Abstract
The ability to control the site-selective deposition of a noble metal with nanoscale accuracy is vital for the synthesis of well-defined heterogeneous core-shell bimetallic nanoparticles for various applications ranging from nanophotonics to catalysis. Here, precise site-specific Ag coating onto concave gold nanoarrows (GNAs) is reported by tuning the concentration of the surfactant-cetyltrimethylammonium chloride (CTAC). Three distinct nanocoating structures, namely, anisotropic coating, middle coating, and conformal coating are obtained, which are achieved under low, medium and high CTAC concentrations, respectively. The site-specific nanoscale coating on GNAs is proved by scanning transmission electron microscopy imaging in conjunction with the elemental mapping. The CTAC concentration-dependent, facet-specific passivation may be the cause for the three distinct nanoparticles obtained. The morphology differences resulted in discrete plasmonic features, and a linear relationship between the resonance peak and the CTAC concentration is found for the conformal-coated GNAs. We further fabricate free-standing monolayer nanosheets out of the three kinds of nanoparticles, which display strong shape-dependent SERS enhancements.
| Original language | English |
|---|---|
| Pages (from-to) | 940-946 |
| Number of pages | 7 |
| Journal | Nanoscale Horizons |
| Volume | 4 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - 1 Jul 2019 |
Cite this
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Site-specific Ag coating on concave Au nanoarrows by controlling the surfactant concentration. / Dong, Dashen; Shi, Qianqian; Sikdar, Debabrata; Zhao, Yunmeng; Liu, Yiyi; Fu, Runfang; Premaratne, Malin; Cheng, Wenlong.
In: Nanoscale Horizons, Vol. 4, No. 4, 01.07.2019, p. 940-946.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - Site-specific Ag coating on concave Au nanoarrows by controlling the surfactant concentration
AU - Dong, Dashen
AU - Shi, Qianqian
AU - Sikdar, Debabrata
AU - Zhao, Yunmeng
AU - Liu, Yiyi
AU - Fu, Runfang
AU - Premaratne, Malin
AU - Cheng, Wenlong
PY - 2019/7/1
Y1 - 2019/7/1
N2 - The ability to control the site-selective deposition of a noble metal with nanoscale accuracy is vital for the synthesis of well-defined heterogeneous core-shell bimetallic nanoparticles for various applications ranging from nanophotonics to catalysis. Here, precise site-specific Ag coating onto concave gold nanoarrows (GNAs) is reported by tuning the concentration of the surfactant-cetyltrimethylammonium chloride (CTAC). Three distinct nanocoating structures, namely, anisotropic coating, middle coating, and conformal coating are obtained, which are achieved under low, medium and high CTAC concentrations, respectively. The site-specific nanoscale coating on GNAs is proved by scanning transmission electron microscopy imaging in conjunction with the elemental mapping. The CTAC concentration-dependent, facet-specific passivation may be the cause for the three distinct nanoparticles obtained. The morphology differences resulted in discrete plasmonic features, and a linear relationship between the resonance peak and the CTAC concentration is found for the conformal-coated GNAs. We further fabricate free-standing monolayer nanosheets out of the three kinds of nanoparticles, which display strong shape-dependent SERS enhancements.
AB - The ability to control the site-selective deposition of a noble metal with nanoscale accuracy is vital for the synthesis of well-defined heterogeneous core-shell bimetallic nanoparticles for various applications ranging from nanophotonics to catalysis. Here, precise site-specific Ag coating onto concave gold nanoarrows (GNAs) is reported by tuning the concentration of the surfactant-cetyltrimethylammonium chloride (CTAC). Three distinct nanocoating structures, namely, anisotropic coating, middle coating, and conformal coating are obtained, which are achieved under low, medium and high CTAC concentrations, respectively. The site-specific nanoscale coating on GNAs is proved by scanning transmission electron microscopy imaging in conjunction with the elemental mapping. The CTAC concentration-dependent, facet-specific passivation may be the cause for the three distinct nanoparticles obtained. The morphology differences resulted in discrete plasmonic features, and a linear relationship between the resonance peak and the CTAC concentration is found for the conformal-coated GNAs. We further fabricate free-standing monolayer nanosheets out of the three kinds of nanoparticles, which display strong shape-dependent SERS enhancements.
UR - http://www.scopus.com/inward/record.url?scp=85067955370&partnerID=8YFLogxK
U2 - 10.1039/c8nh00431e
DO - 10.1039/c8nh00431e
M3 - Article
VL - 4
SP - 940
EP - 946
JO - Nanoscale Horizons
JF - Nanoscale Horizons
SN - 2055-6756
IS - 4
ER -