在本論文中，利用不同硫醇保護基進行表面修飾金奈米粒子，硫醇保護基可分為兩類，一為含羧酸根的硫醇基，DL-mercaptosuccinic acid (MSA)，Meso-2,3-dimercaptosuccinic acid，4-mercaptobenzoic acid，二為中性的烷基硫醇，四烷基硫醇和十二烷基硫醇。在進行氧化及還原反應的過程，MSA會不可逆的脫附從金奈米粒子的表面，然而四烷基硫醇和十二烷基硫醇卻不會發生此現象。在溶液中的保護基與金奈米粒子表面保護基之交換實驗中，烷基硫醇修飾的金奈米粒子沒有與溶液中的MSA交換，但可能有雙硫醇產物的形成，此產物的形成可能與金奈米粒子和O2 有關。最後，催化的實驗發現，未修飾的金奈米粒子催化效果最好，MSA修飾的金奈米粒子次之，烷基硫醇修飾的金奈米粒子則最差。 Several protecting molecules were employed to modify the surface of gold nanoparticles (AuNPs). The extra functional groups of the protecting thiol molecules used are both carboxylice acid and alkane in the other end. DL-mercaptosuccinic acid, meso-2,3-dimercaptosuccinic acid, and 4-mercaptobenzoic acid are included in the former. The latter contains of 1-butanethiol and 1-dodecanethiol. Furthermore, the activities of the thiol-protected gold nanoparticles were studied in redox reactions. MSA irreversibly desorbed from the surface of the AuNPs in the process. But the similar phenomenon could not be observed for 1-butanethiol and 1-dodecanethiol. In the thiol-exchange reaction for free thiol in solution and thiol-protected AuNPs, alkyl thiol-modified gold nanoparticles did not exchange with the free MSA, but a product of dithiol could be formed. The formation of could be related to both gold nanoparticles and O2. Finally, the catalytic experiments show that AuNPs has the highest catalytic activity compared with MSA-modified AuNPs and alkyl-thiol modified AuNPs with the poor activity.
