Carbonaceous and Hydrogenated Nanostructured Materials for Energy Storage Devices

Abstract

Materials engineering and nano-manipulation play a key role in the development of advanced Lithium-ion batteries (LIBs) in terms of energy and power density (both gravimetric and volumetric), stability, rate capability, safety and the cost of production. In this thesis, two strategies are used to address the demands, i.e., the use of low cost and environmentally benign carbonaceous nanostructured materials (CNMs) and the use of hydrogenation technology. In the first strategy, CNMs including carbon nanotubes (CNTs) and graphene are incorporated with anode materials (such as metal oxide and carbon) to synthesize corresponding CNM composites that possess improved electrochemical performance because it can not only provide highly conductive matrix but also prevent the aggregation of the nanostructured electrode materials and the CNMs. TiO2-reduced graphene oxide (TiO2-RGO) was prepared for LIBs using photocatalysis method. TiO2 nanoparticles can be anchored on the GO sheets via the abundant oxygen-containing functional groups. Using the TiO2 photocatalyst, the GO was photocatalytically reduced under UV illumination, leading to the production of TiO2-RGO nanocomposite. The resultant LIBs of the TiO2-RGO nanocomposite possess more stable cyclic performances, larger reversible capacities, and better rate capability, compared with those of the pure TiO2 and TiO2-GO samples.