Research On Electrodeposition Of Samarium-Cobalt Alloy Films In Reline Ionic Liquid And Their Properties

Because of their excellent magnetic properties Sm-Co alloy thinfilms could be widely used in the fields of magnetic recording,micro-motor. Electrodepositon is expected to substitute the presentpreparing methods such as sputtering for its simpleness. But the standardelectrode potential of Sm is so negative that it is difficult toelectrodeposite it in aqueous system. The special physical and chemicalproperties of ionic liquids make it a good electrodeposition solvent.Therefore Sm-Co alloy thin film was electrodeposited in ionic liquid.SmCo alloy thin films were electrodeposited in Reline ionic liquidformed with choline chloride and urea. The ionic in the ionic liquid couldcomplex with Co2+, which promoted the codeposition of Samarium andCobalt. Sm-Co alloy thin films of different compositions were preparedusing potentiostatic electrodeposition on copper. By changing thedeposition time, the composition of solution and the potential differentkinds of deposition were synthesized. When the content of Samarium ishigh the deposition is amorphous. The coercivity and the saturationmagnetizationof the deposited layer reduced when the content ofsamarium increased.The Sm-Co alloy nanowires deposited using AAO template are3-4microns long and have diameter about100nm. The nanowires havemagnetic anisotropy, and the anisotropy increased with the prolongation of the deposition time. When the deposition time was30mins theanisotropy of nanowires disappeared. Thin films of Sm-Co alloy wereelectrodeposited on the polished surface of crystal plane <111> in siliconsingle crystal which was doped by phosphorus. The alloys were crystal.The coercivity increased when the deposition potential decreased.The amorphous structure crystallized while it was annealed. Thedepositions on the copper were influenced by diffusion. When thetemperature of annealing was between600and700℃high coercivityappeared. When the temperature was high the coercivity decreasedbecause of diffusion. Pices of the deposition on the silicon single crystalwere chipped off after annealing and which made the coercivity decrease.