Synthesis process, thermal and electrical behaviors of Ti3C2Tx MXene Syntheseprozess, thermisches und elektrisches Verhalten von Ti3C2Tx MXene

Abstract

Synthesis of two-dimensional (2D) titanium carbide (Ti₃C₂T_x), with the name of MXene, by etching Ti₃AlC₂ (MAX) for different times 20 (v/v) % hydrofluoric acid (HF) at 40 °C was carried out. The influences of time, temperature and source of MAX on the synthesis of MXene were researched. The MXenes produced were characterized by fourier-transform ınfrared (FT-IR) spectroscopy technique, energy dispersive x-ray spectroscopy (EDX), scanning electron microscopy (SEM), x-ray diffraction (XRD) and thermogravimetry (TG) instruments. Above 390 °C, MXene layers were considerably oxidizing and forming anatase and rutile phases of TiO₂ under air atmosphere. The resistance of MAX and MXene was 3.6 Ω and 116 Ω, respectively. However, the resistance of the residual part of MXene heated to 620 °C considerably increased to 17850 Ω. This behavior is another important piece of evidence showing that the MXene crystal structure has changed significantly and transformed into a new chemical structure containing anatase and rutil titanium oxide (TiO₂). The dielectric loss (ϵ’’) and alternating conductivity (δ_ac) of the MAX and MXenes were determined from their impedance measurements. The ϵ’’ and δ_ac values of MXene were compared with those of MAX. Direct curent conductivities of MAX and MXene produced for 24 h were found to be 0.016 S/cm and 0.0023 S/cm, respectively.