Eco-Friendly All Water-Based Solution Process for Robust Ag Nano-Mesh Transparent Electrodes

Transparent conducting electrodes have attracted substantial attentions as an essential component of various optoelectronic devices. Recently, the grid-structured metal mesh electrodes are considered as highly efficient transparent electrodes that possess high optical transmittance while maintaining sufficient electrical conductivity and are suitable for flexible conductors with isotropic electrical conductivity. Here, we report a simple and effective approach for the fabrication of highly transparent Ag nano-mesh prepared by all water-based solution process. The Ag mesh electrodes were formed by combination of colloidal gold nanoparticles deposition and silver enhancement. The optical and electrical properties of the Ag mesh can be finely tuned by varying condition of gold nanoparticle deposition and silver enhancement. The smallest feature size of the obtained metal mesh patterns is about 700 nm with a thickness of 30-60 nm. The transparent electrodes with the Ag nano-mesh structure exhibit not only excellent electrical conductivity with a sheet resistance of 70 Ω/sq at a transmittance of 96.2% but also strong adhesion strength to substrate which is confirmed by peeling off test. Our all water-based solution processed metal mesh electrodes is applied to transparent heater which is able to heat up to 250 °C at 7 V. Through this study, Not only fabrication of high performance metal mesh but also low cost fabrication without any hazardous wastes is succeeded. This research was funded and conducted under [the Competency Development Program for Industry Specialists] of the Korean Ministry of Trade, Industry and Energy(MOTIE), operated by korea Insstitute for Advancement of Technology (KIAT). (No. P0012453, Next-generation Display Expert Training project for Innovation Process and Equipment, Materials Engineers)