Chemically synthesized magnetic Co–Fe–Ga alloy nanoparticles. (9th November 2016)

• Record Type: Journal Article
• Authors: Imai, Takatomo; Shima, Mutsuhiro
• Is Part Of: Japanese journal of applied physics. Volume 56:Number 1(2017)Supplement
• Publication Date: 2016-11-09
• Subjects: Physics -- Periodicals; 621.05
• DOI: 10.7567/JJAP.56.01AE04
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: Magnetic properties of Co2 Fe x Ga y alloy nanoparticles in the L21 ordered phase produced by chemical synthesis and post annealing have been investigated. Structural analyses of the Co2 Fe x Ga y samples by X-ray diffraction show that both ordered B2 and L21 phases are formed when Ga composition is in the range 0.66 ≤ y ≤ 1.42. With increasing y from 0.58 to 1.4 at x = 1.0, the coercivity increases from 7.1 to 23 mT, while the saturation magnetization decreases from 970 to 410 kA/m. Microstructural analyses using TEM reveal that the alloy particles annealed at 973 K are agglomerated by sintering. When Al(NO3 )3 was added during the synthesis, the average particle size significantly decreases from 84 to 12 nm, presumably due to the formation of aluminum oxides, resulting in the decrease in coercivity from 29 to 5.1 mT.