3D Porous Reduced Graphene Oxide Nanostructure As Electrode Materials for High Performance Flexible Gel-Type Supercapacitors

Abstract

Three-dimensional (3D) porous reduced graphene oxide nanostructure, termed starch/RGO, was prepared with a simple, fast, and scalable mix-and-heat process. The starch/RGO was composed of three-dimensionally well-connected reduced graphene oxide network glued together with starch derived carbon. The starch/RGO possessed several critical advantageous structural features, including well-dispersed, readily accessible micropores offering high specific surface areas and well-connected and highly conductive reduced graphene oxide network, making it an excellent electrode material for supercapacitors. The starch/RGO electrode performed well in both positive (0 – 1 V) and negative (-1 – 0 V) potential windows and was used to assemble flexible, gel-type symmetric supercapacitors. The starch/RGO//starch/RGO supercapacitor exhibited outstanding capacitive performances, excellent electrochemical reversibility, and high energy and power densities, the best among previously reported carbon material based gel-type symmetric supercapacitors. It also showed excellent mechanical stability under high angle bending and performed well in a wide temperature range. It is a promising candidate for next-generation supercapacitors, cost-effective, wearable, suitable for roll-to-roll mass production, and applicable in a wide temperature range.