Synthesis of WOn‐WX2 (n=2.7, 2.9; X=S, Se) Heterostructures for Highly Efficient Green Quantum Dot Light‐Emitting Diodes

• Published in: Angewandte Chemie International Edition Vol. 56; no. 35; pp. 10486 - 10490
• Main Authors: Han, Shikui, Yang, Xuyong, Zhu, Yihan, Tan, Chaoliang, Zhang, Xiao, Chen, Junze, Huang, Ying, Chen, Bo, Luo, Zhimin, Ma, Qinglang, Sindoro, Melinda, Zhang, Hao, Qi, Xiaoying, Li, Hai, Huang, Xiao, Huang, Wei, Sun, Xiao Wei, Han, Yu, Zhang, Hua
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 21-08-2017
• Edition: International ed. in English
• Subjects: Heterostructures; Inorganic materials; Light emitting diodes; Nanomaterials; Nanoparticles; Nanotechnology; Nanowires; Optoelectronics; Organic light emitting diodes; Quantum dots; Quantum efficiency; Selenium; sulfur; Sulfurization; Synthesis; tungsten
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201705617

Preparation of two‐dimensional (2D) heterostructures is important not only fundamentally, but also technologically for applications in electronics and optoelectronics. Herein, we report a facile colloidal method for the synthesis of WOn‐WX2 (n=2.7, 2.9; X=S, Se) heterostructures by sulfurization or selenization of WOn nanomaterials. The WOn‐WX2 heterostructures are composed of WO2.9 nanoparticles (NPs) or WO2.7 nanowires (NWs) grown together with single‐ or few‐layer WX2 nanosheets (NSs). As a proof‐of‐concept application, the WOn‐WX2 heterostructures are used as the anode interfacial buffer layer for green quantum dot light‐emitting diodes (QLEDs). The QLED prepared with WO2.9 NP‐WSe2 NS heterostructures achieves external quantum efficiency (EQE) of 8.53 %. To our knowledge, this is the highest efficiency in the reported green QLEDs using inorganic materials as the hole injection layer.
Sulfur green: Sulfurization or selenization of WOn nanomaterials gives WOn‐WX2 (n=2.7, 2.9; X=S, Se) heterostructures. Highly efficient green quantum dot light‐emitting diodes (QLEDs) have been prepared by using the as‐prepared WOn‐WX2 heterostructures as the hole‐injection layer.