Strong physisorption and superb thermal stability of carbon nanofibers carried Cu^sub x^O-V^sub 2^O^sub 5^ enabling the flexible and long-cycling supercapacitor

Carbon nanofibers supported the vanadium and copper bimetallic oxide composite electrode material has been developed successfully in this study, as the outstanding electrode materials in supercapacitors. In electrospunning and calcination processes, the organic salt of vanadium underwent high temperature decomposition to form V2O5 in situ. The various ratios of CuxO-V2O5/CNFs composite electrode material were used to apply in the electrochemical performance testing through the vacuum impregnation method. Because of the copper doping, CuxO-V2O5/CNFs (10:1) composites exhibited a specific capacitance of 867.2 F g−1 at 0.5 A g−1 over a potential range of 0–0.51 V, which surpassed those of their individual counterparts (682.5 F g−1 and 507.1 F g−1 at 0.5 A g−1 for V2O5/CNFs and CuCl2/CNF, respectively). The addition of trace copper oxide greatly improves the electrochemical performance of vanadium-based carbon fibers composites. The composites also showed good cycling stability due to the unique structure of the V2O5 and synergies with copper oxide. The preparation route provided a novel strategy to synthesize composites of transition bimetallic oxide with improving electrochemical performance for applications in supercapacitors.