AM: The conductivity is 15100S / cm, a record! High-strength MXene shielding film

   Flexible films with high strength and excellent electrical conductivity are critical for flexible electronic devices, such as shielding coatings and current collectors for batteries and supercapacitors. With excellent mechanical strength and metal conductivity, two-dimensional Ti 3 C 2 T x flakes are ideal materials for preparing conductive films. However, due to the small size and relatively poor orientation, macro-scale films still have greater challenges to inherit these excellent properties of single-layer MXene sheets.

Achievements

     Recently, Deakin University of Joselito M. Razal professor in the top international journal Advanced Materials published entitled " Scalable Manufacturing of as Free-Standing, Strong Ti 3 C 2 T the X-  MXene Films with Outstanding Conductivity " papers. A highly oriented MXene film with high strength and excellent electrical conductivity that can be prepared on a large scale is shown. These films achieved a record tensile strength of 570 MPa (940 nm thick) and an electrical conductivity of approximately 15100 S cm ⁻¹ (214 nm thick), all of which reached the highest values reported for pure MXene films to date . In addition, the film‘s shielding performance is as high as 50 dB (940 nm thick), which is superior to other shielding materials of comparable thickness. The orientation of MXene sheets provides an effective way for the preparation of MXene-based thin films for future electronic applications with large area, high strength and high conductivity.

Figure  1  Schematic diagram of the preparation of large-size MXene sheets.

Figure  2  Schematic diagram of the blade coating process.

Figure  3  Bending test of MXene film .

Picture  4 Orientation test of MXene film by knife coating and suction filtration .

in conclusion

      In short, the pure Ti 3 C 2 T x  MXene thin film with high strength and excellent electrical conductivity was prepared with the aid of the mass production blade coating process and the use of large-size MXene sheets . By preselecting a large-size MAX phase and adjusting the etching conditions, a high aspect ratio MXene sheet is obtained. In addition, the formation of liquid crystal MXene and suitable rheological properties enable the sheet to form a highly oriented MXene film under shear . These advantages enable the MXene film to achieve a record tensile strength of 570 MPa , a Young‘s modulus of 20.6 GPa , and a conductivity of 15100 S cm ⁻¹ . This work will further expand the application of MXene -based films in electromagnetic shielding, energy storage, and printing electronics.

Original link:

https://onlinelibrary.wiley.com/doi/full/10.1002/adma.202001093

Source: MXene Academic