2D Film of Carbon Nanofibers Elastically Astricted MnO Microparticles: A Flexible Binder-Free Anode for Highly Reversible Lithium Ion Storage.

Abstract

MnO as anode materials has received particular interest owing to its high specific capacity, abundant resources, and low cost. However, serious problems related to the large volume change (>170%) during the lithiation/delithiation processes still results in poor rate capability and fast capacity decay. With homogenous crystals of MnO grown in the network of carbon nanofibers (CNF), binding effect of CNF can effectively weaken the volume change of MnO during cycles. In this work, a CNF/MnO flexible electrode for lithium-ion batteries is designed and synthesized. The CNF play the roles of conductive channel and elastically astricting MnO particles during lithiation/delithiation. CNF/MnO as binder-free anode delivers specific capacity of 983.8 mAh g-1 after 100th cycle at a current density of 0.2 A g-1 , and 600 mAh g-1 at 1 A g-1 which are much better than those of pure MnO and pure CNF. The ex-situ morphologies clearly show the relative volume change of MnO/CNF as anode under various discharging and charging times. CNF can elastically buffer the volume change of MnO during charging/discharging cycles. A facile and scalable approach for synthesizing a novel flexible binder-free anode of CNF/MnO for potential application in highly reversible lithium storage devices is presented.