Preparation Of The Composited Metal Oxide And Its Performance As Anode Material For Lithium-ion Batteries

Lithium-ion batteries(LIBs) with the advantages of high capacity, long cycling life, light weight, portablity, and environmental friendliness has become one of the promising power sources as the portable electronic devices. The performance of the LIBs is rely heavily on the ability of the anode electrodes, consequently the design and fabrication of highly efficient anode materials are of great significance to both academic researches and industrial applications. Graphite as the commercial anode material for LIBs has the relatively low theoretical capacity, which hampers the implementation its applications. Metal oxide anode materials with the superiority of high theoretical capacity have attracted great attention in recent years. However, the poor electrical conductivity and large volume change during charge/discharge process limit its further development. In order to compensate for these shortcomings, one of the effective strategies is to hybridize with other metal oxides that possess larger theoretical capacities to construct the metal oxide composites. In addition, the fabrication of nanostructured materials have been proposed as another method to modify their low conductivity. In this work, the composited metal oxide nanomaterials are easily fabricated via the dealloying stratergy. The prepared composited metal oxide nanomaterials show excellent electrochemical performance as anode materials for LIBs.The main contents of this paper:1. Refining the MnFeAl, Mn Co Al, and TiCo Al ternary alloys with uniform and controllability components. By etching the Al atoms in Na OH solution for the certain time, the remained atoms undergo the direct oxidization to form the Mn3O4/Fe3O4 nanoflowers, MnCoOx spiny microspheres, and porous TiO2/Co3O4 composite.2. Characterizing the structures and the compositions of prepared Mn3O4/Fe3O4 nanoflowers, MnCoOx microspheres, and nanoporous TiO2/Co3O4 composited oxides. It shows that the as-made Mn3O4/Fe3O4 consists of a packed array of uniform regular hexagon-like nanoslices with interconnected voids. MnCoOx microspheres are built by the second-order interlaced nanosheets. The uniform nanoporous structure are formed in TiO2/Co3O4. In addition, the three composited metal oxides are produced with control and uniform compositions through characterizing the structure of prepared materials by XRD, EDS, and XPS analysis.3. Characterizing the electrochemical performance of prepared Mn3O4/Fe3O4 nanoflowers, MnCoOx spiny microspheres, and nanoporous TiO2/Co3O4 composited oxides materials. The flower-like Mn3O4/Fe3O4 composite delivers a specific capacity of 1040.3 m A h g-1 at a current density of 300 m A g-1 after 200 cycles. Mn CoOx spiny microspheres delivered a specific capacity after 450 and 500 cycles at a current density of 300 mA g-1 and 1000 mA g-1. TiO2/Co3O4 composite achieves the enhancements in the capacity compared with the TiO2 at the low and high rates. The TiO2/Co3O4 composite also exhibits satisfactory cycling stability for 500 cycles and excellent rate capability as anode material for LIBs. With the advantages of outstanding performance and easy preparation, the prepared composite manifests great application potential as anode material for LIBs.