Synthesis of MAX Phase Nanofibers and Nanoflakes and the Resulting MXenes

Hui Shao (1, 2) , Sha Luo (3, 1) , Armel Descamps-Mandine (4) , Kangkang Ge (1, 2) , Zifeng Lin (5) , Pierre‐louis Taberna (1, 2) , Yury Gogotsi (6) , Patrice Simon (1, 2)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
2 RS2E - Réseau sur le stockage électrochimique de l'énergie
3 Lanzhou University
4 Centre Castaing - Centre de microcaractérisation Raimond Castaing
5 SCU - Sichuan University [Chengdu]
6 Drexel University

Layered ternary carbides and nitrides, also known as MAX phases, have attracted enormous attention for many applications, especially as precursors to produce 2D metal carbides and nitrides called MXenes. However, it is still challenging to tune and control the shape/morphology of MAX phase particles at the nanoscale, as they are typically manufactured as large grains using ceramic technology. Herein, nanostructured Ti-Al-C MAX phases with fine-tuned morphology of nanofibers and nanoflakes are prepared by using 1D and 2D carbon precursors at a synthesis temperature of 900 °C. The nanostructured MAX phases are used as precursors to produce nanosized multilayered MXenes, with a considerably shorter etching time and a low reaction temperature. These nanosized MXenes exhibit good electrochemical lithium-ion storage properties and a pseudocapacitive electrochemical signature. The obtained Ti2CTx MXene electrode can deliver delithiation capacity of 300 mAh g−1 at low rates and 100 mAh g−1 when the lithiation/delithiation cycle happens within 30 s. Availability of nanoscale MAX phases and MXene nanoflakes with small lateral size may open new opportunities for both classes of materials.

Mots clés: Layered ternary carbide; MAX phase; molten salt; nanofibers; nanoflakes; nanosized multilayered MXene; pseudocapacitive Li-ion storag

Domaines: Matériaux; Sciences de l'ingénieur [physics]

Hui Shao, Sha Luo, Armel Descamps-Mandine, Kangkang Ge, Zifeng Lin, et al.. Synthesis of MAX Phase Nanofibers and Nanoflakes and the Resulting MXenes. Advanced Science, 2023, 10 (1), pp.2205509. ⟨10.1002/ADVS.202205509⟩. ⟨hal-03937060⟩