Structural, magnetic, and magnetocaloric properties of Fe2CoAl Heusler nanoalloy

Abstract

Spherical nanoparticles (NPs) of size 14 nm, made of intermetallic Fe2CoAl (FCA) Heusler alloy, are synthesized via the co-precipitation and thermal deoxidization method. X-ray diffraction (XRD) and selected area electron diffraction (SAED) patterns confirm that the present nanoalloy is crystallized in A2-disordered cubic Heusler structure. Magnetic field (H) and temperature (T) dependent magnetization (M) results reveal that the NPs are soft ferromagnetic (FM) with high saturation magnetization (Ms) and Curie temperature (Tc). Fe2CoAl nanoalloy does not follow the Slater Pauling (SP) rule, possibly because of the disorder present in the system. We also investigate its magnetic phase transition (MPT) and magnetocaloric (MC) properties. The peak value of the magnetic entropy change vs T curve at a magnetic field change of 20 kOe corresponds to about 2.65 J/kg-K, and the observed value of refrigeration capacity (RCP) is as large as 44 J/kg, suggesting a large heat conversion in magnetic refrigeration cycle. The Arrott plot and the nature of the universal curve accomplish that the FM to paramagnetic (PM) phase transition in Fe2CoAl nanoalloy is of second-order. The present study suggests that the Fe2CoAl nanoscale system is proficient, useful and a good candidate for the spintronics application and opens up a window for further research on full-Heusler based magnetic refrigerants.

25 pages, 9 figures, 2 tables

References in corpus (8)

• Direct measurements of the magnetocaloric effect in pulsed magnetic fields: The example of the Heusler alloy Ni${}_{50}$Mn${}_{35}$In${}_{15}$
• Large magnetocrystalline anisotropy in tetragonally distorted Heuslers: a systematic study
• Size-Dependent Structural and Magnetic Properties of Disordered Co2FeAl Heusler Alloy Nanoparticles
• First-principles calculations and experimental studies on Co2FeGe Heusler alloy nanoparticles for spintronics applications
• Reversible adiabatic temperature change in the shape memory Heusler alloy Ni2.2Mn0.8Ga: An effect of structural compatibility
• Complex exchange mechanism driven ferromagnetism in half-metallic Heusler Co${}_2$TiGe: Evidence from critical behavior
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• Field dependent neutron diffraction study in Ni50Mn38Sb12 Heusler alloy

Cited by in corpus (3)

• First-principles calculations and experimental studies on Co2FeGe Heusler alloy nanoparticles for spintronics applications
• Intrinsic and extrinsic anomalous transport properties of Heusler ferromagnets Fe${}_2$CoAl and Fe${}_2$NiAl from first principles
• Terahertz magneto-optical response in ferromagnetic Fe-Co-Al alloys