Electrochimica Acta, Vol.42, No.5, 887-891, 1997
Kinetics of Electroreduction of Glycinate Complexes of Palladium(II) on the Dropping Mercury-Electrode
The process of chelate complex Pd(gly)(2) electroreduction on the dme in weakly acidic solutions of NaF and NaClO4 (LiClO4) includes a slow electrochemical step without a preceding chemical step and has the diffusion limiting current. A similar mechanism takes place in alkaline solutions but with participation of palladium(II) complexes of different nature; this is evident from changes in diffusion coefficient and the parameters of electrochemical kinetics. The most probable complex composition for alkaline solutions is Pd(gly)(4)(2-) with glycinate ions coordinated monodentately only through nitrogen atom. Kinetic parameters of the electrochemical step (Tafel slope, rate constant) are given far both pH regions and the mechanism of the electrode process is discussed.
Keywords:ACID