer (HTL) and prepared quasi-two-dimensional perovskite light-emitting diodes by doping CsBr into PEDOT:PSS. • Enhanced PL strength, suppresses exciton bursting at the HTL/emission layer (EML) interface. • Passivation of defects in perovskite films and enhancement of crystallinity. • Enhanced hole injection ability and exciton recombination efficiency in HTL. • Optimized PeLED's performance is improved in every way. [ABSTRACT FROM AUTHOR]