Deposition of Three-Dimensional Graphene Aerogel on Nickel Foam as a Binder-Free Supercapacitor Electrode

Abstract

We reported a new type of graphene aerogel–nickel foam (GA@NF) hybrid material prepared through a facile two-step approach and explored its energy storage application as a binder-free supercapacitor electrode. By simple freeze-drying and the subsequent thermal annealing of graphene oxide hydrogel–NF hybrid precursor, three-dimensional graphene aerogels with high mass, hierarchical porosity, and high conductivity were deposited on a NF framework. The resulting binder-free GA@NF electrode exhibited satisfactory double-layer capacitive behavior with high rate capability, good electrochemical cyclic stability, and a high specific capacitance of 366 F g^–1 at a current density of 2 A g^–1. The versatility of this approach was further verified by the successful preparation of 3D graphene/carbon nanotube hybrid aerogel–NF as a supercapacitor electrode, also with improved electrochemical performance. With advantageous features, such a facile and versatile fabrication technique shows great promise in the preparation of various types of carbon–metal hybrid electrodes