Enhancing saturation magnetization of Mg ferrite nanoparticles for better magnetic recoverable photocatalyst

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2018-12, Vol.124 (12), p.1-9, Article 844
• Main Authors: Mostafa, Nasser Y., Zaki, Z., Hessien, M. M., Shaltout, A. A., Alsawat, M.
• Format: Article
• Language: English
• Subjects: Applied physics; Characterization and Evaluation of Materials; Condensed Matter Physics; Crystallites; Electron recombination; Low level; Machines; Magnesium ferrites; Magnetic properties; Magnetic saturation; Magnetization; Manufacturing; Materials science; Microstrain; Molybdenum; Nanoparticles; Nanotechnology; Optical and Electronic Materials; Photocatalysis; Physics; Physics and Astronomy; Processes; Substitutes; Surfaces and Interfaces; Thin Films
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-018-2268-z

Simple combustion route was implemented for the preparation of Mo-substituted magnesium ferrite nanoparticles; MgFe 2−2 x Mo x O 4 ( x  = 0.0, 0.1, 0.2 and 0.3). Samples, with x  = 0.0, 0.1 and 0.2, revealed only the cubic spinel ferrite phase. Sample with x  = 0.3 showed very small amount of FeMoO 4 , beside MgFe 2 O 4 . The lattice parameter diminished with increasing molybdenum contents to x  = 0.1, then increased at x  ≥ 0.2. The saturation magnetization ( M s ) increased from 15.65 to 32.05 emu/g with low level of Mo 6+ substitution ( x  = 0.1), then declined with x  > 0.1. This is the first investigation to report M s of Mg ferrite nanoparticles higher than its bulk value. The change in magnetic properties is correlated with cation distribution between tetrahedral sites (A) and octahedral sites (B). Mo 6+ replaced the Fe 3+ position in the tetrahedral A-sites for x  = 0.1. In samples with x  ≥ 0.2, Mo 6+ occupied both A-sites and B-sites. Mo substitution decreased the crystallite size and increased the microstrain. Mo substitution in MgFe 2 O 4 enhanced the photocatalytic action compared to bare MgFe 2 O 4 . The enhancement was due to the increase in structure defect that inhibits the electrons–holes recombination as well as the increase in surface area.