Extended Data Fig. 7: Multicycle tensile fracture tests of DSC NBs in TEM and SEM.
a and b, TEM snapshots of a rectangular DSC NB along the [100] direction (~ 350 nm in width, 100 nm in thickness and 1500 nm in gauge length). SAED Patterns were taken from circled regions in a and b. c, TEM image taken from the red framed region in b, showing the typical {111} cleavage fracture. The inset is a diagram showing the geometry of two intersecting {111} cleavage surfaces. d to g, TEM images of the fractured surfaces of the DSC NB, taken after the initial tensile fracture and 1st to 3rd healing tests. h to k, HRTEM images from the surface regions in d to g, respectively (insets, corresponding fast Fourier transform images). The single-crystallinity was maintained throughout multicycle fracture and healing, with almost no DOs formed on the surface. l, SEM observations of a DSC NB ( ~ 205 nm in width, along the <100 > ) during the tensile fracture test. m, High magnification SEM image of the fractured ends, showing typical {111} cleavage fracture; n, SEM image of the fractured region after release the load. The inset shows the geometry of two intersecting {111} cleavage surfaces. o, Load versus displacement curves from the multicycle tensile fracture test. p, Healing efficiency versus healing duration of the three DSC NBs with width of ~200 nm along <100 > , <110> and <111> direction.
