Transparent and Flexible Supercapacitors with Networked Electrodes

Transparent and flexible energy storage devices have received immense attention due to their suitability for innovative electronics and displays. However, it remains a great challenge to fabricate devices with high storage capacity and high degree of transmittance. This study describes a simple process for fabrication of supercapacitors with ≈75% of visible transparency and areal capacitance of ≈3 mF cm−2 with high stability tested over 5000 cycles of charging and discharging. The electrodes consist of Au wire networks obtained by a simple crackle template method which are coated with MnO2 nanostructures by electrodeposition process. Importantly, the membrane separator itself is employed as substrate to bring in the desired transparency and light weight while additionally exploiting its porous nature in enhancing the interaction of electrolyte with the active material from both sides of the substrate, thereby enhancing the storage capacity. The method opens up new ways for fabricating transparent devices. Transparent and flexible supercapacitors based on Au/MnO2 network structure using simple fabrication steps are successfully assembled in new configurations exhibiting ≈75% transmittance 3 mF cm−2 areal capacitance with excellent cycling stability even after 5000 cycles of charging and discharging.