Zn excess in ZnO is built up automatically at high temperatures. Excess Zn in hydrothermally grown ZnO is investigated by the atomic absorption photometry (AAP) method. To determine the excess zinc in ZnO samples, the AAP of zinc vapour was used in the conditions of solid-vapour equilibrium. Optical absorbance of zinc, proportional to the concentration of zinc atoms in the vapour phase, was registered photoelectrically on the Zn resonance line. Zn AAP allowes to eliminate excess Zn connected differentially in ZnO samples. To fix Zn non-stoichiometry, all the ZnO samples tested were previously heat treated at temperature interval from 850 to 900⁰C and at fixed Zn vapour pressures from 0,1 to 0,9 of saturated zinc vapour pressure at given treatment temperature. Our AAP investigations in polycrystalline ZnS and ZnSe showed that the analytically determined concentration of Zn excess appears to be bigger than the concentration of electrically active defects. Zn adsorption on crystallite surfaces must be taken into account in ZnO also. The analysis of temperature dependence of zinc vapour pressure indicated that the value of zinc excess lies in the concentration interval of 10¹⁸ - 10¹⁹ cm^-3 and depends on the sample biography and the conditions of preliminary heat treatment. Impurity metals take active role in the determination of non-stoichiometric zinc. The experimental results were used for preliminary high temperature defect equilibrium calculations for ZnO.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/2290 must be provided.

1. High temperature defect equilibrium in ZnS:Cu single crystals
2. Pretreatment of cellulose matrix for the generation of one-dimensional nanostructures
3. High temperature electrical conductivity in ZnSe:In and in CdSe:In under selenium vapor pressure