Bioinspired Architectures and Heteroatom Doping To Construct Metal-Oxide-Based Anode for High-Performance Lithium-Ion Batteries

The pursuit of increased energy density and longer lifespan lithium-ion batteries (LIBs) is urgently needed to satisfy a dramatically increased demand in the energy market. Currently, metal-oxide-based anodes are being intensively studied due to their higher capacities over current graphite anodes. This work introduces a sustainable strategy to construct a metal-oxide-based anode with high capacity and an extremely long lifecycle, in which the features of bioinspired architectures and heteroatom doping can contribute greatly to increased performances. In detail, 1D tubelike metal oxide (e.g., MnO) coated on an N-doped carbon framework (i.e. MnO/N-C) has been designed by using the naturally abundant and renewable Metaplexis japonica fibers (MJFs) as the biotemplate and heteroatom source. Benefiting from the uniqueness of structure and compositions, as-prepared MnO/N-C demonstrates extremely high rate capacities of 951, 777, 497, and 435 mAh g(-1) at the rates of 0.5, 2, 4, and 5 Ag-1, respectively, with a good stability of more than 1000 cycles. It was found that the electrochemical performances are superior to most previous MnO-based anodes, in which the faster kinetics of conversion due to the advantage of the ion/electron transportation and morphological evolution has been verified. It is hoped that the concept of bioinspired architectures with heteroatom doping can be applied in wider applications for increased capability.