Luminescence anisotropy of ZnO microrods

► ZnO luminescence spectra are significantly influenced by the crystal morphology. ► The ultraviolet NBE emission occurs primarily from the top (0001) planes of ZnO. ► The visible deep-level emission occurs dominantly from the side facets. ► RT PL spectra consists of a few overlapping peaks due point and surface defects. ► The ZnO luminescence anisotropy may be crucial for the design of optoelectronic devices.