A simple wet-chemical approach to synthesize shape controlled high magnetic moment Fe71–Co29 nanocrystals

Spherical Fe71–Co29 nanocrystals functionalized by trisodium citrate (TSC) have been synthesized using co-precipitation process. The synthesized nanocrystals have disordered structure, reductive hydrogen annealing at 450 °C has transformed the disordered phase to body centered cubic phase (CsCl structure) without secondary phases which was subsequently authenticated using Rietveld refinement technique. The TSC adhere with the Fe–Co nanocrystal's surface by carboxylate chemisorption which has been confirmed using FT-IR spectroscopy. Back scattered electron microscope image confirms the spherical morphology with size around 20 nm. The observed saturation magnetization is as large as 95.6% of bulk (242 emu g−1) which is a significant indication for the crystallization of single phase Fe71–Co29 nanocrystals.

► Fe–Co nanocrystals free from secondary phases have been synthesized.
► Rietveld refinement authenticates the single phase of Fe–Co nanocrystals.
► BCC structure has been achieved by reductive H2 annealing at 450 °C.
► Ms of synthesized sample indicates the crystallization of Fe71–Co29 nanocrystals.