Mass-dependent isotopic fractionation in electroplating investigated by SIMS

Osawa, Takahito  ; Esaka, Fumitaka  

Stable-isotope fractionation was observed in redox reaction of chromium in laboratory experiments. Electroplating process of transition elements is active redox reaction between liquid and solid phase and some degree of mass-dependent or independent isotopic fractionation is expected. In order to clarify the isotopic fractionation in electroplating, we analysed Ni and Cu isotopes on the surface of electroplates using Cameca ims-6f ion microprobe and determined fractionation factors. Electrodes and solution were completely homogenised in isotopes and thin coating on an electrode were done under various current and temperatures. 58Ni, 60Ni, and 62Ni were measured in Ni analysis, and 63Cu and 65Cu were measured in Cu analysis. We did not use any kind of spikes in this work. In contrast with a previous report by Kavner et al. (2005), we found no voltage-dependent fractionation.