Hydrothermal route to ZnO nanocoral reefs and nanofibers

ZnO nanocoral reefs and nanofibers are synthesized on the glass substrate dip coated with ZnO seed with nanoparticles with an average size of 5 nm under a hydrothermal reaction. The ratios of length to diameter for the former and the latter are determined to be 100 and 1000, respectively. In addition, we found that a threshold power density for UV lasing action could be remarkably reduced from 40 kW/cm(2) for the nanocoral reefs to 8 kW/cm(2) for the nanofibers by increasing the cavity length of ZnO nanowires. (C) 2004 American Institute of Physics.