Electron spectroscopy imaging and surface defect configuration of zinc oxide nanostructures under different annealing ambient

▸ Electron spectroscopy imaging revealed non stoichiometry of elemental distribution in ZnO nanopowder. ▸ Oxygen annealing increased the ratio of O:Zn distribution while nitrogen annealing gave an adverse effect. ▸ Oxygen and nitrogen annealing provided different effects to the surface conductivity of ZnO pellets. ▸ Oxygen vacancies were identified as major defect in the annealing process. ▸ Different stress levels were obtained from different morphologies of ZnO.