Transition Metal (Mn, Ni) Co-doped CdO Nanoparticles: Demonstration of Structural, Optical, and Magnetic Properties

Pristine cadmium oxide (CdO) and manganese and nickel (Mn, Ni) co-doped CdO (Cd0.98-xMn0.02NixO, 0 <= x <= 0.07) nano-particles (NPs) were synthesized using co-precipitation method. The properties of synthesized nanoparticles were investigated in detail. X-ray diffraction (XRD) patterns illustrated the single cubic phase of CdO NPs. And its crystal structure remains unaffected with co-doping of Mn, Ni and no secondary phase has been observed. Fourier transform infrared (FTIR) spectra also confirmed that Mn, Ni ions substituted at the host cationic sites in cubic lattice of CdO without any impurity or secondary phase. The surface morphology of as-prepared NPs was examined using field emission scanning electron microscopy (FESEM) micrographs. Also, energy dispersive X-ray spectroscopy (EDX) was used to determine the elemental compositions and it confirmed the presence of all elements present in the synthesized NPs. In UV-Vis spectroscopy analysis, absorption spectra revealed the increase in optical band gap energy (determined from Tauc's plot) of CdO NPs with co-doping. Magnetic behavior was also examined and noticed that co-doping of Mn and Ni into CdO NPs enhanced the room temperature ferromagnetic ordering with increasing doping concentration.