Surface engineering of ZnO nanoparticles with diethylenetriamine for efficient red quantum-dot light-emitting diodes

Dandan Zhang; Yan-Hua Liu; Lianqing Zhu

doi:10.1016/j.isci.2022.105111

Surface engineering of ZnO nanoparticles with diethylenetriamine for efficient red quantum-dot light-emitting diodes

iScience. 2022 Sep 11;25(10):105111. doi: 10.1016/j.isci.2022.105111. eCollection 2022 Oct 21.

Authors

Dandan Zhang¹, Yan-Hua Liu², Lianqing Zhu¹

Affiliations

¹ Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing 100192, P. R. China.
² School of Optoelectronic Science and Engineering, Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province & Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou, Jiangsu 215006, P. R. China.

Abstract

Due to the outstanding electron injection/transport capability of ZnO nanoparticles (NPs), quantum-dot light-emitting diodes (QLEDs) are commonly constructed by employing a hybrid device structure with ZnO electron-transporting layer and organic hole-transporting layer. However, the emission quenching of quantum dots and excessive electron injection induced by ZnO NPs also limits the device efficiency and operational stability. Here, diethylenetriamine (DETA) molecules as the ligands are introduced to modify the surface of ZnO NPs, which not only passivate the surface defects of ZnO but also suppress the overwhelming electron injection in the QLED. As a result, the device based on the DETA-modified ZnO NPs exhibits a peak external quantum efficiency of 23.7%, corresponding to an enhancement factor of 129% in comparison with that of the device with as-synthesized ZnO as the electron-transporting layer. The easy and feasible strategy may also be applicable to other photoelectric devices, such as solar cells and photodetectors.

Keywords: Devices; Engineering; Nanomaterials.