Air-processed stable near-infrared Si-based perovskite light-emitting devices with efficiency exceeding 7.5%

Abstract

Organic perovskite materials have attracted considerable attention because of their potential applications in various types of opto-electronic devices. Nowadays, obtaining high-performance devices fabricated in ambient atmosphere is a challenge. In this study, we report Si-based near-infrared (NIR) perovskite light-emitting devices (PeLEDs) with enhanced efficiency by an air-processed technique with two composite layers. One layer is constructed using 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP) with poly-TPD coating as a hole transport layer (HTL) to balance carrier injection, and the other is constructed doping poly(methyl methacrylate) (PMMA) with antisolvent to passivate defects and protect MAPbI₃ from degradation by water and oxygen. Through these two composite layers, the EL performance is enhanced with an external quantum efficiency (EQE) of 7.5%, and the stability is also improved to 200 min after the introduction of another m-PMMA layer. Our results provide a simple way to manufacture high-efficiency and stable PeLEDs under air condition.