Near-Zero Transmittance Loss, Highly Durable, Flexible, Transparent Electrode with an Ultrathin Ag Nanoporous Structure

Recent advances in state-of-the-art optoelectrical and photovoltaic devices have necessitated further improvements in the efficiency of transparent electrodes by simultaneously minimizing electrical and optical losses, which remain technically challenging to achieve. In this study, we developed a strategy for constructing a highly efficient transparent electrode that retains near-perfect optical transparency at tunable wavelengths in the visible spectral range and has excellent electrical reliability against heavy processing loading. The optoelectrical features were achieved by integrating an ultrathin Ag nanoporous layer and a substoichiometric electron-transferring SiOx film in a multilayered oxide/metal/oxide configuration. Complete sealing of the Ag nanoporous geometry by a subsequently coated SiOx film facilitates near-zero optical transmittance loss (<1%, averaged at 0.7%) over a wide spectral range of 500–700 nm at a near-bulk resistivity of 7.2 × 10–8 Ω m while ensuring extreme durability against chemical corrosion, electrical/thermal degradation, and mechanical deformation. The unexpected performance of such a defective Ag-layered geometry, which has rarely been considered in the design of transparent electrodes, refutes conventional approaches that emphasize the implementation of a completely continuous layered geometry of Ag to optimize the optical and electrical performances. These results provide an alternative solution for maximizing the performance and durability of Ag-based transparent electrodes that can be synthesized on either glass or polymer substrates for various optoelectrical applications, including flexible transparent Joule heaters.