APCVD of thermochromic vanadium dioxide thin films—solid solutions V2–xMxO2 (M = Mo, Nb) or composites VO2 : SnO2

Abstract

Atmospheric pressure chemical vapour deposition of V 22x M x O 2 (M = Mo, Nb; X = 0.01-0.003) thin films was achieved on glass substrates from the reaction of VOCl 3 , H 2 O and MCl 5 . Comparable reactions with SnCl 4 formed SnO 2 : VO 2 composites. The ease with which solid solutions or composite films formed was related to the relative reaction rates. The films were characterised by X-ray diffraction, Raman, X-ray photoelectron spectroscopy and scanning electron microscopy. Doping of the VO 2 phase was shown to affect both the growth morphology and the thermochromic properties of the films. The Mo-doped VO 2 films showed a thermochromic switch of 47 uC with a narrow hysteresis (4-6 uC).

Synthesis and Functional Properties of Vanadium Oxides: V2O3, VO2, and V2O5 Deposited on Glass by Aerosol‐Assisted CVD

“…Vanadium(IV) oxide in the monoclinic form, VO 2 (M), shows a thermally induced, reversible, metal-tosemiconductor transition to the rutile form VO 2 at 68°C. [1] Both electrical and optical properties in the near infrared (IR) are remarkably affected by the transition; in fact VO 2 (M) behaves as a semiconductor and does not reflect much solar energy; VO 2 (R), on the other hand, behaves as a semimetal and reflects a much wider range of solar wavelength. [2] For this transition and for the associated property changes, VO 2 can be used as an intelligent window material.…”

Thin Films for Advanced Glazing Applications

“…Niobium has also been investigated, but it was found to be less effective than tungsten. The Tc of the films was typically decreased by 2 °C per at % doping [164], by 13 °C per 0.4% at [165] and by 15 °C per 2 at % Nb doping [166]. Other dopants explored include magnesium [167] and cerium [168] which decreased Tc by 3 °C and 4.5 °C, respectively per at % doping each.…”

Novel Chemical Vapour Deposition Routes to Nanocomposite Thin Films

“…Vanadium dioxide films were synthesised from the atmospheric pressure chemical vapour deposition reaction of vanadium oxychloride (VOCl 3 ) or vanadium tetrachloride (VCl 4 ) and water. The formation of a nanocomposite thin film was achieved by codeposition with another metal oxide precursor that reacted at a faster rate than the vanadium precursor, SnCl 4 and Ti(O i Pr) 4 were utilised for this purpose (Manning et al 2005). The titanium dioxide and vanadium dioxide nanocomposites were formed from the codeposition of VCl 4 and Ti(O i Pr) 4 at 650 °C.…”

“…Atmospheric pressure ahemical vapour deposition (APCVD) has been used to investigate the production of thermochromic nanocomposite thin films by Parkin et al in a series of papers investigating the dual deposition of VO 2 and TiO 2 or SnO 2 (Manning et al 2005;Qureshi et al 2006;Qureshi et al 2004). Vanadium dioxide films were synthesised from the atmospheric pressure chemical vapour deposition reaction of vanadium oxychloride (VOCl 3 ) or vanadium tetrachloride (VCl 4 ) and water.…”