The distribution of interstitial zinc in zinc oxide

Abstract

A method is described which enables the position of interstitial zinc within the crystals of zinc oxide powders to be determined. The crystals are etched to various depths with acid, and the excess zinc content of each fraction is estimated. It is shown that the distribution of the interstitial zinc is dependent upon the species of chemisorbed oxygen prevalent, and that a marked concentration of excess zinc in the surface fraction of the crystals is apparent only in those samples of zinc oxide on which the oxygen chemisorbed is predominantly of the reactive variety. The method provides a convenient means of following the diffusion of interstitial zinc on heating. The changes in the distribution of interstitial zinc in both types of zinc oxide that occur on heating in air are shown and discussed.