Three dimensional N-doped graphene–CNT networks for supercapacitor

3D N-doped graphene-CNT networks (NGCs) can be obtained by hydrothermal treatment, freeze-drying and subsequent carbonization of graphene oxide-dispersed pristine CNTs in the presence of pyrrole. The resulting NCGs used as a supercapacitor show high specific capacitance, good rate capability and still retain ∼96% of the initial capacitance even after 3000 cycles.