Controllable growth and optical properties of large scale ZnO arrays

Well-aligned and high-quality ZnO whisker arrays were prepared through a very simple solvothermal method at low temperature. The orientation of the whiskers was effectively controlled by simply adjusting the reaction conditions and confirmed with SEM observations and XRD analysis. The quality of the arrays could be modulated by the growth temperature, which was reflected in the photoluminescence spectra. Stimulated emission (multimode lasing) was observed in the arrays.