"Nanostructured Electrodes for High Performance Supercapacitors "
Materials Science & Engineering, King Abdullah University of Science & Technology,
Thuwal, Saudi Arabia
Supercapacitors are electrochemical energy storage devices that fill the gap between batteries and electrostatic capacitors. They offer a combination of good energy storage and power densities. The focus of this talk will be on supercapacitors that combine nanostructured oxides with different forms of carbon, the traditional electrode material in double layer electrochemical capacitors, in the active electrode material of supercapacitors. Specifically we discuss graphene nanosheet-metal oxide binary and ternary composites and evaluate their effectiveness as supercapacitor electrode materials. The mechanism by which these oxides enhance the energy density of graphene nanosheets is discussed and shown to a combination of the so-called spacer effect and conventional redox reactions that are a characteristic feature of these metal oxides. Finally, electrodeposition of nanostructured oxides on carbon-coated three dimensional electrodes is shown to be a promising approach to improve supercapacitor performance.