A study of the correlation between hydrogen content and magnetism in ZnCoO

Through the hydrogen treatment of Co-doped ZnO (ZnCoO), the Co-H-Co complex manifests the magnetization mediated by H. The increase in hydrogen content causes an increase in the number of Co-H-Co units, which can be controlled by the hydrogen treatment conditions. The 15 mol. % ZnCoO showed a proportional tendency between the hydrogen content and remnant magnetization under different conditions of rf power for the plasma treatment. The 20 mol. % sample showed deviation from the proportional tendency by the existing CoO phase before hydrogen injection and the formation of the Co metal phase after hydrogen injection. If one ensures the enhanced solubility limit of Co in ZnO and uses the correlation between the hydrogen content and magnetization below the solubility limit, this magnetic tool may be a good method for the measurement of the hydrogen content. (C) 2012 American Institute of Physics. [doi:10.1063/1.3671786]