Electrooxidation of Mn(II) to MnO2 on graphite fibre electrodes

Electrooxidation of Mn²⁺ to MnO₂ on carbon felt and carbon cloth electrodes (C-materials) in a weak sulfuric acid electrolyte was investigated using stationary and rotating electrodes. These materials exhibit better performance than more conventional materials such as lead. Scanning electron micrographs of the deposits show a uniform cylindrical growth of MnO₂ encapsulating the carbon fibres. The deposits spontaneously fracture following straight-lines indicating a fibrous microstructure. X-ray diffraction reveals a -MnO₂ structure for all deposits.