Graphene is a material that is being widely explored for its potential applications notably in the field of energy (batteries, supercapacitor, fuel-cell catalyst…). Indeed it was described that graphene could be used as additive for the development of new negative electrodes for Li-ion batteries for example. In parallel, Si nanostructures (SiNSs) have been developed and tested in micro-supercapacitor cells and showed an amazing long cyclability (over millions of cycles) while the specific capacitance achieved could be improved.
The aim of this PhD project, conducted in collaboration between INAC/SyMMES and INAC/PHELIQS, is to develop methods to stabilize the Si nanostructures/electrolyte interface and to grow these Si NSs inside a graphene structured matrix to increase the surface area and thereby increase the capacitive properties of the micro-supercapacitor in terms of specific capacitance, power and energy densities. The growth of Si NSs inside a graphene matrix will also allow to decouple the NSs from a 2D substrate. Thus higher amount of material may be obtained, and supercapacitor rather than micro supercapacitor applications will be tested.