High-performance, ultra-flexible and transparent embedded metallic mesh electrodes by selective electrodeposition for all-solid-state supercapacitor applications

A novel approach to fabricate large-scale embedded metallic mesh transparent conductive electrodes (TCEs) on flexible substrates via a low-cost and facile selective electrodeposition process combined with inverted film-processing methods is proposed for the first time. The optimized embedded Ni mesh TCEs on polyethylene terephthalate (PET) exhibit excellent optoelectronic properties (R-s similar to 0.2 Omega sq(-1) & T similar to 84%), high figure of merit (FOM similar to 1.0 x 10(4)) and mechanical durability properties, which arise from the embedded inverted T-type shape of the electrodeposited Ni mesh. The resultant embedded Ni mesh/ polymer poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) hybrid electrodes are utilized both as current collectors and active electrode materials for all-solid-state flexible transparent supercapacitors, which show high transparency, superior electrochemical performances, excellent mechanical flexibility and high capacitance retention. Even after 1000 cycles of repetitive bending with a radius of 2 mm, the capacitance exhibited a decrease within only 5.2%. The high performance can be attributed to the excellent optoelectronic properties of embedded Ni mesh electrodes in combination with superior electrochemical properties of PEDOT: PSS. This provides a simple, cheap and controllable method for fabricating high-performance flexible TCEs and thus constructing flexible and transparent energy conversion and storage devices and systems.