Engineering of Hole Transporting Interface by Incorporating the Atomic-Precision Ag<sub>6</sub> Nanoclusters for High-Efficiency Blue Perovskite Light-Emitting Diodes
Fujun Zhang, Yanbo Gao, Po Lu, Yuan Zhong, Yue Liu, Xinyu Bao, Zehua Xu, Min Lu, Yanjie Wu, Ping Chen, Junhua Hu, Yù Zhang, Zhennan Wu, Hongwei Song, Xue Bai
Abstract
Properties of the underlying hole transport layer (HTL) play a crucial role in determining the optoelectronic performance of perovskite light-emitting devices (PeLEDs). However, endowing the current HTL system with a deep highest occupied molecular orbital (HOMO) level concurrent with high hole mobility is still a big challenge, in particular being an open constraint toward high-efficiency blue PeLEDs. In this regard, employing the poly(9-vinylcarbazole) as a model, we perform efficient incorporation of the atomic-precision metal nanoclusters (NCs), [Ag 6 PL 6, PL = ( S )-4-phenylthiazolidine-2-thione], to achieve significant tailoring in both HOMO energy level and hole mobility. As a result, the as-modified PeLEDs exhibit an external quantum efficiency (EQE) of 14.29% at 488 nm. The presented study exemplifies the success of metal NC involved HTL engineering and offers a simple yet effective additive strategy to settle the blue PeLED HTL dilemma, which paves the way for the fabrication of highly efficient blue PeLEDs.