Thermodynamics and Adsorption Behaviour of the Nano Phases in the Bi-Sn System

Abstract

The study of thermodynamic behaviour of the surfaces based on the derivative technique is shown to be significantly different from that of the bulk phase of the system. Nano particle binary alloy phase diagrams have been evaluated from the information on the Gibbs free energy of mixing and surface tension of the alloys using the combined form of Butler's and the Thomson-Freundlich equations. The evaluated phase diagram for the nano phases in the Bi-Sn system is found to be considerably different from the constitutional phase relations for the alloys of the planar surface. The melting temperatures of the components decrease considerably with decrease in the size of the nano particle. The reduction in melting points of the components accompanies with a decrease in the eutectic temperature of the system. The mutual solubilities of the terminal nano phases increase considerably resulting in restriction of the two phase field with consequent increase in the area of the liquid phase in the system. The deviation of the behaviour of the nano phase increases as the size of the nano particle decreases. The drop of the eutectic temperature is found to reach a minimum for 1 Nm particle. The adsorption studies of the nano phases establishes a pronounced increase in the adsorption function which increases with decrease in the size of the nano particle.