Method of Preparing Vanadium Dioxide Nanoparticles

The following conclusions are made concerning unsupported VO2 syntheses presented here: • Controlling the concentration of NH3(aq) catalyst in the inverse micelle reaction of VO(OiPr)3 is not adequate for (1) reducing premature precipitation from inverse micelles, (2) minimizing agglomeration of particles, or (3) controlling the reduction of V(V) precursors for the preparation of VO2 nanoparticles. • The onset of turbidity in the inverse micelle reaction of a VO(OiPr)3/oleic acid premix is prolonged by decreasing the concentration of NH3(aq) catalyst. • The inverse micelle reaction of a VO(OiPr)3/oleic acid premix results in premature precipitation of product from inverse micelles leading to particle agglomeration. • Thermal treatment in H2(g) in the inverse micelle reaction of VO(OiPr)3/oleic acid premix contributes to V2O3 contamination of VO2 samples. • The use of a VO(OiPr)3/acetic acid premix in an inverse micelle reaction facilitates the formation of monodispersed, spheroidal-shaped VO2 nanoparticles. • Thermal treatment of 10%H2/90%N2(g), used in the inverse micelle reaction of VO(OiPr)3/acetic acid premix, reduces V2O3 contamination of VO2 samples. • Thermal treatment of as-prepared powders dispersed on a silicon wafer reduces particle sintering and supports monodispersity of formed particles without agglomeration.