(70at) Coating Metals on the Cenosphere by Magnetron Sputtering Method

Abstract Cenospheres are a sandlike component of the fly ash that is collected in coal-burning electric power generating plants. The density of the individual beads is 0.7-0.1 gcm-3 and their diameter range is 40-200 um. The shells consist primarily of a fused Si02 glass and mullite (3A12O3-2Si02). A newly designed equipment was used to coating different metals on the cenosphere surface. The major part of the equipment is the part that keeping the fine particles dispersing and threshing in the sputtering area to make each particle can get the same opportunity to be coated. The low density metals-coated cenosphere particles may be utilized for manufacturing conductive polymer for EMI shielding application, absorb electromagnetic wave material and high light reflected material, etc. It is show that this new type equipment can coat different metals on the cenosphere surface with the thickness from several nanometers to several micrometers and the surface is very smooth and the metal layer is very compacted. And the metal integrated tightly with the cenosphere surface. Extensive characterization of coated particles is carried out by scanning electron microscopy (SEM), X-ray diffraction(XRD), atom force microscopy(AFM) and Raman techniques to study the coating process and to show successful deposition of pure Ag, Cu, Ni, Al and Co.

Keyword : coating, cenosphere, magnetron sputter, metal coating, SEM, XRD