Electron microscopy of size distribution and growth of small zinc crystals formed by homogeneous nucleation in a flowing inerthyphen;gas system

摘要

Homogeneous nucleation of small Zn particles has been observed in a flowing inerthyphen;gas system. Zn vapor was produced by heating the bulk metal near 700 K in flowing N2at pressures near 15 Torr. Nucleation of small Zn particles took place in a cooler region downstream from the furnace. Cooling occurred by gas conduction to roomhyphen;temperature walls. Particle sizes measured by electron microscopy were from 5 to 5000 nm. Samples were obtained with varying metal temperature, gas flow rate, pressure, and position in the collection chamber. Particles grew with time and had a predominant shape characterized as a regular hexagonal prism.