Effect of Nucleation and Growth Dynamics on Saturation Magnetization of Chemically Synthesized Fe Nanoparticles

Abstract

In order to obtain mono-dispersed Fe NPs with high saturation magnetization, quantitative analysis method to investigate the growth dynamics of the Fe NPs synthesized by a conventional thermal decomposition method has been developed. As a result, fast nucleation process promotes formation of ~4 nm of initial nucleus with a non-equilibrium phase, resulting in low saturation magnetization. And slow particle growth with atomic-scaled surface precipitation mode (< 100 atoms/(min·nm 2 )) can form the growth layer on the surface of initial nucleus with high saturation magnetization (~190 emu/g Fe ) as an equilibrium a phase of Fe. Therefore, higher stabilization of small initial nucleus generated just after the injection of Fe(CO) 5 should be one of the key issues to achieve much higher M s of Fe NPs.

Direct Synthesis of Single Crystalline $\alpha$-Fe Nanoparticles With High Saturation Magnetization by Mixed Surfactant

“…Phase volume was estimated by Rietveld analysis (reliability factor , Goodness of fit [11]. Residual amount of Fe(CO) in reaction solution was estimated by Fourier-transform infrared spectroscopy (FT-IR) [5].…”

Core loss and magnetic susceptibility of superparamagnetic Fe nanoparticle assembly

“…A chemical synthesis method was employed to synthesize Fe NPs with a small NP size distribution. [9][10][11][12] Fe NPs with 4.3 nm and 6.4 nm in average diameter were synthesized by the modified thermal decomposition of a Fe(CO) 5 oleylamine reacted precursor. (see further details in Ref.…”