Beltlike V2O3@C Core–Shell‐Structured Composite: Design, Preparation, Characterization, Phase Transition, and Improvement of Electrochemical Properties of V2O3

A beltlike V2O3@C core–shell‐structured composite was successfully synthesized by thermal treatment with the precursor V3O7·H2O@C composite under an inert atmosphere. The phase, composition, structure, and morphology of the as‐obtained samples were confirmed by XRD, elemental analysis, FTIR, energy‐dispersive X‐ray spectroscopy (EDS), X‐ray photoelectron spectroscopy (XPS), IR Raman, SEM, and TEM measurements. The process of the formation of V2O3@C is briefly discussed. The carbon coated onto the surface of V2O3 is disordered, and V2O3 keeps the original morphology of V3O7·H2O. V2O3@C has an average length that ranges from 0.4 to 5.2 μm, a width of about 80–170 nm, and an average thickness of the shells of about 15.6 nm. The possible formation mechanism of V2O3@C is proposed as follows: the reaction undergoes a solid‐state reaction by the interface reaction between V3O7 cores and carbon shells. It was found that the V2O3@C composite possesses the same phase‐transition properties as V2O3, which could expand the possible applications of materials related to V2O3 in the future. Furthermore, a V2O3 sphere, a V2O3 nanobelt, and the beltlike V2O3@C composite were explored as cathode materials for application in lithium‐ion batteries. The beltlike V2O3@C composite electrode exhibited the best electrochemical properties among them, thereby achieving our aim of improving the electrochemical properties of V2O3.