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ZnO nanowire arrays were synthesized on zinc foil by a simple thermal evaporation process at relatively low temperature. Morphology and size controlled synthesis of the ZnO nanostructures was achieved by variation of the synthesis temperature, reaction time and the surface roughness of the substrate. A gas-solid and self-catalytic liquid-solid mechanism is proposed for the growth of nanowires at different temperatures. High-resolution transmission electron microscopy (HRTEM) showed that the as-grown nanowires were of single crystal hexagonal wurtzite structure, growing along the [101] direction. Photoluminescence exhibited strong UV emission at ∼382 nm and a broad green emission at ∼513 nm with 325 nm excitation. Raman spectroscopy revealed a phonon confinement effect when compared with results from bulk ZnO. The nanowire arrays also exhibited a field emission property.

Large-scale ZnO nanowire arrays with honeycomb-like micropatterns have been synthesized by a surfactant assisted soft chemical approach. Sol–gel-derived ZnO thin film with crystallographic orientation along the c axis was used as a substrate for the growth of ZnO nanowires. The micropatterned arrays of ZnO nanowires also exhibited strong crystallographic orientation along the c axis. Experimental parameters were varied to explore the possible growth mechanism of the nanowires as well as the micropatterned arrays formed by the ZnO nanowires. The room temperature photoluminescence studies revealed that the ZnO nanowire arrays exhibited a strong UV emission peak at ~3.22 eV ascribed to the band edge emission.