Multifunctional Additives for Bright, Efficient and Stable Lead-bromide Perovskite LEDs

Perovskite light-emitting diodes (PeLEDs) show significant potential as a next-generation light source. While breakthroughs were made in near-infrared (NIR) PeLEDs simultaneously achieving high efficiency, high radiance and high stability, visible PeLEDs still lag behind and unable to meet the requirements for practical applications. The majority of efficient visible PeLEDs are based on low-dimensional perovskites, which show limited charge transport abilities and significant Auger recombination losses. Visible PeLEDs based on 3D perovskites typically show lower efficiencies. In this work, we report high-performance PeLEDs based on a 3D lead-bromide perovskite, showing a peak EQE of > 17% a high maximum luminance of > 10
⁵
cdm
⁻²
and a long operational lifetime (T
50
) of ∼ 20h at 1000cdm
⁻²
. We attribute the high performance to the introduction of a phosphorylcholine multifunctional additive, which regulates the crystallization process and reduces the density of pinholes in the 3D perovskite. Besides, it passivates the deep-level defects, greatly improving the photoluminescence quantum yield (PLQY) of the perovskite samples Our results show that suitably designed 3D bromide perovskites are a promising material platform for visible PeLEDs.