Hybrid Graphene Titanium Nanocomposites and Their Applications in Energy Storage Devices: a Review

Emissions of natural gas and carbon dioxide due to fossil fuels have become a global issue which influences the development of various technologies. Demand for clean renewable power sources is ever increasing. However, renewable sources are intermittent in nature, which poses a challenge in electricity generation and power load stability. Lately, supercapacitors have attracted remarkable interest in the field of electricity storage due to their ability to store large amounts of electric charge, enabling high power output. Reduced graphene oxide incorporated with titanium dioxide (rGO/TiO2) nanocomposites are well considered as potential supercapattery materials due to their superior mechanical properties, notable strength, and abundance in Nature. rGO carbon material acts as the ion reservoir, facilitating faster electron transfer mobility, whereas mesoporous TiO2 provides a larger surface area and more active sites, which improve the cycling stability and specific capacitance. Literature reports that supercapacitor performance mainly depends on the choice of the electroactive material, electrolyte, and current collector. This review focuses on recent developments in supercapacitor technology, storage mechanisms of different electrodes, a comprehensive discussion of different challenges related to energy storage devices, as well as the formation mechanism of rGO/TiO2 hybrid electrodes.