Preparation and dielectric property of Ag–PVA nano-composite

The property of nano-powder was reviewed with emphasis on its Coulomb blockade effects. Ag-colloid of different concentration with different particle size was prepared. Ag–PVA composite colloid was obtained by mixing Ag-colloid with PVA solution. TEM showed that Ag particles (<100 nm) were uniformly dispersed in PVA. The resistivity at room and low temperatures and breakdown field strength of samples were investigated. The results show that dielectric properties of composite change while Ag content or distributing state changes. The composite with 20–30 nm Ag particles has a higher resistivity and breakdown field than its matrix. In a word, Coulomb blockade effects of metal powders could improve resistivity and breakdown field of its matrix.