Chiroptical Study of Metal@semiconductor鈥揗olecule Composites: Interaction between Cysteine and Ag@Ag3PO4 Core鈥揝hell Hybrid Nanorods

详细信息    查看全文

• 作者：Guiqing Cheng ; Jiancheng Di ; Yu Wang
• 刊名：Journal of Physical Chemistry C
• 出版年：2015
• 出版时间：September 24, 2015
• 年：2015
• 卷：119
• 期：38
• 页码：22122-22130
• 全文大小：669K
• ISSN：1932-7455

文摘

The coupling between an inorganic nanostructure and a chiral molecule can give rise to a strong chiroptical response in a range from the UV to visible spectrum. In this work, novel plasmonic Ag@Ag₃PO₄ core鈥搒hell hybrid nanorods (CSHNRs) have been prepared via a wet chemical method. The cysteine molecules can adsorb on the surface of the plasmonic hybrid nanorods, leading to the appearance of new circular dichroism (CD) signals in the UV region. The Ag@Ag₃PO₄鈥揷ysteine CSHNRs show a similar CD spectrum to the Ag₃PO₄鈥揷ysteine polyhedral nanocrystals (PNCs), although they have different morphology and structure. The Ag@Ag₃PO₄鈥揷ysteine CSHNRs and Ag₃PO₄鈥揷ysteine PNCs have a stronger chiroptical response than the Ag鈥揷ysteine nanorods (NRs) attributed to the effect of phosphate groups. This indicates that the Ag⁺ ions on the surface of nanostructures can promote the formation of S鈥揝 bonds of oxidized cysteine under acidic conditions, rendering the uniformity of molecular conformation on the surface of nanostrucures, thus giving rise to the strong chiroptical response. Furthermore, the Ag@Ag₃PO₄ CSHNRs can spontaneously form a chiral liquid crystalline phase upon dispersion in the ethylene glycol solution owing to their large aspect ratio and the optimum solvating effect of ethylene glycol.