Hybrids of 2D-Nanomaterials for Supercapacitor/Battery Applications

Supercapacitors and batteries are energy storage systems, the former offering a high power density and a high degree of cyclability, and the latter being mainly a high energy density device.  Batteries and supercapacitors store energy electrochemically by interaction of an electrode material and an electrolyte. The energy stored is proportional to the surface area of the electrochemically active material and therefore high surface area 2D-nanomaterials are suitable for this application. In this work, we present the manufacture of thin-film supercapacitor/battery electrodes using cost-effective and scalable methods: solvent-exfoliation followed by spray deposition.  A variety of 2D-nanomaterials that can be grouped in two categories, carbon-based and metal oxides, were synthesized, characterized and evaluated.  We have exploited the concept of hybridization to combine the properties of two 2D materials in a "hybrid" synthesized by a single step liquid-phase exfoliation method. First synthesized metal oxide-graphene hybrids showed an improved charge storage capacity. This work constitutes the proof-of-concept work for future investigation on rational design of functional 2D hybrid nanomaterials.