Synthesis and magnetic properties of flower-like FeCo particles through a one pot polyol process.

FeCo alloys of various compositions with flower-like morphology were synthesized using a unique one pot polyol process. The morphology of Fe particles was cubic, whereas the FeCo particles showed flower-like morphology, with more petals for the Co rich FeCo. The average particle size varied from 120 to 155 nm depending on the composition of the alloy. The Curie temperature as determined by thermomagnetic analysis was 985°C for Fe67Co33 and 939°C for the Fe36Co64 samples. Their corresponding bcc to fcc phase transformation temperatures were 985 and 825°C, respectively. Coercivity up to 511Oe was observed due to the shape anisotropy arising out of the flower-like morphology compared to the usual cubic or spherical morphologies. Post-annealing studies showed that Fe67Co33 is more stable compared to other compositions.