3D net carbon-based cobalt sulfides for high-performance supercapacitors by a simple, green and convenient method

•CoS2\C composites were synthesized by paper template method.•CoS2\C composites exhibited a high specific capacitance of 1320.3 F g−1 at current density 1 A g−1.•The 3D network structure reduces the crushing and dissolution of metal sulfide particles. Transition metal sulfides have attracted widespread interest in energy storage devices due to their unique functions. Here, a simple, green and convenient process has been developed to produce CoS2-decorated 3D carbon network CoS2/C materials. The simple electrode materials of CoS2/C for supercapacitors with the natural carbon network structure provided by filter paper showed multiple advantages, such as accessible high specific surface area, high specific capacitance, and the improved conductivity. The significantly improved specific capacitance of 1320F g−1 at 1A g−1 and excellent rate capability with an ultrahigh capacitance retention of 80.9% at 10 A g−1 were obtained. Cycle performance of the capacitance retention rate is 72.5% after 1000 charge and discharge cycles were retained.