Fig. 2

The MXene’s typical microstructure and the in situ dynamic process under an external pressure. a Cross-sectional TEM image of the MXene and its two insets shows the lamellar structure. b The MXene’s plan view HRTEM image and its corresponding diffraction pattern in the inset, showing well the hexagonal characteristics. c In an in situ force instrument, a nanoindenter supported by a tapered needle point is locally applied on the FIB processed MXene sample. d–f The wider distance in the MXene suffers a rapidly decrease under the external force, from ~12 nm, via ~3 nm to ~0 nm at 7, 9 and 10 s in sequence. g–i The narrower distance (4 spacings) labeled by a red line ranges from 5.23 nm, via 4.98 nm then to 4.81 nm at 7, 9 and 10 s in sequence. j–l The analysis on g–i using the digital micrograph software. Measured from the original state in g, the strain values were 4.78 and 8.03% at the states h, i, respectively. Scale bar for a, b is 4 nm, c is 200 nm, d–f is 40 nm and g–i is 20 nm