Preparation and characterization of silver coated magnetic microspheres prepared by a modified electroless plating process

Abstract Silver-coated Fe microspheres were fabricated by the modified electroless plating process without the pretreatment and sensitization steps. Surface modification step with TiO2 shells provides a continuous and full coverage of Ag shells on Fe microspheres. Ethylene diamine and ammonia were used as a complexing agent to form silver shells during the electroless plating process. Their reflectance was investigated to understand the role of the surface morphology of the silver shells on their optical properties. The growth of the Ag shells at the early stage of the reaction was investigated. Structure and optical properties of the resulting silver-coated Fe microspheres were evaluated based on scanning electron microscopy, silver shell thickness, reflectance and crystal structure analysis. The silver shells prepared with ethylene diamine were more homogenous and compact than those with ammonia.