A new type of porous graphite foams and their integrated composites with oxide/polymer core/shell nanowires for supercapacitors: Structural design, fabrication, and full supercapacitor demonstrations

We attempt to meet the general design requirements for high-performance supercapacitor electrodes by combining the strategies of lightweight substrate, porous nanostructure design, and conductivity modification. We fabricate a new type of 3D porous and thin graphite foams (GF) and use as the light and conductive substrates for the growth of metal oxide core/shell nanowire arrays to form integrated electrodes. The nanowire core is Co₃O₄, and the shell is a composite of conducting polymer (poly(3,4- ethylenedioxythiophene), PEDOT) and metal oxide (MnO₂). To show the advantage of this integrated electrode design (viz., GF + Co₃O ₄/PEDOT-MnO₂ core/shell nanowire arrays), three other different less-integrated electrodes are also prepared for comparison. Full supercapacitor devices based on the GF + Co₃O₄/PEDOT- MnO₂ as positive electrodes exhibit the best performance compared to other three counterparts due to an optimal design of structure and a synergistic effect.