Deformation mechanisms of nanoporous flexible transparent electrodes based on particle-free silver inks

Abstract

In this work, we explore the relationships between the morphology, deformation behavior, and functionality of transparent electrodes based on metal-organic decomposition (MOD) silver inks on PET substrates. A self-organized nanoporous microstructure with good interconnectivity of silver ligaments is shown to provide the necessary optical transparency and sufficient conductivity of the electrode. Tensile tests with in-situ resistance measurements revealed moderate resistance increase with increasing applied strain, indicating the suitability of the coatings for flexible electronics applications. With the help of in-situ scanning electron microscopy in combination with digital image correlation, it is demonstrated that cracks which are generated during a tensile test are short and isolated, which is beneficial for good electromechanical stability during monotonic and cyclic loading. In contrast to alternative methods for synthesis of nanoporous ultrathin films, the demonstrated transparent electrode is fabricated by a single printing-curing process under very low consumption of particle-free MOD ink, thus being suitable for cost-effective mass production.