Magnetic Property of Sm-Co Nanoparticles Prepared by Solution Phase Metal Salt Reduction
Sm-Co magnetic nanoparticles were successfully synthesized at high temperature above 680 degrees C in solution phase. The chemical composition was determined by EDX and it was found that the composition of as-synthesized Sm-Co magnetic nanoparticles showed less Sm content compared with the composition of starting materials. From TEM and FE-SEM measurements, the morphology of as-synthesized and heat-treated Sm-Co a magnetic nanoparticle was confirmed as hexagon and apatite crystal structure. Curie temperature was observed at around 680 degrees C correspond to SmCo5 phase. The magnetic property was measured by VSM and shows the ferromagnetic characteristics.
Available from: Saravanan Padmanapan
[Show abstract] [Hide abstract]
ABSTRACT: Thin magnetic films of Sm–Co nanocrystallites on SiO2 substrate were fabricated using spin coating deposition. In a typical synthesis, precursor of Sm–Co oleate complex was spin coated onto a SiO2 substrate in the form of precursor films and subsequently they were subjected to reductive annealing at 773 K for 2 h, so as to crystallize Sm–Co phase in the films. It has been found that the reductive annealing temperature (573–773 K) played a critical role on the nucleation and formation of Sm–Co crystalline phases; while the spinning speed (3000–5000 rpm) has a significant effect in controlling the film thickness, which in turn affects the particle diameter, inter-particle distance and packing density of the Sm–Co nanocrystallites. Coercivity values of 27.9, 23.9 and 18.7 kA⋅m− 1 and magnetization values of 2.89, 2.51 and 2.21 × 10− 6 A⋅m2 were achieved for the Sm–Co films with thicknesses of 345 (3000 rpm), 264 (4000 rpm) and 162 nm (5000 rpm), respectively. Further, these hard magnetic properties could be significantly improved by subjecting the Sm–Co films to post-annealing at 873 K.
[Show abstract] [Hide abstract]
ABSTRACT: Pulsed IR laser irradiation of SmCo5 alloy in vacuum and in adjacent dielectric breakdown (DB) of benzene has been examined as a tool for modifying phase and composition of this alloy and for suitability to serve as a laser deposition technique of Sm–Co nanoparticles and Sm–Co/C films. The composition of solid deposits was determined by FTIR, X-ray photoelectron and Raman spectroscopy and electron microscopy, and gas-phase chemical changes upon irradiation in gaseous benzene were analyzed by gas chromatography and FTIR and GC/MS spectroscopy. IR laser ablation in vacuum leads to deposition of amorphous Sm1.00Co2.1–2.2 films containing uniformly dispersed Co2Sm5 nanocrystals and to formation of residual Sm2Co17 target phase, both of which indicating disproportionation of SmCo5 and Sm-enrichment of ablated particles. IR laser ablation in benzene results in formation of ultrafine powders consisting in fully amorphous Sm1.00Co4.2–4.6 nanoparticles embedded in amorphous hydrogenated carbonaceous phase and is in keeping with minor structural changes in ablated SmCo5 particles. Both deposited materials are shown to differ in magnetic properties and the carbonaceous shell serves as a protection of Sm–Co nanobodies towards atmospheric oxidation.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.