Figure 3: Vertical-to-horizontal transition from 400 to 780 °C.
From: Direct TEM observations of growth mechanisms of two-dimensional MoS2 flakes
(a–e) TEM images versus the increasing temperatures: (a) 400 °C, (b) 500 °C, (c) 600 °C, (d) 700 °C and (e) 780 °C. The insets in a,c,e are the corresponding fast Fourier transform (FFT) patterns. The red arrows in d denote the vertical MoS2 structures at 700 °C to provide better illustration. Scale bars, 20 nm. (f) Statistical distribution of the counts of the vertical MoS2 flakes in frames a–e. (g) The energy density of MoS2 structures along two orientations as a function of their volumes, showing the competition of total system energy between the vertical and horizontal structures during crystal growth. (h) Schematic process of the vertical-to-horizontal transition.
