Well-crystallized zinc oxide quantum dots with narrow size distribution
In this study, pulsed laser ablation, online annealing, and following size classification using a differential mobility analyzer (DMA) were employed to fabricate quantum dots (QDs) of zinc oxide (ZnO). The irregularly shaped ZnO particles were obtained at annealing temperature less than 873 K, which gradually transformed into spherical QDs with increasing the annealing temperature. Finally, ZnO QDs with narrow size distribution having spherical shapes were successfully obtained at temperatures above 1173 K under the DMA classification at a nominal size of 10 nm. TEM observation demonstrated that the ZnO QDs obtained by this process were well-crystallized single crystallites with a wurtzite structure. Further, ZnO QDs with average sizes in the range of 4.8–8.1 nm were successfully fabricated by reducing the specified sizes of DMA. These features of the fabricated ZnO QDs are favorable for investigation of intrinsic quantum size effect in ZnO.
KeywordsZinc oxide Quantum dot Laser ablation Differential mobility analyzer Particle synthesis
- Chang HJ, Lu CZ, Wang Y, Son CS, Kim SI, Kim YH et al (2004) Optical properties of ZnO nanocrystals synthesized by using sol-gel method. J Korean Phys Soc 45:959–962Google Scholar
- Hirasawa M, Orii T, Seto T (2005) Synthesis of visible-light emitting Si nanoparticles by laser nano-prototyping. J Aerosol Res 20:103–107Google Scholar
- Seol KS, Ohki Y, Takeuchi K (2004) Recent development of differential mobility analyzer for size-classification of nanoparticles and their applications to nanotechnologies. KIEE Int Trans EA 4C:39–44Google Scholar