Effect of polar surface on the growth of Au

Abstract

The growth of Au on faceted MgO(111) and MgO(100) films was investigated by Auger electron spectroscopy, low energy electron diffraction, scanning electron microscopy, atomic force microscopy, and Raman spectroscopy. On the polar MgO(111) surface, a continuous Au film is easily formed because of the large surface energy compared with MgO(100). Heating the Au films grown on MgO(111) results in the formation of nanoparticles of Au. A relatively high Raman activity of the Au nanoparticles is observed. The size of Au nanoparticles might be adjusted by controlling the density of facets on (111) through changing the thickness of the polar oxide films. Our results provide a new insight into the preparation of nanoparticles of metals by choosing a polar surface as a patterned substrate, which may also be applied to other metal/oxide systems.