Surface enhanced Raman spectroscopy: A re-examination of the role of surface roughness and electrochemical anodization

Steven G. Schultz; Maria Janik-Czachor; R. P. Van Duyne

doi:10.1016/0039-6028(81)90069-8

Surface enhanced Raman spectroscopy: A re-examination of the role of surface roughness and electrochemical anodization

Steven G. Schultz, Maria Janik-Czachor, R. P. Van Duyne^*

^*Corresponding author for this work

Chemistry

Research output: Contribution to journal › Article › peer-review

106 Scopus citations

Abstract

To date all surface enhanced Raman spectroscopy (SERS) studies have been carried out on rough metal surfaces. This has resulted in the general impression that surface roughness is an absolute prerequisite for the observation of SERS. In this paper we demonstrate, at least for the case of SERS at the solid-liquid interface (i.e., an electrochemical cell) that neither surface roughness (viz., quasi-spherical particles ≥ 250 Å in diameter) or electrochemical anodization are prerequisites to SERS observation. For the model system, Ag/0.05 M pyridine/0.1 M KCl/ H₂O, an enhancement factor of ca. 10⁴ is observed on "smooth", unanodized surfaces implying a maximum roughness contribution to the overall enhancement of only about ca. 10². The observation of SERS on "smooth" surfaces is not restricted to pyridine since it can also be observed in the system Ag/0.005 M Pt(CN)₄^2-/0.1 M SO₄^2-/H₂O. These results strongly support the hypothesis that the overall SERS enhancement of 10⁶ is the product of 10⁴ enhancement from a roughness independent mechanism (e.g., image-dipole mechanism) and a 10² enhancement from a roughness dependent mechanism (e.g., the development of geometrically defined electromagnetic resonances near rough solid surfaces - "lightning rod mechanism").

Original language	English (US)
Pages (from-to)	419-434
Number of pages	16
Journal	Surface Science
Volume	104
Issue number	2-3
DOIs	https://doi.org/10.1016/0039-6028(81)90069-8
State	Published - Mar 2 1981

Funding

We gratefully acknowledgef inancial support from the Office of Naval Research (Contract N00014-79-C-0794),a nd the National Science Foundation (Grant CHE-7824866).

ASJC Scopus subject areas

Condensed Matter Physics
Surfaces and Interfaces
Surfaces, Coatings and Films
Materials Chemistry

Access to Document

10.1016/0039-6028(81)90069-8

Cite this

@article{ea7e1b56a49a45cea96d6f222b68bbb9,

title = "Surface enhanced Raman spectroscopy: A re-examination of the role of surface roughness and electrochemical anodization",

abstract = "To date all surface enhanced Raman spectroscopy (SERS) studies have been carried out on rough metal surfaces. This has resulted in the general impression that surface roughness is an absolute prerequisite for the observation of SERS. In this paper we demonstrate, at least for the case of SERS at the solid-liquid interface (i.e., an electrochemical cell) that neither surface roughness (viz., quasi-spherical particles ≥ 250 {\AA} in diameter) or electrochemical anodization are prerequisites to SERS observation. For the model system, Ag/0.05 M pyridine/0.1 M KCl/ H2O, an enhancement factor of ca. 104 is observed on {"}smooth{"}, unanodized surfaces implying a maximum roughness contribution to the overall enhancement of only about ca. 102. The observation of SERS on {"}smooth{"} surfaces is not restricted to pyridine since it can also be observed in the system Ag/0.005 M Pt(CN)42-/0.1 M SO42-/H2O. These results strongly support the hypothesis that the overall SERS enhancement of 106 is the product of 104 enhancement from a roughness independent mechanism (e.g., image-dipole mechanism) and a 102 enhancement from a roughness dependent mechanism (e.g., the development of geometrically defined electromagnetic resonances near rough solid surfaces - {"}lightning rod mechanism{"}).",

author = "Schultz, {Steven G.} and Maria Janik-Czachor and {Van Duyne}, {R. P.}",

note = "Funding Information: We gratefully acknowledgef inancial support from the Office of Naval Research (Contract N00014-79-C-0794),a nd the National Science Foundation (Grant CHE-7824866).",

year = "1981",

month = mar,

day = "2",

doi = "10.1016/0039-6028(81)90069-8",

language = "English (US)",

volume = "104",

pages = "419--434",

journal = "Surface Science",

issn = "0039-6028",

publisher = "Elsevier B.V.",

number = "2-3",

}

TY - JOUR

T1 - Surface enhanced Raman spectroscopy

T2 - A re-examination of the role of surface roughness and electrochemical anodization

AU - Schultz, Steven G.

AU - Janik-Czachor, Maria

AU - Van Duyne, R. P.

N1 - Funding Information: We gratefully acknowledgef inancial support from the Office of Naval Research (Contract N00014-79-C-0794),a nd the National Science Foundation (Grant CHE-7824866).

PY - 1981/3/2

Y1 - 1981/3/2

N2 - To date all surface enhanced Raman spectroscopy (SERS) studies have been carried out on rough metal surfaces. This has resulted in the general impression that surface roughness is an absolute prerequisite for the observation of SERS. In this paper we demonstrate, at least for the case of SERS at the solid-liquid interface (i.e., an electrochemical cell) that neither surface roughness (viz., quasi-spherical particles ≥ 250 Å in diameter) or electrochemical anodization are prerequisites to SERS observation. For the model system, Ag/0.05 M pyridine/0.1 M KCl/ H2O, an enhancement factor of ca. 104 is observed on "smooth", unanodized surfaces implying a maximum roughness contribution to the overall enhancement of only about ca. 102. The observation of SERS on "smooth" surfaces is not restricted to pyridine since it can also be observed in the system Ag/0.005 M Pt(CN)42-/0.1 M SO42-/H2O. These results strongly support the hypothesis that the overall SERS enhancement of 106 is the product of 104 enhancement from a roughness independent mechanism (e.g., image-dipole mechanism) and a 102 enhancement from a roughness dependent mechanism (e.g., the development of geometrically defined electromagnetic resonances near rough solid surfaces - "lightning rod mechanism").

AB - To date all surface enhanced Raman spectroscopy (SERS) studies have been carried out on rough metal surfaces. This has resulted in the general impression that surface roughness is an absolute prerequisite for the observation of SERS. In this paper we demonstrate, at least for the case of SERS at the solid-liquid interface (i.e., an electrochemical cell) that neither surface roughness (viz., quasi-spherical particles ≥ 250 Å in diameter) or electrochemical anodization are prerequisites to SERS observation. For the model system, Ag/0.05 M pyridine/0.1 M KCl/ H2O, an enhancement factor of ca. 104 is observed on "smooth", unanodized surfaces implying a maximum roughness contribution to the overall enhancement of only about ca. 102. The observation of SERS on "smooth" surfaces is not restricted to pyridine since it can also be observed in the system Ag/0.005 M Pt(CN)42-/0.1 M SO42-/H2O. These results strongly support the hypothesis that the overall SERS enhancement of 106 is the product of 104 enhancement from a roughness independent mechanism (e.g., image-dipole mechanism) and a 102 enhancement from a roughness dependent mechanism (e.g., the development of geometrically defined electromagnetic resonances near rough solid surfaces - "lightning rod mechanism").

UR - http://www.scopus.com/inward/record.url?scp=0002230972&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0002230972&partnerID=8YFLogxK

U2 - 10.1016/0039-6028(81)90069-8

DO - 10.1016/0039-6028(81)90069-8

M3 - Article

AN - SCOPUS:0002230972

SN - 0039-6028

VL - 104

SP - 419

EP - 434

JO - Surface Science

JF - Surface Science

IS - 2-3

ER -

Surface enhanced Raman spectroscopy: A re-examination of the role of surface roughness and electrochemical anodization

Abstract

Funding

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this