Size-dependent structural and magnetic properties of disordered Co2FeAl Heusler alloy nanoparticles

Abstract

Co2FeAl (CFA) nanoparticles (NPs) of different sizes were synthesized by chemical route. The effect of the size of NPs upon the structure and magnetization compared to its bulk counterpart was investigated. The structure and composition were determined from X-ray diffraction (XRD) and electron microscopy. XRD analysis shows that the samples are having single (A2-type) disordered phase. Magnetization measurements suggest that the samples are soft ferromagnetic in nature with very low coercivity. Enhanced magnetic properties like saturation magnetization, coercive force, retentivity, and Curie-temperature are observed with a decrease in particle size. The effect of particle size on hysteresis losses is also discussed. The smallest particles of size 16 nm exhibited the highest saturation magnetization and transition temperature of 180.73 emu/g and 1261 K, respectively. The origin of enhancement in magnetization of Co2FeAl nano-alloy is attributed to the strong Co-Co exchange interaction due to disorder present in the systems.

Atomic disorder and Berry phase driven anomalous Hall effect in Co2FeAl Heusler compound

“…The magnetic moment obtained from the magnetic isotherms (FIG. 2) is about 5.74 µ B /f.u and 5.50 µ B /f.u at 2 K and 300 K, respectively, which is close to the value reported in the literature [31,36,[47][48][49][50]. The variation of ρ xx as a function of temperature (FIG.…”

Structural and Magnetic Properties of Inverse-Heusler Mn2FeSi Alloy Powder Prepared by Ball Milling

“…In addition, the conventional techniques including arc and induction melting [10,11] producing the bulk materials, or dc-and rf-sputtering on different types of substrates in a form of thin films [12], there are still efforts for searching Heusler alloys with improved properties leading to involvement of non-traditional preparation technologies. Therefore, in last few years, there is couple of papers showing interesting properties of Heusler alloys prepared either by mechanical alloying (MA) in a form of powders [13,14] or by planar flow casting (PFC) technique having ribbon shapes [15,16]. The various ways of synthesis lead to structural imperfections on the atomic scale (antisite atoms, vacancies, etc.…”

Effect of Vd-doping on dielectric, magnetic and gas sensing properties of nickel ferrite nanoparticles

“…Vanadium has mixed valence states and it is located at octahedral and tetrahedral sites. Also, the vanadium increases accumulation of Fe 2+ ions that enforces transfer of Ni 2+ ions from desired octahedral site to tetrahedral sites [35][36][37][38]. In nutshell, this scenario increases magnetization [18].…”