1. Electrodeposition of Magnetic SmCo 5 Alloy Films from Aqueous Solution Chengkun Xu, Morton Schwartz, and Ken Nobe* Department of Chemical and Biomolecular Engineering University of California, Los Angeles, CA 90095, USA
2. Excellent magnetic properties of SmCo 5 Coercivities: ~100 Oe; 40 kOe upon annealing Current fabrication: vacuum deposition processes; high cost. Electrodeposition: simpler, more versatile, and less expensive. Objective: obtain SmCo deposit with Sm content > 16.7at%
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5. Cell geometrical arrangement 1 (CGA-1) Cell geometrical arrangement 2 (CGA-2) Effect of current distribution CD up to 400 mA/cm 2 can be used. Sm: 8.3 at% Non-uniform current distribution Uniform current distribution Cathode
6. 01/13/11 Effects of pH and glycine concentration Co 2+ + Gly 1- = [CoGly] 1+ lgK=4.57 Co 2+ + 2Gly 1- = CoGly 2 lgK=8.28 Co 2+ + 3Gly 1- =[CoGly 3 ] 1- lgK=10.8 Sm 3+ + Gly 1- = [SmGly] 2+ lgK=3.5 High pH results in less vigorous H 2 evolution. Thus CE increases, leading to the increase in partial CD for Sm deposition. As glycine/cobalt reaches 3, Co complexes is the most stable, leading to the lowest free Co concentration, thus the highest Sm content.
7. Effects of low Co concentration and glycine/cobalt Glycine/cobalt ratio must be kept at 3 The SmCo deposits were amorphous.
