Mesoporous Multi-Valence Manganese Oxides Composite Nanotubes Boosting Long-Life Lithium-Ion Batteries.

Multi-component nano-oxide composite materials may present special synergistic effects as anode materials for lithium-ion batteries. Mesoporous β-MnO2/Mn3O4 composite nanotubes are built here via controlling the deoxidation process of carbon-coating to induce a partial phase transition of high valence manganese dioxides. Compared to single β-MnO2 nanotubes or Mn3O4@C nanotubes, the mesoporous β-MnO2/Mn3O4@C composite nanotubes exhibit superior electrochemical properties. 679 mA h g-1 of reversible specific capacity and 86% of capacity retention after 1000 cycles at 1 A g-1 current density are obtained. The excellent performance is attributed to the unique multiple phase transitions regulation phenomena of manganese oxide occurring in the β-MnO2/Mn3O4 composite material during the electrochemical processes, which significantly extends the cycle life of the β-MnO2/Mn3O4 composite material.