Direct formation of single crystal VO2(R) nanorods by one-step hydrothermal treatment

Pure phase VO2(R) nanorods were directly synthesized via the reduction of V2O5 by oxalic acid during one-step hydrothermal treatment. The products were characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectrom spectroscopy, FTIR and UV-vis spectroscopy. By adding a proper amount of H2SO4 as morphology control agent, monodispersed single crystal VO2(R) nanorods were obtained from the hydrothermal solution for the first time at relatively lower temperature (260 degrees C) and even shorter time (4 h). The prepared nanorods showed very excellent thermochromic property with narrower hysteresis and lower phase transformation temperature compared with bulk materials. (C) 2009 Elsevier B.V. All rights reserved.