Electroless Platinum Deposition Using Co3+/Co2+ Redox Couple as a Reducing Agent.

In the present work, the kinetics of electroless deposition of Pt, using a cobalt ion redox system (Co3+/Co2+) as a reducing agent, has been investigated. The deposition rate of Pt depends on the pH, concentration of reactants, and temperature. The deaeration and bubbling of the plating solution with argon play an essential role. It was found that 0.11 mg cm-2 of Pt films could be deposited on the surface of a roughed glass sheet in one hour without replenishing the solution. Additional data have been obtained on the grounds of electrochemical quartz crystal microbalance experiments. The bubbling (agitation) of the electroless Pt plating solution with argon during the deposition of Pt results in a higher deposition rate and is ca. 3 µg cm-2 min-1. The Pt deposition rate is far less, and is as low as 0.14 µg cm-2 min-1 when the electroless Pt plating solution is not bubbled with argon during the deposition of Pt.