【Research Background】

With the rapid growth of application requirements for small electronic devices and electric vehicles, existing commercial anodes (graphite) have been difficult to meet the high energy density and weight specific power requirements of future lithium ion batteries (LIBs). In this case, silicon with a higher theoretical capacity (4200 mA hg -1), a lower lithiation potential (<0.5 V vs Li / Li +), and rich crust reserves is considered to be the most potential for LIBs Anode material. However, the main problem that hinders the large-scale and efficient application of silicon anodes is the volume expansion and contraction (> 300%) during the lithium formation process, which leads to severe structural fragmentation, resulting in rapid capacity loss, poor cycle stability, and poor rate characteristics . In addition, the conductivity of silicon is lower than that of graphite, resulting in greater irreversibility during the intercalation of lithium ions (de), which further reduces the initial coulombic efficiency.

【Achievement Introduction】

Recently, the team of Professor Yang Jianping of the Fiber Materials Modification Laboratory of Donghua University published the title in the internationally renowned academic journal  ACS Applied Materials & Interface : Interface-Amorphized Ti 3 C 2 @ Si / SiOx @ TiO 2   Anodes with Sandwiched Structures and Stable Lithium Storage research paper.

【Graphic introduction】

Figure 1. Schematic diagram of the formation process of Ti 3 C 2 @ Si / SiOx @ TiO 2 .

Figure 2. Electron microscope image and element distribution diagram.

Figure 3. XRD, pore size and XPS characterization analysis.

Figure 4. The corresponding electrochemical test.

Figure 5. Reaction kinetic analysis of lithium ion storage.

【Summary of this article】

The interface-amorphous Ti 3 C 2 @ Si / SiOx @ TiO 2 composite material with sandwich structure was successfully designed and prepared by MRR method , and the selected samples were coated with amorphous titanium dioxide by sol-gel method. Compared with Ti 3 C 2 @ Si / SiOx, Ti 3 C 2 @ Si / SiOx @ TiO 2 anode showed better performance in the first 10 cycles, with better cycle stability and better capacity Maintain ability.

Literature link:

DOI: 10.1021 / acsami.0c05116

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