Alkylammonium Cation Intercalation into Ti3C2 (MXene): Effects on Properties and Ion-Exchange Capacity Estimation

作者：Ghidiu Michael; Kota Sankalp; Halim Joseph; Sherwood Alexander W; Nedfors Nils; Rosen Johanna; Mochalin Vadym N^*; Barsoum Michel W^*

来源：Chemistry of Materials, 2017, 29(3): 1099-1106.

DOI：10.1021/acs.chemmater.6b04234

Ti3C2Tx MXene intercalated with Li+ ions was produced and ion-exchanged with a series of trimethylalkylammonium (AA) cations of increasing alkyl chain length. A discontinuous expansion in the MXene layer spacing was observed, attributed to complete packing of the interlayer space at a critical chain length. The latter was used to estimate the number of cations per Ti3C2 formula unit, which was found to be in good agreement with a similar quantification obtained from X-ray photoelectron spectroscopy, energy-dispersive spectroscopy, and elemental analysis. The system was also modeled using density functional theory and molecular dynamics, arriving at cation concentrations in the same range. The intercalated AA cations led to tunable increases in resistivity of the normally highly electrically conductive MXene and were investigated as interlayer pillars in electrochemical capacitors.

• 出版日期2017-2-14