The microemulsion method for preparing ZnO nanocrystallites was reported.Through measuring ZnO microcrystllite ESR spectra, we found that at room temperature it has a significant ESR signal and its intensity descends with the increase of annealed temperature. This result is incontrast with that of bulk ZnO which is a diamagnetic material and no ESR signal. Finally it was found and verified that on the surfaces of ZnO nanocrystallites there are a lot of oxygen vacancies and defects which trap electrons and form paramagnetic centers to provide the observed ESR signal.
展开▼
