From the absolute surface energy to the stabilization mechanism of high index polar surface in wurtzite structure: The case of ZnO

An improved wedge-shape method is employed to calculate the absolute surface energies of wurtzite ZnO high index polar surfaces. From the viewpoints of atomic structure and surface energy, the stabilization mechanism of high index polar surfaces is systematically investigated. Under different conditions (O and Zn rich), the stable surface structures are discussed, and it is found that some high index polar surfaces may have lower surface energy than conventional (101¯0) or (0001) surfaces. This may be of vital importance to the surface morphology of nanostructures. In addition, the calculation results are well in agreement with experimental observations. The present theoretical and experimental work can provide important insights to the growth and surface treatment of complex nanostructures.