Hierarchical FeO@C@MnO@C Multishell Nanocomposites for High Performance Lithium Ion Batteries and Catalysts.

The FeO@C@MnO@C (FCMC) nanocomposites containing spindle-like FeO as a core and MnO nanoflakes as a sandwiched shell and double carbon layers have been successfully prepared by a facile method. As anode materials of lithium ion batteries (LIBs), the cycling stability, rate performance, and conductivity of the prepared FCMC nanocomposites are far beyond those of the carbon-free FeO@MnO (FM) nanocomposites. The hierarchical structure with double layers of carbon effectively enhances the ion conductivity and electrochemical performance of transitional metal oxides, indicating that carbon in FCMC played an important role during lithium ion storage. The initial discharge/charge capacity of the FCMC electrode reaches as high as 1240.2/1215.9 mAh g, and the discharge capacity is over 1000 mAh g at 500 mA g after 50 cycles. Additionally, the unique hierarchical structural characteristic with double layers of green carbon with a high degree of graphitization makes FCMC an excellent catalyst in removing methylene blue (MB) dye from solution with HO under a slight heating with the degradation time as short as 10 min. Our work presents a new perspective on carbon modified multilayer core-shell oxide structure, which can be applied to many fields such as energy storage and catalyst.