Thermodynamic Studies on Selected Metal Nanoparticles and Binary Alloys Systems at Bulk and Nanoscale

Abstract

Different theoratical, empirical and thermodynamic models have been employed to calcualte melting temperature reduction of the grain size particles. Melting temperature depression (MPD) for the nanoparticles has been calculated using different melting models and compared with the values reported in the literature such as: Liquid drop model, Surface phonon instability model, Gibbs Thomson equation, and Semi-empirical model etc. Nanoparticles have large surface to volume ratio and surface energy of nanoparticles display depletion in melting temperature. Experimental values of melting point depression for Al, Zn and Pb have been found to be in accordance with calculated values using Gibbs Thomson equation, Surface phonon instability model and liquid drop model respectively but for Si, Ag and Au it is significantly different. The effect of the shapes on melting point during the depression of nanoparticles has also been calculated for different shapes like thin film, icosahedron, wire, spherical, hexahedron, octahedron and tetrahedron of Al, Si, Ag, Au and Pb nanoparticles. newline