Thermophoresis of metal particles in a liquid

Using a theory of phoresis of solid particles in a liquid, the thermophoresis of metal particles is theoretically examined. It is shown that, taking into account a transverse temperature distribution around a particle, significantly higher thermophoretic velocities of metal particles can be predicted than are possible according to current theory. The role of surface potential distribution is examined. The attractive electrostatic potential of a double layer and a surface potential with a secondary minimum are considered, and the thermophoretic velocities at large energies of interaction are analytically evaluated. A comparison of the thermophoretic velocities of equal-sized metal and ''normal'' particles shows that the differences can be small or large depending mainly on the shape of the potential energy curve. (C) 1995 Academic Press, Inc.