Flash-welded ultraflat silver nanowire network for flexible organic light-emitting diode and triboelectric tactile sensor
Hee Seung Wang, Tae Hong Im, Young Bin Kim, Sang Hyun Sung, Seongwook Min, Sang Hyun Park, Han Eol Lee, Chang Kyu Jeong, Jung Hwan Park, Keon Jae Lee
Abstract
Transparent flexible electrodes of metallic nanowire have been spotlighted to develop form factor free electronics for human-machine interfaces. However, state-of-the-art nanowire electrodes have been restricted for flexible application due to multi-stacked morphology with large protrusion and high surface roughness, which generate critical leakage current and device malfunction. Light-material interactions using board-wavelength flash lamps can be a solution for outstanding electrical and morphological properties by inducing a plasmonic welding of flexible metal nanowire. Herein, we propose flash-welded ultraflat electrode networks enabled by nanowire embedding to reduce the protrusion and surface roughness. The nanowire embedded in elastomer presented an ultra-smooth surface of Rq ~ 1.4 nm that prevents leakage current in ultrathin flexible electronics. The excellent electrical properties of ultraflat composite electrode were realized by xenon flash-induced junction welding of metal nanowire. The mechanical stability of flash-welded electrode was confirmed by sheet resistance value under cyclic bending test. Finally, ultraflat silver nanowire networks were utilized in practical application of a leakage current-free flexible optoelectronic device and a triboelectric tactile sensor.