Low-temperature synthesis of one-dimensional ZnO nanostructures on screen-printed carbon nanotube films

One-dimensional (1D) ZnO nanostructures including nanowires, nanobelts, and nanorods were synthesized on screen-printed multi-walled carbon nanotube (MW-CNT) films in a thermal chemical vapor deposition process by gold (Au) nanoparticle-catalyst and self-catalyst driving at low temperatures of 400 and 500 °C. ZnO nanowires and nanobelts by introducing Au nanoparticles were grown via the vapor-liquid-solid (VLS) mechanism, while ZnO nanorods were realized via a self-catalytic VLS process. It was found that the diameter of ZnO nanowires strongly depends on that of Au nanoparticles, indicating the typical metal catalyst-driving VLS process. On the other hand, ZnO nanorods without Au-alloyed tips are comprised of hexagonal facets, suggesting self-catalytic VLS formation of the ZnO nanorods on the MW-CNT films. Room temperature photoluminescence spectra of the 1D ZnO nanostructures exhibit an ultraviolet emission band around 378 nm and deep-level emission band centered around 505 nm.