Magnetic and Structural Characterizations of Co-based Heusler Nanoparticles Fabricated via Simple Co-precipitation Method

Abstract

Nanoparticles of Co 2 FeAl magnetic alloy was successfully fabricated in the presence of a well-known capping agent, polyvinyl alcohol, as a polymer template. The magnetic properties were studied using hysteresis curve and firstorder reversal curve (FORC) measurements at room temperature. FORC diagrams demonstrated a wide distribution of the coercive field owing to the presence of different particle sizes in products. TEM image also showed that the synthesized samples are composed of some large clusters containing a few smaller particles. The maximum value of magnetization (*76 emu/g) and coercivity (573 Oe) were obtained in the annealed sample with 5°C/min. A wider distribution of grain size with a smaller average of 20.5 nm as well as lower-degree of crystallinity was observed in the sample annealed with higher rate of 10°C/min.

Size-dependent properties of single domain Fe2CoGa nanoparticles prepared by a facile template-less chemical route

“…8 and 9. Pezeshki-Nejad et al 52 and Alikhanzadeh-Arani et al 53 showed that for Co 2 FeAl nanoparticles, a decrement in size results in decrement in M s which is in agreement with our observations. The decrement in the M s with decrement in crystallite size can be interpreted using the core-shell model for nanoparticles, which divides the nanoparticle of size d into a ferromagnetic core and magnetically dead layer (or shell) of thickness t on its surface, 54 i.e.,…”

Influence of the surfactant and annealing rate on the morphology, magnetic and structural characteristics of Co2FeAl nanoparticles

“…(full-Heusler) or XYZ (half-Heusler), where X and Y are usually transition elements such as Ni, Co, Fe, Pd, Cr, and Z is an sp element such as Si, Al, Ge [1][2][3]. So far, several reports on the use of half-metallic Cobased full-Heusler alloy electrodes in magnetic tunnel junctions have been presented [4], synthesizing by different techniques, including conventional dc sputtering [5], ion beam sputtering [6], low-temperature molecular beam epitaxy [7], electrodeposition [8], arc melting method [9,10] and melt-spinning process [11].…”