Preparation of Two-dimensional Ti₂CT _x by Molten Fluorinated Salt Method

Abstract

We prepared a two-dimensional transition metal carbide Ti₂CT _x by treatment of Ti2AlC in molten fluoride salt. Two fluorinated salt systems were used to etch Al from Ti₂AlC powder precursor under the argon atmosphere, and then the resulting MXene was delaminated with TBAOH to produce few-layered nanosheets of Ti₂CT _x. The reaction was undergone at different temperatures to study the effect of temperature. The results show that the optimal reaction temperature is 600 °C in LiF-NaF-KF system, and 850 °C in NaFKF system. The molten salt treated products are delaminated and quasi-2D MXene sheets can be obtained. The thickness of the MXene sheets prepared from the binary molten salt system is smaller than that of the ternary molten salt system.

Keywords

Ti₂CT _x / 2D structure / fluoride salts / etching

References

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