An experimental and theoretical study of the optical, electronic, and magnetic properties of novel inverted α-Cr2O3@α-Mn0.35Cr1.65O2.94 core shell nanoparticles
Magnetic core-shell nanoparticles (CSNs) have potential applications in spintronic devices, drug delivery systems, and magnetic random access memory. By use of our hydrothermal nano-phase epitaxy method, we have accomplished synthesis of novel, well-ordered α-Cr2O3@α-Mn0.35Cr1.65O2.94 inverted CSNs. XRD and TEM analyses show a core-shell structure with corundum phase throughout the core and shell with a minimal amount of interface defects. TEM-EDX and XPS data show Mn having the +2 oxidation state in the shell of the CSNs. Magnetization measurements at 5 K show a weak coercivity (H C) value of 8 Oe and an exchange bias field (H E) of 293 Oe. Ab initio calculations show that Mn incorporation in α-Cr2O3 results in narrowing of the energy band gap, substantiated by UV-Vis measurements, and half metallic behavior in case of Mn(III) substitution. Our calculations substantiate that Mn substitution in α-Cr2O3 results in a combination of antiferromagnetic and weak ferrimagnetic character of our CSNs.
Physics, Astronomy, and Materials Science
core/shell, magnetic properties, nanostructure
Hossain, Mohammad D., Robert A. Mayanovic, Ridwan Sakidja, and Mourad Benamara. "An experimental and theoretical study of the optical, electronic, and magnetic properties of novel inverted α-Cr 2 O 3@ α-Mn 0.35 Cr 1.65 O 2.94 core shell nanoparticles." Journal of Materials Research 32, no. 2 (2017): 269-278.
Journal of Materials Research