Defect Engineering in Titanium-Based Oxides for Electrochemical Energy Storage Devices

Defect engineering involves the manipulation of the type, concentration, mobility or spatial distribution of defects within crystalline structures and can play a pivotal role in transition metal oxides in terms of optimizing electronic structure, conductivity, surface properties and mass ion transport behaviors. And of the various transition metal oxides, titanium-based oxides have been keenly investigated due to their extensive application in electrochemical storage devices in which the atomic-scale modification of titanium-based oxides involving defect engineering has become increasingly sophisticated in recent years through the manipulation of the type, concentration, spatial distribution and mobility of defects. As a result, this review will present recent advancements in defect-engineered titanium-based oxides, including defect formation mechanisms, fabrication strategies, characterization techniques, density functional theory calculations and applications in energy conversion and storage devices. In addition, this review will highlight trends and challenges to guide the future research into more efficient electrochemical storage devices.Graphic AbstractThis work reviews the recent advances in defect-engineered Ti-based oxides, including the mechanism of defect formation, fabrication strategies, the characterization techniques, density functional theory calculations and the applications in energy conversion and storage.