Abstract
We report the crystal structure and magnetic properties ofZn1−xCoxO (0≤x≤0.10) nanoparticles synthesized by heating metal acetates in organic solvent. The nanoparticleswere crystallized in the wurtzite ZnO structure after annealing in air and in a forming gas(Ar95% + H5%). The x-ray diffraction and x-ray photoemission spectroscopy(XPS) data for different Co content show clear evidence for theCo2+ ions in tetrahedral symmetry, indicating the substitution ofCo2+ in the ZnO lattice.However, samples with x = 0.08 and higher cobalt content also indicate the presence of Co metal clusters.Only those samples annealed in the reducing atmosphere of the forming gas,that showed the presence of oxygen vacancies, exhibited ferromagnetism at roomtemperature. The air annealed samples remained non-magnetic down to 77 K.The essential ingredient in achieving room temperature ferromagnetism in theseZn1−xCoxO nanoparticles was found to be the presence of additional carriers generated by the presenceof the oxygen vacancies.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.