Thermal and solvent composition assisted adsorption of gold nanoparticles on silanized silicon substrates
| Autor: | Yu-Che Huang, 黃鈺哲 |
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| Rok vydání: | 2018 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 106 We adjusted the solvent composition and temperature to observe the patterns of adsorbed gold nanoparticles on organsilanized silicon substrates and studied the coverage of gold nanoparticles for different factors. We used chemical reduction method to synthesize the colloidal gold solution. Then the gold nanoparticle submonolayer films were formed by deposition of gold nanoparticles on ( 3- Aminopropyl )- trimethoxysilan ( APTMS ) covered substrates. When the deposition time increases, the number of adsorbed gold nanoparticle also increases. If the time was long enough, the nanoparticles adsorption became saturated. The time and the coverage of gold nanoparticles show a positive correlation. We also found the difference of solvent would induce the gold nanoparticles gather, and make the coverage change. If we used the ethanol solution, the coverage even dropped to 7 %. When we deposited the samples with thiols, the short carbon chain attracted more gold nanoparticles on the sample surface. It made the surface charge decrease and the repulsive force also became weak. In the three different thiols, pentanethiols, hexanethiols and heptanethiols, the coverage of gold nanoparticles with heptanethiol reached the largest value - 18 %. Then if we used the thiols to treat the sample surface twice, the coverage of nanoparticles with pentanethiols increased to the largest value - 34 %. Last, we observed the effect of temperature to the coverage of surface. When the temperature rose, nanoparticles gathered with the rising of the coverage. However, when the temperature was higher than 60 ˚C, the coverage of gold nanoparticles decreased. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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