Vanadium dioxide and gold nanocomposite films for glazing application

Vanadium dioxide is a material with great potential as an intelligent glazing material. The technology is based on a metal to semiconductor transition (MST) where there is an associated structural change from the higher temperature rutile structure to the lower temperature monoclinic structure. This structural transition results in significant changes in optical properties and electrical conductivity. Hybrid aerosol assisted and atmospheric pressure chemical vapour deposition methodology has been utilised, to produce thin films of gold nano-particle vanadium dioxide nanocomposites. Good surface coverage is observed comparable to that of APCVD processes and a variety of different film thickness’s and dopant levels have been made easily. The addition of tetraoctyl ammonium bromide (TOAB) to the precursor solution gave control of the size of vanadium oxide crystallites and led to an enhancement of thermochromic properties. Films were analysed by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. Their optical and thermochromic behaviour was also determined. Incorporation of gold nano-particles in the films leads to significant changes in the colour of the film due to the presence of a surface plasmon resonance band.