Transparent and flexible capacitor fabricated using a metal wire network as a transparent conducting electrode

Abstract

As transparency is becoming a desirable property even in non-optoelectronic devices, there is great impetus given to alternate materials and strategies replacing the conventional ITO. Here we have used transparent Au wire networks as electrodes, obtained from a crackle template method, in a capacitor where an ion gel serves as the dielectric. The transparent capacitor thus fabricated with flexible PET as substrate showed a capacitance of 20 μF cm⁻² at 1 Hz with average transmittance of ∼68% and was stable after many bending cycles. Such a performance is made possible due to high transmittance (∼86%) and low sheet resistance (∼4.2 Ω sq⁻¹) of the Au wire network. An ITO-free, flexible organic solar cell has also been fabricated using the Ag wire network.