Porous carbon nanofibers loaded with manganese oxide particles: Formation mechanism and electrochemical performance as energy-storage materials

Mn oxide-loaded porous carbon nanofibers are prepared by electrospinning polyacrylonitrile nanofibers containing different amounts of Mn(CH3COO)(2), followed by thermal treatments in different environments. It is found that the manganese salt may transform into gamma-Mn(OOH)(2) or other Mn compounds during the thermal oxidation in air environment, while further thermal treatment in argon atmosphere results in MnO and Mn3O4 particles confined to a nanoporous carbon structure. Surface morphology, thermal properties and crystal structures are characterized using various analytical techniques to provide insight into the formation mechanism of the porous structure. These Mn oxide-loaded porous carbon composite nanofibers exhibit high reversible capacity, improved cycling performance, and elevated rate capability even at high current rates when used as anodes for rechargeable lithium-ion batteries without adding any polymer binder or electronic conductor.