Doped Nanostructured Manganese Ferrites: Synthesis, Characterization, and Magnetic Properties

Nanocrystalline aluminum-doped manganese ferrite was synthesized by facile thermal treatment method. Nanostructure-doped ferrite with crystalline size that ranged between 3.71 and 6.35 nm was characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and vibrating-sample magnetometry (VSM). The Scherrer and Williamson-Hall hypothesis techniques were utilized to determine lattice constants and strain. Various types of structural properties including octahedral and tetrahedral site radius, bond lengths and angles, hopping parameter, oxygen positional parameters, site bonds, and edge lengths were determined from XRD spectrum analysis. Discrepancy in the hypothetically expected angle indicates improvement of A-B superexchange intercommunication. Furthermore, magnetic-hysteresis (M-H) and XPS analysis support the claim of enhancement. The presence of the ionic nature of iron and manganese in ferrite is FeII, FeIII, MnII, and MnIV as revealed by the results of XPS. Moreover, XPS assists in an excellent way to understand the properties such as configuration, chemical nature, and average inversion degree of doped ferrite samples. The spin noncollinearity and exquisite interaction amid the sublattice are responsible for the decrease in the saturation and remnant magnetization determined from the hysteresis loop at ambient temperature with maximum magnetic field of 1.8 T.