Preparation Of Se Nanowires And Its Formation Mechanisms

Preparation methods of nanowires are reviewed in the paper, espically that of Se nanowires. Based on the results of the literature research, the work for preparation of Se nanowires is proposed. The experimental results show that the reaction and setting solvent, temperatue and time, as well as the concentration of H2SeO3 have significant effects on the formation of Se nanowires. The experimental results demonstrate that water is better solvent for Se nanowire formation than alcohol is. In the process of Se nanowires formation, the low slution temperature lowers the solubility of Se atoms, and the high solution deteriorates the anisotropic growth of Se nuclei. The faviorate setting temperature for Se nanowires growth is below 40oC and higher than 10 oC. The setting time in the process of Se nanowires growth is important to obtain high quality Se nanowires. The concentration of H2SeO3 has obviously effects on both t-Se nuclation and their growth.A new method for preparation of Se nanowires is established. The new approach is related to the formation ofα-Se precipitate in a dense solution, the formation of t-Se nuclei in a dilute solution, and then mix the above mentioned solutions. The process can be operated at ambient conditions. The results show that, t-Se nuclei formation is the key factor for Se nanowire formation, and Se nanowires can be obtained through the control of H2SeO3 concentration.Some interesting morphologies of Se nanostructures are also obtained in the products. The research on their formation mechanism is in progress.