Study of the character of gold nanoparticles deposited onto sputtered cerium oxide layers by deposition-precipitation method: Influence of the preparation parameters

Abstract

Au/CeOx/Si system was prepared by a combination of physical and chemical methods for application in the heterogeneous catalysis. Gold nanoparticles were loaded by the deposition-precipitation method (HAuCl4∙4H2O used as a precursor) onto radio frequency magnetron sputtered layers of cerium oxide. The study focuses on the influence of the experimental parameters (pH of the solution, time of immersion) on the nature of gold deposit. After the preparation process, the samples were characterised by electron microscopy and X-ray photoelectron spectroscopy methods. The amount of gold loaded and its morphological parameters are discussed. We show that gold particles with high density and the mean diameter of around 4 nm are deposited from the solution with pH 7. In the case of higher value of pH, the uptake of gold significantly decreases and particles with slightly bigger mean diameter are deposited onto the substrate.