Dual-Sided Interface Optimization Enables High-Brightness All-Solution-Processed ZnMgO-Based Green Perovskite QLEDs
Hailong Feng1, Yunqian Zhao1, Feilong Yu1
1National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Key Laboratory for Special Functional Materials of Ministry of Education, School of Nanoscience and Materials Engineering, Henan University, Kaifeng, China.
Abstract:
The degradation of the underlying perovskite quantum dot (PQD) layers by the ZnMgO ink hinders the performance of all-solution-processed perovskite quantum dot light-emitting diodes (P-QLEDs). Herein, a novel dual-sided interface optimization is proposed for the fabrication of P-QLEDs: (i) cross-locking PQD surface ions with a robust zwitterionic ligand to boost their chemical and solvent tolerance; (ii) improving ink orthogonality via optimizing the solvent of ZnMgO to acetonitrile and eliminating residual hydroxyl groups from the ZnMgO surface. As a result, the ZnMgO is deposited on the PQD films without causing serious degradation, leading to improved carrier injection and radiative recombination. The optimized P-QLEDs achieve a maximum luminance of 134 920 cd m-2 and a peak external quantum efficiency (EQE) of 8.3%, ranking among the state-of-the-art all-solution-processed green-emitting devices.
