Enhancement of Electrochemical Performance by the Oxygen Vacancies in Hematite as Anode Material for Lithium-Ion Batteries.

The application of hematite in lithium-ion batteries (LIBs) has been severely limited because of its poor cycling stability and rate performance. To solve this problem, hematite nanoparticles with oxygen vacancies have been rationally designed by a facile sol-gel method and a sequential carbon-thermic reduction process. Thanks to the existence of oxygen vacancies, the electrochemical performance of the as-obtained hematite nanoparticles is greatly enhancing. When used as the anode material in LIBs, it can deliver a reversible capacity of 1252 mAh g at 2 C after 400 cycles. Meanwhile, the as-obtained hematite nanoparticles also exhibit excellent rate performance as compared to its counterparts. This method not only provides a new approach for the development of hematite with enhanced electrochemical performance but also sheds new light on the synthesis of other kinds of metal oxides with oxygen vacancies.