Preparation of NiO/SiO2 Particles by Chemical Vapor Deposition

Attempts to prepare NiO/SiO specimens were successively performed by chemical vapor deposition (CVD). The starting materials were all gaseous components : nickel chloride (g), silicone tetrachloride (g) and oxygen. In this method, highly dispersed NiO in a SiO2 matrix is more easily prepared than by chemical fumed deposition (CFD), which was previously performed by the thermal decomposition of nickel chloride/methanol fume in atmosphere. In this report, in contrast to the CFD method, it is found that the CVD method could reduce the diameter of supported NiO on SiO from 205 nm to 38 nm whilst the degree of dispersion could remain unchanged during the increase of nickel content from 3.4% to 8.8 %. From the above facts, the CVD method is superior to other methods in that the nickel oxide particles were highly dispersed on the SiO2 matrix.