Polarity and inverse boundary of Sn-doped ZnO bicrystal nanobelts determined by electron energy-loss spectroscopy

Polarity in Sn-doped ZnO bicrystal nanobelts has been investigated using electron energy-loss spectroscopy. The nanobelts are composed of two domain boundaries extending along the axial direction. It is confirmed that the nanobelts are Zn terminated at both sides. Examinations of high-resolution transmission electron microscopy and electron energy-loss spectroscopy show that one domain boundary results from a stacking fault, and the other originates from Sn-ion insertion, which leads to an inverse domain boundary. A possible atomic stacking model is proposed.