Taloring solid state electrodes for the development of next generation asymmetric supercapacitors

Abstract

Hybrid asymmetric supercapacitors are able to realize high energy and power density. It not only provides energy sustainability to reduce the environmental pollutions, but also promises ideal future as next generation energy storage devices. The electrodes of hybrid asymmetric supercapacitors utilize carbon based electrodes including activated carbon (ACs), Carbon Nanotubes, graphene and graphene oxide. Other electrode materials include transition metal compounds based electrodes including oxides, hydroxides, sulfides, nitrides, phosphides. Conductive polymers are classified as another important materials of high performance electrodes. However, some of the them may show sluggish ion transfer or diminished electrochemical stabilities due to a variety of redox reaction mechanisms. and their unique crystallographic features. Thus it is rather important to study the manipulation and enhancement of electrochemical charge storage processes of such pseudocapacitive materials. This article analyzes the use of each electrode materials, further discusses research that has been spent efforts on to solve their intrinsic drawback. The review is hopefully to provide an illustrative prospective on the preparations and fabrications of the next generation hybrid asymmetric supercapacitors.