A comparison of two methods for metallizing fly-ash cenosphere particles: electroless plating and magnetron sputtering

A dense and uniform metal layer was completely coated on the surface of fly-ash cenosphere particles by either electroless plating or magnetron sputtering technique. The surface morphology and characteristics of the electroless and sputtered metal coatings have been compared and investigated by various characterization methods, including scanning electron microscopy, energy dispersion x-ray spectrum, x-ray photoelectron spectroscopy, optical microscopy and atomic force microscopy. The results indicate that the electroless plating process has a faster deposition rate as compared with the sputtering process, and the metal coating fabricated by electroless plating is rough as compared with the metal coating fabricated by magnetron sputtering. The Cu-coated fine cenospheres could be fabricated by the electroless plating technique.