Publication Type : Journal Article
Publisher : Elsevier
Source : Powder Technology 2015, 274, 98–104. https://doi.org/10.1016/j.powtec.2015.01.002.
Url : https://www.sciencedirect.com/science/article/abs/pii/S0032591015000121
Campus : Amritapuri
School : School for Sustainable Futures
Year : 2015
Abstract : In this study, the composition, morphology and magnetic properties of Ni/NiO nanocomposites synthesized by hydrothermal-assisted polyol process were studied as a function of annealing temperature. Upon increasing the annealing temperature from 300 to 500 °C, the concentration of NiO was found to increase at the expense of metallic Ni-core and a complete transformation of NiO was evidenced at 500 °C. All the Ni/NiO nanocomposites demonstrated strong exchange bias (EB); however, the mechanism of the EB effect seems to be different in each case. For the samples annealed at low temperatures: 300 and 400 °C, the EB effect arises from the coupling at the Ni/NiO interface; whereas for the samples annealed above 400 °C, the EB effect is due to the coupling between frozen magnetic moments of NiO-shell and typical antiferromagnetic NiO-core. Enhancement in the EB and large coercivity were obtained for the sample annealed at 500 °C. Through this study, it has been demonstrated that the EB effect in the Ni/NiO nanocomposites can be tuned by controlling the composition and particle size of both ferromagnetic (Ni) and antiferromagnetic (NiO) components.
Cite this Research Publication : Gokul, B.; Saravanan, P.; Vinod, V. T. P.; Černík, M.; Sathyamoorthy, R. "Synthesis of Ni/NiO Nanocomposites by Hydrothermal-Assisted Polyol Process and Their Magnetic Properties as a Function of Annealing Temperature". Powder Technology 2015, 274, 98–104. https://doi.org/10.1016/j.powtec.2015.01.002.