Recrystallization of Single-Crystalline VO2 Microtube Arrays on V2O5 Substrate

Single-crystalline VO2 microtube arrays on V2O5 substrate were fabricated through a thermal oxidation route based on resistive heating V foil in air. Four sheets of as-fabricated single-crystalline VO2 microtube arrays on V2O5 substrate were then, respectively, heated to approximately 855 °C and 1660 °C to melt V2O5 or VO2. Thereafter, the melted V2O5 or VO2 was cooled rapidly or slowly to recrystallize the liquid V2O5 or VO2. The morphologies and phases of the recrystallization products were characterized by scanning electron microscopy and X-ray diffraction. This study proposes that the peak temperature of heating and the cooling rate are responsible for the recrystallization products of single-crystalline VO2 microtube arrays on V2O5 substrate.