Characterization of niobium and vanadium oxide nanocomposites with improved rate performance and cycling stability

Highlights: • Niobium and vanadium oxides nanocomposites were synthesized using a facile sol–gel process. • Such nanocomposites exhibit both significantly improved rate and cycling stability. • Possible synergistic mechanism between the constituent components of the nanocomposites was proposed. -- Abstract: Niobium and vanadium oxides nanocomposites are synthesized using a facile sol–gel process, and characterized by scanning and transmission electron microscopy. X-ray diffraction results show that the nanocomposites are composed of Nb2O5 and its solid solutions. Such nanocomposites exhibit both significantly improved rate and cycling stability. At a current density of 1 A g−1, the nanocomposites deliver more than three times of capacity than pure Nb2O5, and remain ∼95% of its initial capacity after 50 cycles. Possible synergistic mechanism between the constituent components of the nanocomposites is also proposed