Modelling the growth of ZnO nanocombs based on the piezoelectric effect

In this work a model for the growth of ZnO nanocombs based on the piezoelectric character of ZnO is presented that explains the periodic growth of nanowire branches on the polar +(0001) surface of a ZnO nanobelt as a self catalytic growth process. In this model the perturbation and elasticity theory are applied to approximate the induced mechanical strain and piezoelectric potential distribution in the nanobelt under the growth kinetics. To implement a quantitative simulation of the periodic growth of ZnO nanobranches the induced piezoelectric charges in the ZnO nanostructure are calculated. These are responsible for the structural transformation from a nanobelt into a nanocomb. A comparison with nanocombs that are synthesized using the vapor-liquid-solid method shows good agreement between experimental and theoretical results.