Ag-TiO₂ Nanometer Complex-phase Ultrafines Prepared by Liquid Arc discharge and Its Optical Properties

It is reported firstly that Ag-TiO₂ hybrid ultrafines is prepared by liquid arc discharge combined with hydrothermal treatment. According to XRD and TEM analysis the phase of product obtained may be rutile phase or anatase phase with narrow she distribution in the range of 5~30nm. TEM image of hybrid particles obtained from the complex-phase ultrafines by ultrasonic dispersion shows that some Ag and TiO₂ particles closely link together to form a calabash - like nanostructure. A surface - enhanccd Raman scattering （SERS） of Ag-TiO₂composite decorated by Ag particles is also observed, although the magnitude of enhancement is not as large as that of the colloidal particles system coated by metal on the surface. We also briefly discuss the possibility of forming nanometer-scale structure model of （TiO₂ nuclei with coating Ag）-pure TiO₂ complex phase particles.