Study of pretreatment techniques and characterization of electroless silver on cenospheres

Electroless Ag-coating of cenosphere particles is demonstrated in the present investigation. The electroless Ag-coating process is modified by replacing the conventional pretreatment and sensitization steps by only using a surface hydroxylation step with NaOH hydroxylating agent to simplify the steps and reduce the overall cost of the coating process. Furthermore, the activation and electroless plating steps are merged into one step. The cenosphere particles are characterized by scanning electron microscope (SEM), energy dispersive x-ray spectroscopy (EDX), X-ray diffraction analysis (XRD), and fourier transform infrared (FT-IR) before and after the coating process. The relatively uniform and continuous coating is obtained under the given coating conditions. The possible mechanism of electroless Ag-coating of cenosphere particles utilizing surface hydroxylation of cenospheres is suggested.