Patterned Sandwich-Type Silver Nanowire-Based Flexible Electrode by Photolithography

• Published in: ACS applied materials & interfaces Vol. 13; no. 51; pp. 61463 - 61472
• Main Authors: Kim, Young Un, Kwon, Na Yeon, Park, Su Hong, Kim, Chai Won, Chau, Hong Diem, Hoang, Mai Ha, Cho, Min Ju, Choi, Dong Hoon
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 29.12.2021
• Subjects: Organic Electronic Devices; transparent electrode; bending stability; silver nanowires; patterned electrode; flexible electrode
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.1c19164

Silver nanowires (AgNWs) are one of the important flexible electrode material candidates that can replace brittle indium tin oxide (ITO). In this work, we demonstrated novel patterned sandwich-type AgNW-based transparent electrodes easily prepared using the photolithography method for application in flexible devices. A cross-linked underlayer was introduced to increase the adhesion properties between a poly­(ethylene terephthalate) substrate and AgNWs, and as a result, a uniform AgNW layer was easily deposited. Finally, the AgNW layer could be easily patterned by introducing a photocross-linkable upper layer without lift-off, dry transfer, and removal methods. A mixture of poly­(sodium-4-styrene sulfonate) (PSS–Na+) and 2,4-hexadiyne-1,6-diol (HDD), which is a component of the upper layer, exhibited good cross-linking properties as well as excellent adhesion to the AgNW layer. Through the above method, it was possible to easily fabricate a patterned electrode with smooth surface morphology. Moreover, AgNW-based patterned electrodes exhibit good optical and electrical properties (R s = 29.8 Ω/□, T 550 nm = 94.6%), making them suitable for optoelectronic devices. Flexible polymer solar cells (PSCs) using patterned AgNW electrodes showed a high power conversion efficiency of over 10%, which is comparable to that of PSCs using rigid ITO electrodes. In addition, the high mechanical stability of AgNW-based PSCs was confirmed by bending experiments.