The influence of gas phase composition on the process of Au–Hg amalgam formation

Interaction of thin Au films deposited on a glass substrate with Hg vapor at 298 K was studied. The influence of gas phase composition on the kinetics of the amalgamation process was examined. Several gas atmospheres were tried: vacuum (residual gases pressure ∼1×10−7 Pa, with Hg vapor pressure 0.24 Pa), H2, Ar and air at pressure around 101 kPa. The electrical resistance measurements in the process of Au–Hg amalgam formation were correlated with the atomic force microscopy investigations of amalgam surface structure and X-ray diffraction spectra of the bulk. The results of these studies clearly demonstrate the influence of gas phase composition on the kinetics of the amalgamation process. The experimental data are compared with theoretical calculations of the kinetic processes occurring at the thin Au film surface.