Low temperature growth of single-crystal ZnO nanorods

ZnO nanorods are grown on large-area glass substrates with a ZnO overlayer by an aqueous solution method at temperatures ranging from 65 °C down to room temperature. The structure and morphology of the nanorods is studied with electron microscopy. They are single crystalline and grow preferentially perpendicular to the substrate. Their aspect ratio can be tailored by modifying the growth parameters. Self-assembly and subsequent selective growth of the nanorods is accomplished in pre-patterned substrates. Room temperature photoluminescence measurements reveal a strong band edge emission at 378 nm, while no defect-related visible emission is detected except for the nanorods grown at RT.