Fig. 2

Structural characterizations of acute-angled and obtuse-angled twinned Au nanokites. a Transmission electron microscopy (TEM) image of an acute-angled twinned nanokite and e the corresponding selected area electron diffraction (SAED) pattern. b High-magnification TEM image of the acute-angled twinned Au nanokite with marked areas and f–h their corresponding fast Fourier transform (FFT) patterns. (0 0 0 4), (1 0 \(\bar 1\) 0), and (1 0 \(\bar 1\) 2) spots of 4H phase are marked with pentagons, circles, and squares, respectively. The orange and blue represent different 4H sub-crystals. c High-resolution TEM (HRTEM) image of the twin boundary of the acute-angled twinned nanokite. The twin boundary is marked in turquoise line. d Angle distribution histogram of acute-angled twinned nanokites and a nanokite model showing the measured angle. i TEM image of an obtuse-angled twinned nanokite and m the corresponding SAED pattern. j High-magnification TEM image of the obtuse-angled twinned Au nanokite with marked areas and n–p their corresponding FFT patterns. k HRTEM image of the twin boundary of the obtuse-angled twinned nanokite. The twin boundary is marked in turquoise line. l Angle distribution histogram of obtuse-angled twinned nanokites and a nanokite model showing the measured angle. Scale bars, a, i 50 nm; b, j 20 nm; c, k 2 nm