Scalable Manufacturing of Free‐Standing, Strong Ti3C2Tx MXene Films with Outstanding Conductivity

• Published in: Advanced materials (Weinheim) 2020-06, Vol.32 (23), p.n/a
• Main Authors: Zhang, Jizhen, Kong, Na, Uzun, Simge, Levitt, Ariana, Seyedin, Shayan, Lynch, Peter A., Qin, Si, Han, Meikang, Yang, Wenrong, Liu, Jingquan, Wang, Xungai, Gogotsi, Yury, Razal, Joselito M.
• Format: Article
• Language: English
• Subjects: aligned films; Alignment; electrical conductivity; Electrical resistivity; electromagnetic interference shielding; Electromagnetic shielding; Flakes; Flexible components; High strength; MXene films; MXenes; Tensile strength; Thickness
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202001093

Free‐standing films that display high strength and high electrical conductivity are critical for flexible electronics, such as electromagnetic interference (EMI) shielding coatings and current collectors for batteries and supercapacitors. 2D Ti3C2Tx flakes are ideal candidates for making conductive films due to their high strength and metallic conductivity. It is, however, challenging to transfer those outstanding properties of single MXene flakes to macroscale films as a result of the small flake size and relatively poor flake alignment that occurs during solution‐based processing. Here, a scalable method is shown for the fabrication of strong and highly conducting pure MXene films containing highly aligned large MXene flakes. These films demonstrate record tensile strength up to ≈570 MPa for a 940 nm thick film and electrical conductivity of ≈15 100 S cm−1 for a 214 nm thick film, which are both the highest values compared to previously reported pure Ti3C2Tx films. These films also exhibit outstanding EMI shielding performance (≈50 dB for a 940 nm thick film) that exceeds other synthetic materials with comparable thickness. MXene films with aligned flakes provide an effective route for producing large‐area, high‐strength, and high‐electrical‐conductivity MXene‐based films for future electronic applications. Strong and highly conductive binder‐free Ti3C2Tx MXene films with excellent electromagnetic interference shielding performance are fabricated by a blade‐coating method using high‐aspect‐ratio MXene flakes. Achieving such a combination of properties using a scalable fabrication process enables manufacturing of MXene‐based high‐performance devices and new applications.