High energy density supercapacitors composed of nickel cobalt oxide nanosheets on nanoporous carbon nanoarchitectures

Abstract

Porous carbon–metal oxide hybrid materials are advanced functional composites with great potential for use in high energy density supercapacitors. Here we describe a hybrid structure composed of two-dimensional (2D) NiCo₂O₄ nanosheets synthesized on polyhedral-shaped nanoporous carbon (NC) particles. The NC particles were derived from the carbonization of zeolitic imidazole frameworks (ZIF-8). Supercapacitor devices assembled using NiCo₂O₄-NC nanoparticles had excellent capacitive properties with energy densities up to 28 W h kg⁻¹ and power densities up to 8.5 kW kg⁻¹.