Morphology, structures and properties of ZnO nanobelts fabricated by Zn-powder evaporation without catalyst at lower temperature

Uniform ZnO normal nanobelts and toothed-nanobelts have been successfully synthesized respectively through pure zinc powder evaporation without catalyst at 600°C. Experimental results indicate that the key to the fabricating method is to control the gas flow rates and the partial pressures of argon, oxygen and zinc vapor. Scanning electron microscopy and high-resolution transmission electron microscopy observations show that the ZnO nanobelts have several types of single crystalline morphology. HRTEM images reveal that there are numerous screw dislocations and the growth is around the dislocations in the toothed-nanobelts. The growth of ZnO nanobelts is controlled by vapor-solid and screw dislocation mechanisms. Room temperature photoluminescence spectra of the toothed-nanobelts showed a UV emission at ∼390 nm and a broad green emission with 4 subordinate peaks at 455–495 nm.