The structure and photoluminescence properties of ZnO nanobelts prepared by a thermal evaporation process

ZnO nanobelts had been synthesized by a simple method of thermal evaporation of Zn powders. The morphology, structure and photoluminescence (PL) properties of ZnO nanobelts were studied. The nanobelts had a single-crystal hexagonal structure and grew along the (0 0 0 1) direction with several micrometers long, 50-400 nm wide and 30-100 nm thick. Photoluminescence measurement showed that the nanobelts had an intensive near-band ultraviolet emission at about 3.3 eV. The obtained experimental data suggest that the ultraviolet PL in ZnO nanobelts originates from the recombination of the acceptor-bound excitons and free extions at room temperature. The absence of the deep level emission indicated very low impurity concentration and high crystalline quality in the ZnO nanobelts. Large-area growth and high quality indicate that the prepared ZnO nanobelts have potential application in optoelectronic devices.