A study of Fe-B and Fe-Co-B alloy particles produced by reduction with borohydride

Abstract

Fe-B and Fe-CO-B alloy particles have been prepared by reduction of metal ions in aqueous solution by use of KBHl and NaBH4. It is shown that the boron content in the particles can be varied by changing the concentration of borohydride and the Fe/Co ratio. For the lowest boron concentrations a mixture of crystalline and amorphous alloysis formed. For higher boron concentrations all the material is amorphous.

Preparation and magnetic properties of amorphous Co-Fe-B nanoparticles

“…The saturation magnetization changed slightly same with formation with increasing of [NaBH 4 ]. This value is considerably lower than other amorphous nanoparticle (about 200 Oe [7,8,10]). This may be because of isolated amorphous nanoparticle form coated with PVP, from the XRD pattern and TEM images of this sample (shown in Figure 3).…”

“…Therefore, the size of powders must be decreased in nanometer size with monodisperse form to avoid eddy current loss. On the other hand, chemical reduction methods give a possibility to obtain the alloys in the form of nanoparticles with a wide range of compositions [6][7][8][9][10]. The chemical reduction method involves the addition of a reductor (usually NaBH 4 or KBH 4 ) into metallic salt aqueous solution, resulting in the precipitation of nanometer scale metallic particles.…”

Size distribution of FeNiB nanoparticles

“…[7] Ni(NO 3 ) 2 and Fe(NO 3 ) 3 were dissolved in ethanol and reducing agent KBH 4 was dissolved in water. Immediate addition of 50 ml ethanol containing 0.1 ml tetraetoxysilan to part of the thus obtained material gave FeNiB particles which are coated with the SiO 2 shell.…”

Influence of the borohydride concentration on the composition of the amorphous Fe–B alloy produced by chemical reduction of synthetic, nano-sized iron oxide particles

“…A novel synthesis route involving the formation of fine metal and metal-boride particles via sodium borohydride (NaBH 4 ) reduction of metal ions in aqueous solution has been successfully applied [3]. This development has opened a wealth of new possibilities for various applications of amorphous (TM-B) alloys such as ferrofluids, catalysts and recording media [4][5][6][7].…”