ABSTRACT
The twenty-first century demand for the rapid development of energy storage systems has led to the emergence of nanostructured materials into the scientific community. Transition metal oxides and dichalcogenides offer a vital role as active materials in supercapacitor application facilitated by their numerous distinct features. Defect engineered inorganic metal oxides, and metal chalcogenides show enhanced specific capacitance, excellent stability, and high energy density for supercapacitor applications. The examples of metal oxides include titanium dioxide, manganese dioxide, cobalt oxide, and other binary metal oxides. Metal chalcogenides family include molybdenum disulfide, tungsten disulfide, vanadium sulfide, tin sulphide. The widely explored strategies for defect engineering in these types of metal oxides and sulfides are the electrochemical method, hydrogenation, vacuum calcination, and plasma treatment. There is an interplay of defects and an associated formation of variable oxidation states of transition metal ions that help to increase in specific surface area, enhance electronic conduction, and provides less resistance to for ion diffusion for active redox reactions.
