【Research Background】                     

The design and development of advanced electrode materials for high-performance rechargeable batteries have been extensively studied. Very importantly, two-dimensional (2D) nanomaterials have become a very promising material system, thanks to their unique physical and chemical properties. Especially MXenes and phosphoene, which have higher conductivity and ion storage capacity, have received continuous attention. Recently, Professors Chunxian Guo and Chang Ming Li of Suzhou University of Science and Technology published a review article entitled " Recent Advances of Two-Dimensional (2D) MXenes and Phosphorene for High-Performance Rechargeable Batteries" in the internationally renowned academic journal ChemSusChem , which summarizes 2D MXenes The research progress of phosphine as electrode material, its physicochemical properties, including structure and electronic properties, as well as band gap and phosphene anisotropy. Second, the synthesis methods of the two materials and their applications in batteries, such as lithium ion batteries (LIBs), sodium ion batteries (SIBs), potassium ion batteries (PIBs), lithium sulfur batteries (Li-S batteries) and metals -Air battery. At the same time, they also analyzed the mechanism of performance improvement, as well as future challenges and opportunities.

【Graphic introduction】

Figure 1.  Electromagnetic wave spectrum, band gap range and corresponding frequency range of different types of two-dimensional materials.

Figure 2.  Synthesis process and electrochemical performance of Sn ⁴⁺ modified Ti 3 C 2 nanocomposite.

Figure 3.  Synthesis process of isopropylamine intercalated Nb 2 CT x and corresponding electrochemical performance.

Figure 4.  Synthesis of MXene / CNF complex.

Figure 5. The stability of Ti 3 C 2 by compounding with carbon materials ; the synthesis process of MoS 2 @ Ti 3 C 2 .

Figure 6. The electrochemical properties of the three phosphorus allotropes and black phosphorus.

FIG. 7. The M ⁺ - C-of Ti . 3 C 2 T X by using the synthetic scheme flocculation MOH (M ⁺ = of Li ⁺ , of Na ⁺ , K ⁺ , of TBA ⁺ ) and the microstructure schematic characterization.

Figure 8. The Ti-OH bond on the surface of MXene is replaced by S-Ti-C through heat treatment or polysulfide contact

Figure 9. Analysis of  CNT-MXene nanostructures and their application to lithium-sulfur batteries.

Figure 10.  Theoretical specific energy, volumetric energy density and voltage for different metal-air batteries .

Figure 11.  Schematic diagram of TiO 2 C @ CN x nanosheet synthesis and electrocatalytic performance.

【Summary and Outlook】

Although MXenes and phosphoene have made great progress as electrode materials for batteries, there are still some challenges that limit their further applications.

For MXenes, despite having good mechanical stability, high electronic conductivity and a relatively large specific surface area and other advantages, but its inherent relatively low capacity hindered its further development. Therefore, idealized electrode designs, such as creating micropores or nanopores on the surface of MXenes and compounding other redox materials, can be used to increase capacity. Another challenge is that, as of now, it is still difficult to prepare high-quality MXene using the first-used method . It is very important to improve the current etching stripping method to controllable synthesis of MXene and control its thickness to about 5-10nm. In addition, the surface functional groups of MXene greatly affect its electrochemical behavior. The development of suitable surface modification and functional treatment methods to control surface functional groups is particularly important for high-performance batteries.

 Special note: This review is about MXenes and phosphoene materials. We mainly share the content related to MXenes. If you are still interested in phosphoene, please read the corresponding original text. Thank you teachers for your support and attention.

Literature link:

https://doi.org/10.1016/j.nantod.2019.100803

Source: MXene Frontier