Tailored synthesis and morphological analysis of Mo2CTx and Ti3C2Tx MXenes: a study on multilayered and delaminated architectures

Abstract

MXenes, a family of two-dimensional transition metal carbides, nitrides, and carbonitrides, display high conductivity, large surface area, hydrophilicity, and biocompatibility. This work demonstrates a comparative scalable synthesis of multilayer (m-MXene) and delaminated (d-MXene) Mo₂CT_x and Ti₃C₂T_x from their MAX phases (Mo₂Ga₂C and Ti₃AlC₂) using optimized HCl/HF/DI water etchants (ratios of 6 : 3 : 1 for Mo₂Ga₂C and 6 : 1 : 3 for Ti₃AlC₂) via an LiCl-assisted delamination strategy. Significant interlayer expansion is confirmed by XRD (002) peak shifts (from 9.81° to 8.03° for Mo₂CT_x and from 9.51° to 8.80° for Ti₃C₂T_x), while their lateral sizes reached 2–5 µm for Ti₃C₂T_x and 0.5–1 µm for Mo₂CT_x. The UV-Vis spectra showed characteristic absorption peaks at 209, 230, 295, and 568 nm for Mo₂CT_x and at 263, 325, and 798 nm for Ti₃C₂T_x, confirming their delamination and distinctive electronic structure. Thorough structural and compositional characterizations (UV-Vis spectroscopy, XRD, HR-SEM, EDS, Raman spectroscopy, and FTIR spectroscopy) verified the successful synthesis of MXenes. This study provides the first direct systematic comparison of Mo₂CT_x and Ti₃C₂T_x MXenes, establishing benchmarks for the scalable production and applications of MXenes.