Synthesis and characterization of belt-like VO2(B)@carbon and V2O3@carbon core-shell structured composites

VO2(B) nanobelts encapsulated into carbon core-shell structured composite (VO2(B)@C) was successfully synthesized using VO2(B) nanobelts as the cores and glucose as the shells via an environmental hydrothermal method. The adsorption carbonization growth (ACG) mechanism was proposed to explain the formation of VO2(B)@C. The influence of synthetic parameters, such as, the reaction temperature, concentration of glucose and reaction time, was systematically investigated to control the fabrication of VO2(B)@C. Subsequently, belt-like V2O3@C core-shell structured composite was prepared by the heating treatment of VO2(B)@C. Furthermore, the electrochemical properties of this novel belt-like V2O3@C core-shell structured composite was studied, indicating that it exhibits an initial discharge capacity of as high as 162 mAh/g and the discharge capacity is still 104, 89, 67 mAh/g after 30, 50, and 89 cycles, which is much higher than pure V2O3. The phase transition properties of V2O3 powder and V2O3@C composite were investigated by DSC, which revealed that V2O3@C has the same phase transition properties of V2O3. The as-obtained V2O3@C composite has potential applications to the cathode and functional positive temperature coefficient (PTC) materials. (C) 2011 Elsevier B.V. All rights reserved.