Recent progress on transition metal oxides as advanced materials for energy conversion and storage

To meet the rapid advance of electronic devices and electric vehicles, great efforts have been devoted to developing clean energy conversion and storage systems, such as hydrogen production devices, supercapacitors, secondary ion battery, etc. Especially, transition metal oxides (TMOs) have been reported as viable electrocatalysts and electrode materials, owing to the advantages of high electrochemical activity, low cost, environmental friendly, safety and reliability. It has been shown that the modification method, e.g. morphology controlling, defect engineering and material composite, can optimize the electrochemical performance of TMOs. Here, an overview is presented on recent research advances in developing TMOs for energy conversion and storage systems, as well as some key challenges and perspectives in this promising field for the future are also proposed.