Conversion of porous PbO2 layers through galvanic displacement reaction with Mn2 + ions

- The preparation of a porous oxide electrode via galvanic displacement is demonstrated.
- Porous PbO2 was electrodeposited and then reacted with Mn2 + acid solutions.
- A galvanic displacement reaction led to PbO2 reduction and deposition of a Mn oxide.
- The amorphous Mn oxide formed a shell onto porous PbO2, maintaining its morphology.
- The galvanic exchange reaction enhanced the capacity of the electrodes.

The galvanic exchange between Mn2 + ions and electrodeposited porous PbO2 was studied to produce a porous oxide whose lower conductivity prevented its direct oxygen bubble-templated anodic deposition. Immersion of PbO2 layers in acid acetate solutions of Mn2 + led to the formation of amorphous MnOx shell onto PbO2. Due to its amorphous nature, MnOx could not be proved to be MnO2 by XRD. However, MnOx was cathodically stripped at the same potential as MnO2. The deposition of the MnOx shell onto PbO2 enhanced the capacity of the porous electrodes.