Journal of the Electrochemical Society, Vol.141, No.8, 1998-2003, 1994
Studies on Deposition and Dissolution Processes of Pbo2 in Perchloric-Acid Electrolytes
Electrochemical deposition and dissolution processes of PbO2 layers have been studied in 1M HClO4 solutions to investigate the effects of deposition potentials on the characteristics of the deposited layers. The results obtained from cyclic voltammetric, chronoamperometric, and chronopotentiometric experiments on the rotating ring-disk electrode indicate that the oxide layers have different electrochemical behavior when deposited at different potentials. The results are explained in terms of the nonstoichiometric nature of PbO2. Results of spectroelectrochemical experiments indicate that PbO is produced as a long-lived intermediate species during the reduction of PbO2. A reduction mechanism is proposed based on the relationship between the peak currents and potentials observed at the ring electrode while the PbO2 layer is reductively stripped at the disk electrode.
Keywords:OXYGEN-TRANSFER REACTIONS;LEAD DIOXIDE ELECTRODE;SULFURIC-ACID;BEHAVIOR;ELECTROCATALYSIS;REDUCTION;BETA-PBO2;GOLD