Cost-effective silver ink for printable and flexible electronics with robust mechanical performance

An ideal silver precursor ink should be highly stable, transparent, and compatible with a broad range of substrates and facile fabricating techniques to provide a uniform electrodes with bulk conductivity at mild temperatures (<100 °C) for high performance electronic applications. Herein, we report a facile chemical route to develop the robust silver precursor ink having long stability, which possesses key characteristics of an optimal ink and provides a practical realization in flexible electronics via multiple techniques. The obtained transparent silver ink offers an unambiguously unique and economical approach towards printable electronic devices. The silver electrodes are fabricated by silver ink nozzle-jet printing and ink-pen writing that demonstrate remarkable conductivities (106–107 S/m) close to bulk silver (∼107 S/m) after annealing at 70–100 °C. The adhesion and conductivity of printed silver is highly stable in various mechanical bending. High quality nano-crystalline and pin holes free silver patterns are observed on flexible PET and PI substrates. The probable mechanism for formulated silver ink is elucidated. The precursor ink formulation process can possibly eliminate the need for costlier methods such as gravure printing and paves the way to industrial manufacturing of prudent electronic devices.