From zinc nanowires to zinc oxide nanowires: a low substrate-temperature approach

We report here a simple two-step approach to produce ZnO nanowires, i.e. preparing Zn nanowires by evaporating Zn powder in a low vacuum and then oxidizing it to ZnO in air. This approach is very simple, catalyst free, and is capable of growing ZnO nanowires at low substrate temperatures; e.g. the substrate temperature for preparing Zn nanowires was similar to 200 degrees C, and that for the oxidation step was 305 +/- 2 degrees C. The ZnO nanowires synthesized by this approach exhibited intense photoluminescence (PL) at similar to 380 nm and weak PL at similar to 450 nm at room temperature. This study provides an alternative method for preparing metal oxide nanostructures at relatively low substrate temperatures.