METHOD FOR INHIBITING THE OXIDATION OF VO(ACAC)2 IN SOLUTION

摘要

The present invention provides a method to effectively inhibit the oxidization of VO(acac)₂ in solution for months. It is believed that VO(acac)₂ forms a π-complex with as many as three allylic alcohols which precludes reaction with any oxygen in the system. Although saturated and homo-allylic alcohols were also tested, this effect appears only in the allylic-alcohol based solutions. This ability to inhibit oxidation of VO(acac)₂ allows these solutions to be used for making thermochromic VO₂ film much more easily and economically as it avoids the requirement of operating under low oxygen level conditions. Thus the present invention provides a method of stabilizing vanadium oxyacetylacetonate (VO(acac)₂) in solution against oxidation for extended periods of time, comprising the steps of mixing the oxyacetylacetonate precursor in an allylic alcohol prior to spin-coating for VO₂ film formation. The allylic alcohol may be (β-methallyl alcohol. Alternatively, the allylic alcohol may be any one of 4-buten-2-ol, 2-buten-1-ol, 1-penten-3-ol, 2-hexen-1-ol and 1-hexen-3-ol.