Metal-free SWNT/carbon/MnO2 hybrid electrode for high performance coplanar micro-supercapacitors

In this work, we report on superior coplanar micro-supercapacitors (MSCs) where single-wall carbon nanotube (SWNT)/carbon and SWNT/carbon/MnO2 are employed as the current collectors and hybrid electrodes, respectively. A composite of high dense SWNT network and photoresist is firstly patterned on the substrate and a followed carbonization process converts the photoresist into amorphous carbon to form the SWNT/carbon current collectors which demonstrates good conductivity and superior electrochemical performance. In addition, MnO2 nanostructures are uniformly grown on the carbon collectors to significantly increase the specific capacitance of the MSCs. It is found that the MSCs with SWNT/carbon/MnO2 hybrid electrodes show an excellent electrochemical performance with a high stack capacitance of 20.4 F cm(-3) and an outstanding cycling performance, i.e., 92.4% of the initial capacitance after 5000 cycles. In addition, the as-prepared hybrid electrodes could be transferred to a soft substrate so that the designed coplanar MSCs can serve as a power source to be integrated with flexible microelectronic devices. (C) 2016 Elsevier Ltd. All rights reserved.