Condensation of gold vapour on silicone oil – effect of the liquid substrate

Abstract

When gold vapour condenses onto a liquid substrate, the inherent structure of the liquid could influence the condensate growth and coverage. A thorough comparison between the liquid (silicone oil) and solid (amorphous carbon) substrates is reported by analysing the changes in their condensate growth. Low condensate coverage with large areas of empty regions is observed on the liquid surface in contrast to the solid carbon surface displaying uniformly distributed gold clusters at all times. This is deduced to be caused by the incoming gold atoms restricting the liquid molecules’ degrees of freedom upon binding. This effect could perturb the entire liquid structure, causing the liquid to collectively act against the adsorption of gold atoms. This could lead to differences in growth kinetics on the liquid substrate and can account for the observed dissimilarity in condensate coverage. The substrate structure effect discussed here serves as a step forward for utilizing liquid substrates for a variety of potential applications.

Keywords:

• liquid surface
• deposition
• nucleation and growth kinetics

Acknowledgements

The authors wish to acknowledge the Facility for Analysis, Characterization, Testing and Simulation (FACTS) in Nanyang Technological University, Singapore, where the electron microscopy work was performed.