Densely packed graphene nanomesh-carbon nanotube hybrid film for ultra-high volumetric performance supercapacitors

Densely packed graphene nanomesh-carbon nanotube hybrid (GNCN) film was prepared through a simple graphene etching process and subsequent vacuum-assisted filtration method. Based on its high surface area, fast ion diffusion and high film density, the GNCN film electrode shows ultra-high volumetric capacitance of 331 F cm−3 at 5 mV s−1 in 6 M KOH, which is among the highest values for graphene film reported in aqueous electrolyte, as well as excellent rate capability and outstanding cycling performance.491