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 gamma-MnO2 structure for all deposits.