Author: João Resende
Co-Authors: João Resende, Dorina T. Papanastasiou, Dominik C. Moritz, Nil Fontanals, Carmen Jiménez, David Muñoz-Rojas, Daniel Bellet
Silver nanowire networks are extensively studied due to their excellent optical and electrical properties and exceptional flexibility. These networks constitute a promising candidate for transparent and flexible electrode applications. However, they can degrade under electrical or thermal stresses, so the understanding of the degradation mechanism is crucial for the integration of these metallic nanostructures in devices. In the present work, the electrical resistance of about 200 silver nanowire networks was monitored in situ to study the failure mechanisms under constant electrical current and temperature to assess the prevailing stress in the failure process. For both origins of failure, electrical and thermal, the temperature-induced instabilities appear to be the prevailing phenomena at the origin of the network degradation. A semi-empirical physical model is proposed considering the generated Joule heating and the effect of the imposed temperature. This model allows calculation of the time of failure of silver nanowire networks for different electrical and thermal applied conditions and network densities, showing good agreement with experimental data. The proposed model provides a deeper insight and constitutes a quantitative prediction tool for stability assessment, thus contributing to propel the integration of nanowire networks into devices as transparent electrodes due to their robustness and reliability.