Abstract
The formation process of Co, Ni, Co-Ni alloy nanoparticles by electroless deposition in nonaqueous solution (ethylene glycol: EG) was electrochemically investigated. When the solvent decomposes during the cathodic reduction of relatively-less noble metals (Co, Ni, Fe, etc.) , the reduction current of the metals is hardly measured from the total current by the voltammetry because of the large contribution of the decomposition of the solvent. In this work, the deposition current of Co and Ni was evaluated from a weight change due to the metal deposition on a quartz crystal microbalance electrode. The deposition current of Co on a Co substrate was much higher than that of Ni on a Ni substrate, and the oxidation current of a reducing agent (hydrazine monohydrate) on Co is also higher than on Ni. This resulted in a decrease of Co-Ni nanoparticle size by the addition of Ni.
