Self-Encapsulated Cu Grid for Highly Transparent Conductive Electrode for Transparent Heater and Electrochemical Supercapacitor Applications

The conducting metallic grid is a prominent viable candidate for an alternative to indium tin oxide for optoelectronic devices. This metallic grid tends to oxidize quickly, and to avoid oxidization, a passivation layer must be added, which drastically compromises the transmittance. The fabrication of a highly flexible, highly transparent, and conductive copper grid electrode with an outstanding sheet resistance of 0.11 ohm (-1), and excellent transparency of 93.13% is reported. This copper electrode resists oxidization with the help of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), and even after exposing the electrode to the ambient atmosphere, it shows excellent sheet resistance of 0.12 ohm (-1). This is achieved by the in situ formation of an oxidization-resistive light-absorbing PEDOT:PSS layer that encapsulates the Cu microparticles during electrodeposition. The electrode shows excellent mechanical stability with good electromagnetic interference shielding of 19 dB. Moreover, the electrode is developed as a thin film heater, and subjects to electrochemical analysis, which shows a specific capacitance of 81.58 mF cm(-2) for supercapacitor application.