Multi-probe Imaging for Materials

Understanding the Behaviour of 2D Ti3C2Tx MXene Nanosheets for Fibre Formation using SAXS-WAXS and FIB-SEM Techniques

Not scheduled

20m

Auditorium (ESRF )

Poster

Speaker

Ms Kim Marie Sisican (Deakin University)

Description

The advent of new materials has led to the development of multifunctional fibres with unique properties, such as electrical conductivity, energy harvesting/storage capacities, and sensing capabilities [1-2]. Since the discovery of two-dimensional (2D) MXene, specifically Ti₃C₂T_x, there has been various research on its fabrication into functional fibres due to its excellent inherent electrical and electrochemical properties [3-4]. However, the production of pure MXene fibres has been limited due to their weak mechanical strength, which is caused by the random arrangement of the 2D nanosheets, consequently reducing its electrical conductivity and electrochemical properties [5]. Thus, improving the MXene nanosheet alignment within the fibre microstructure is necessary to increasing the fibre strength and its overall properties. This can be achieved by the addition of agents, such as acetic acid (AcOH), which can promote the sheet alignment prior before fibre formation. In this study, different concentrations of AcOH were added to the Ti₃C₂T_x spinning dopes to control the sheet orientation prior to the fibre wet-spinning process. The effects of AcOH were characterized by small-angle X-ray scattering (SAXS) by measuring the nanosheet interlayer spacing, while wide-angle X-ray scattering (WAXS) was also used to determine the sheet orientation within the fibre microstructure at different AcOH concentrations. Focused ion beam – scanning electron microscopy (FIB-SEM) was also used to observe the cross-sectional morphology (e.g., cross-sectional area, sheet alignment, and stacking density) of the MXene fibres. AcOH-treated MXene fibres showed a decrease in the interlayer sheet spacing, increase in the sheet alignment, and a higher stacking density, which promoted the formation of pure MXene fibres with enhanced tensile strengths (up to twice the original untreated fibres). These results offer insights on the feasibility of controlling 2D nanosheet alignment for effectively improving the overall fibre properties.