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The Theory of Surface-Enhanced Raman Spectroscopy on Organic Semiconductors: Graphene
Drawing on a theoretical expression previously derived for general semiconductor substrates, we examine the surface-enhancement of the Raman signal (SERS) when the substrate is chosen to be monolayer graphene. The underlying theory involves vibronic coupling, originally proposed by Herzberg and Tell...
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Formato: | Online Artículo Texto |
Lenguaje: | English |
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MDPI
2022
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9415012/ https://www.ncbi.nlm.nih.gov/pubmed/36014602 http://dx.doi.org/10.3390/nano12162737 |
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author | Lombardi, John R. |
author_facet | Lombardi, John R. |
author_sort | Lombardi, John R. |
collection | PubMed |
description | Drawing on a theoretical expression previously derived for general semiconductor substrates, we examine the surface-enhancement of the Raman signal (SERS) when the substrate is chosen to be monolayer graphene. The underlying theory involves vibronic coupling, originally proposed by Herzberg and Teller. Vibronic coupling of the allowed molecular transitions with the charge-transfer transitions between the molecule and the substrate has been shown to be responsible for the SERS enhancement in semiconductor substrates. We then examine such an expression for the Raman enhancement in monolayer graphene, which is dependent on the square of the derivative of the density of states of the graphene. On integration, we find that the discontinuity of the density-of-states function leads to a singularity in the SERS intensity. Knowledge of the location of this resonance allows us to maximize the Raman intensity by careful alignment of the doping level of the graphene substrate with the charge-transfer transition. |
format | Online Article Text |
id | pubmed-9415012 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2022 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-94150122022-08-27 The Theory of Surface-Enhanced Raman Spectroscopy on Organic Semiconductors: Graphene Lombardi, John R. Nanomaterials (Basel) Article Drawing on a theoretical expression previously derived for general semiconductor substrates, we examine the surface-enhancement of the Raman signal (SERS) when the substrate is chosen to be monolayer graphene. The underlying theory involves vibronic coupling, originally proposed by Herzberg and Teller. Vibronic coupling of the allowed molecular transitions with the charge-transfer transitions between the molecule and the substrate has been shown to be responsible for the SERS enhancement in semiconductor substrates. We then examine such an expression for the Raman enhancement in monolayer graphene, which is dependent on the square of the derivative of the density of states of the graphene. On integration, we find that the discontinuity of the density-of-states function leads to a singularity in the SERS intensity. Knowledge of the location of this resonance allows us to maximize the Raman intensity by careful alignment of the doping level of the graphene substrate with the charge-transfer transition. MDPI 2022-08-09 /pmc/articles/PMC9415012/ /pubmed/36014602 http://dx.doi.org/10.3390/nano12162737 Text en © 2022 by the author. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Lombardi, John R. The Theory of Surface-Enhanced Raman Spectroscopy on Organic Semiconductors: Graphene |
title | The Theory of Surface-Enhanced Raman Spectroscopy on Organic Semiconductors: Graphene |
title_full | The Theory of Surface-Enhanced Raman Spectroscopy on Organic Semiconductors: Graphene |
title_fullStr | The Theory of Surface-Enhanced Raman Spectroscopy on Organic Semiconductors: Graphene |
title_full_unstemmed | The Theory of Surface-Enhanced Raman Spectroscopy on Organic Semiconductors: Graphene |
title_short | The Theory of Surface-Enhanced Raman Spectroscopy on Organic Semiconductors: Graphene |
title_sort | theory of surface-enhanced raman spectroscopy on organic semiconductors: graphene |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9415012/ https://www.ncbi.nlm.nih.gov/pubmed/36014602 http://dx.doi.org/10.3390/nano12162737 |
work_keys_str_mv | AT lombardijohnr thetheoryofsurfaceenhancedramanspectroscopyonorganicsemiconductorsgraphene AT lombardijohnr theoryofsurfaceenhancedramanspectroscopyonorganicsemiconductorsgraphene |