Kim Dong Hyun, Hwang Jeong Ha, Seo Eunyong, Lee Kyungjae, Lim Jaehoon, Lee Donggu
Department of Semiconductor Engineering, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam 52828, Republic of Korea.
Department of Energy Science, Centre for Artificial Atoms, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea.
ACS Appl Mater Interfaces. 2024 Aug 28;16(34):45139-45146. doi: 10.1021/acsami.4c07049. Epub 2024 Aug 1.
The operating lifetime of quantum-dot light-emitting diodes (QLED) is a bottleneck for commercial display applications. To enhance the operational stability of QLEDs, we developed a robust solution-processed highly conductive hole-transport-layer (HTL) structure, which enables a thick HTL structure to mitigate the electric field. An alternating doping strategy, which involves multiple alternating stacks of 4,4'-di(naphthalen-1-yl)-4,4'-bis(4-vinylphenyl)biphenyl-4,4'-diamine and phosphomolybdic acid layers, could provide significantly improved conductivity; more specifically, the 90 nm-thick alternatingly doped HTL exhibited higher conductivity than the 45 nm-thick undoped HTL. Therefore, when applied to a QLED, the increase in the thickness of the alternatingly doped HTL increased device reliability. As a result, the lifetime of the QLED with a thick, alternatingly doped HTL was 48-fold higher than that of the QLED with a thin undoped HTL. This alternating doping strategy provides a new paradigm for increasing the stability of solution-based optoelectronic devices in addition to QLEDs.
量子点发光二极管（QLED）的工作寿命是商业显示应用的一个瓶颈。为了提高QLED的运行稳定性，我们开发了一种坚固的溶液处理高导电空穴传输层（HTL）结构，该结构能使较厚的HTL结构减轻电场。一种交替掺杂策略，涉及4,4'-二（萘-1-基）-4,4'-双（4-乙烯基苯基）联苯-4,4'-二胺和磷钼酸层的多个交替堆叠，可以显著提高导电性；更具体地说，90纳米厚的交替掺杂HTL比45纳米厚的未掺杂HTL表现出更高的导电性。因此，当应用于QLED时，交替掺杂HTL厚度的增加提高了器件可靠性。结果，具有厚交替掺杂HTL的QLED的寿命比具有薄未掺杂HTL的QLED高48倍。这种交替掺杂策略为除QLED之外的基于溶液的光电器件提高稳定性提供了一种新范例。
