Physicochemical, structural and induced ferromagnetic properties of Co-In-codoped CdO synthesised via Cd chloride: significant effect of post-treatment hydrogen

摘要

Nanoparticle solid solution powders of cadmium oxide doped with different concentrations of cobalt and indium ions were synthesised by solvothermal method through CdCl (2) ai... H (2) O precursor route. The objective of the present work is to study and develop conditions necessary to create stable room-temperature ferromagnets (RT-FMs) in transparent conducting oxide (TCO) CdO for applications in the field of dilute magnetic semiconductors (DMSs). To achieve this aim, cobalt (Co (2+) ) dopant ions were used as a source of stable FM, while In (3+) dopant ions supply free electrons that enhance the electronic medium of interaction. The electronic medium in the host CdO lattice, which carries the long-range spin-spin (S.S) exchange interaction between localised Co (2+) (3d) spins of dopant ions, was further developed by annealing in hydrogen gas (hydrogenation). The crystalline structure of the powder samples was investigated by the X-ray diffraction (XRD) method. The optical absorption properties were studied by diffuse reflection spectroscopy (DRS). Magnetic measurements reveal that the Co-In-codoped CdO powder has FM properties superimposed on paramagnetic (PM) behaviour. However, annealing in hydrogen atmosphere strongly boosts the created FM so that the saturation magnetisation increases similar to 90 times. Physical explanations and discussion are given in the article. Thus, it is proved that the magnetic properties could be tailored to TCO CdO by Co-doping and post-treatment under H (2) atmosphere.