Cathodoluminescence of Single Disk-Like ZnO Prepared by Low Temperature Solution-Based Method

Single crystalline ZnO disk-like structure with good luminescent properties was obtained by a low temperature solution based method. Micro-emulsion was employed to assist the shape control. The product has a perfect hexagonal shape with flat bottom and up surfaces, and has a wide size distribution, the size ranges from nano to micro-scale. Electron diffraction (ED) pattern coupled with transmission electron microscopy (TEM) indicate that the single disk was single-crystalline. In cathodoluminescence (CL) studies at room temperature for wavelengths between 350 and 675 nm, we have observed a single exciton peak around 390 nm without any deep-level emission. The monochromatic CL mapping in the ultra-violet (UV) region has such properties as: the intensity is concentrated along the boundary of the cavity; the emission is predominantly at the corner. [DOI: 10.1380/ejssnt.2009.354]