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Title: Morphology modification of gold nanoparticles from nanoshell to C-shape: Improved surface enhanced Raman scattering

Abstract

Morphology modification of nanostructures is of great interest, because it can be used to fabricate nanostructures which are hard to be done using other methods. Different from traditional lithographic technique which is slow and expensive, morphology modification is easy, cheap, and reproducible. In this paper, modification of the optical and morphological properties of a hollow gold nanoshell (HGNS) is achieved by using H{sub 2}O{sub 2} as an oxidizer. The reshaping of these nanostructures has been demonstrated as a consequence of an oxidation process in which HGNSs are dissolved by H{sub 2}O{sub 2} under the acidic conditions provided by HCl. We investigate the oxidation process by a transmission electron microscope and propose a reshaping model involving four different shapes (HGNS, HGNS with hole, gold nanoring, and C-shaped gold nanoparticle) which are corresponding to the oxidation products of HGNSs at different pH values. Besides, the surface enhanced Raman scattering (SERS) activity of each oxidation product has been evaluated by using rhodamine 6G as the Raman active probe. It has been observed that the C-shaped gold nanoparticles which are corresponding to the oxidation products at the minimum pH value have the highest SERS activity and this result can also be interpreted by discrete-dipolemore » approximation simulations. We demonstrate that the morphology modification of HGNSs becomes possible in a controlled manner using wet chemistry and can be used in preparation of gold nanoparticles such as HGNS with hole, gold nanoring, and C-shaped gold nanoparticle with large SERS activity. These nanostructures must have potential use in many plasmonic areas, including sensing, catalysis, and biomedicine.« less

Authors:
; ; ;  [1]
  1. The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049 (China)
Publication Date:
OSTI Identifier:
22596659
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 24; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; APPROXIMATIONS; CATALYSIS; COMPUTERIZED SIMULATION; DIPOLES; GOLD; HOLES; HYDROCHLORIC ACID; HYDROGEN PEROXIDE; MODIFICATIONS; MORPHOLOGY; NANOPARTICLES; NANOSTRUCTURES; OXIDATION; PH VALUE; RAMAN EFFECT; RHODAMINES; SURFACES; TRANSMISSION ELECTRON MICROSCOPY; WATER

Citation Formats

Xing, Ting-Yang, Zhu, Jian, Li, Jian-Jun, and Zhao, Jun-Wu, E-mail: nanoptzhao@163.com. Morphology modification of gold nanoparticles from nanoshell to C-shape: Improved surface enhanced Raman scattering. United States: N. p., 2016. Web. doi:10.1063/1.4954977.
Xing, Ting-Yang, Zhu, Jian, Li, Jian-Jun, & Zhao, Jun-Wu, E-mail: nanoptzhao@163.com. Morphology modification of gold nanoparticles from nanoshell to C-shape: Improved surface enhanced Raman scattering. United States. doi:10.1063/1.4954977.
Xing, Ting-Yang, Zhu, Jian, Li, Jian-Jun, and Zhao, Jun-Wu, E-mail: nanoptzhao@163.com. 2016. "Morphology modification of gold nanoparticles from nanoshell to C-shape: Improved surface enhanced Raman scattering". United States. doi:10.1063/1.4954977.
@article{osti_22596659,
title = {Morphology modification of gold nanoparticles from nanoshell to C-shape: Improved surface enhanced Raman scattering},
author = {Xing, Ting-Yang and Zhu, Jian and Li, Jian-Jun and Zhao, Jun-Wu, E-mail: nanoptzhao@163.com},
abstractNote = {Morphology modification of nanostructures is of great interest, because it can be used to fabricate nanostructures which are hard to be done using other methods. Different from traditional lithographic technique which is slow and expensive, morphology modification is easy, cheap, and reproducible. In this paper, modification of the optical and morphological properties of a hollow gold nanoshell (HGNS) is achieved by using H{sub 2}O{sub 2} as an oxidizer. The reshaping of these nanostructures has been demonstrated as a consequence of an oxidation process in which HGNSs are dissolved by H{sub 2}O{sub 2} under the acidic conditions provided by HCl. We investigate the oxidation process by a transmission electron microscope and propose a reshaping model involving four different shapes (HGNS, HGNS with hole, gold nanoring, and C-shaped gold nanoparticle) which are corresponding to the oxidation products of HGNSs at different pH values. Besides, the surface enhanced Raman scattering (SERS) activity of each oxidation product has been evaluated by using rhodamine 6G as the Raman active probe. It has been observed that the C-shaped gold nanoparticles which are corresponding to the oxidation products at the minimum pH value have the highest SERS activity and this result can also be interpreted by discrete-dipole approximation simulations. We demonstrate that the morphology modification of HGNSs becomes possible in a controlled manner using wet chemistry and can be used in preparation of gold nanoparticles such as HGNS with hole, gold nanoring, and C-shaped gold nanoparticle with large SERS activity. These nanostructures must have potential use in many plasmonic areas, including sensing, catalysis, and biomedicine.},
doi = {10.1063/1.4954977},
journal = {Journal of Applied Physics},
number = 24,
volume = 119,
place = {United States},
year = 2016,
month = 6
}
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