Influence of surface properties of ceramic particles on their incorporation into cobalt electroless deposits

The purpose of this work was to elucidate factors affecting electroless codeposition of metal with ceramic particles. Codeposition of various particles with Co-P in an alkaline solution was compared. Powders of SiC, Al2O3 and SiO2 were used. It was found that surface properties of the technical powders were different from that reported for materials of high purity. Codeposition of SiC was favored by a positive surface charge of the particles, while negative surface charges of alumina and silica inhibited their embedding. The positive surface charge of SiC particles corresponded to low adsorption of cobalt ions and increased adsorption of hypophosphite anions, while opposite dependencies for alumina and silica were observed.