New insight into the electrochemical desorption of alkanethiol SAMs on gold

A combination of Polarization Modulation Infrared Reflection Absorption Spectroscopy (PMIRRAS) under electrochemical control, Electrochemical Scanning Tunneling Microscopy (ECSTM) and Molecular Dynamics (MD) simulations has been used to shed light on the reductive desorption process of dodecanethiol...

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Detalles Bibliográficos
Autores principales: Grumelli, Doris E., Mendez De Leo, Lucila Paula
Publicado: 2012
Materias:
alkane
gold
thiol derivative
water
adsorption
article
chemistry
electrochemical analysis
molecular dynamics
surface property
Adsorption
Alkanes
Electrochemical Techniques
Gold
Molecular Dynamics Simulation
Sulfhydryl Compounds
Surface Properties
Water
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14639076_v14_n35_p12355_Pensa
http://hdl.handle.net/20.500.12110/paper_14639076_v14_n35_p12355_Pensa
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id paper:paper_14639076_v14_n35_p12355_Pensa
record_format dspace
spelling paper:paper_14639076_v14_n35_p12355_Pensa2023-06-08T16:16:25Z New insight into the electrochemical desorption of alkanethiol SAMs on gold Grumelli, Doris E. Mendez De Leo, Lucila Paula alkane gold thiol derivative water adsorption article chemistry electrochemical analysis molecular dynamics surface property Adsorption Alkanes Electrochemical Techniques Gold Molecular Dynamics Simulation Sulfhydryl Compounds Surface Properties Water A combination of Polarization Modulation Infrared Reflection Absorption Spectroscopy (PMIRRAS) under electrochemical control, Electrochemical Scanning Tunneling Microscopy (ECSTM) and Molecular Dynamics (MD) simulations has been used to shed light on the reductive desorption process of dodecanethiol (C12) and octadecanethiol (C18) SAMs on gold in aqueous electrolytes. Experimental PMIRRAS, ECSTM and MD simulations data for C12 desorption are consistent with formation of randomly distributed micellar aggregates stabilized by Na + ions, coexisting with a lying-down phase of molecules. The analysis of pit and Au island coverage before and after desorption is consistent with the thiolate-Au adatoms models. On the other hand, PMIRRAS and MD data for C18 indicate that the desorbed alkanethiolates adopt a Na+ ion-stabilized bilayer of interdigitated alkanethiolates, with no evidence of lying down molecules. MD simulations also show that both the degree of order and tilt angle of the desorbed alkanethiolates change with the surface charge on the metal, going from bilayers to micelles. These results demonstrate the complexity of the alkanethiol desorption in the presence of water and the fact that chain length and counterions play a key role in a complex structure. © This journal is the Owner Societies 2012. Fil:Grumelli, D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Méndez De Leo, L.P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2012 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14639076_v14_n35_p12355_Pensa http://hdl.handle.net/20.500.12110/paper_14639076_v14_n35_p12355_Pensa
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic alkane
gold
thiol derivative
water
adsorption
article
chemistry
electrochemical analysis
molecular dynamics
surface property
Adsorption
Alkanes
Electrochemical Techniques
Gold
Molecular Dynamics Simulation
Sulfhydryl Compounds
Surface Properties
Water
spellingShingle alkane
gold
thiol derivative
water
adsorption
article
chemistry
electrochemical analysis
molecular dynamics
surface property
Adsorption
Alkanes
Electrochemical Techniques
Gold
Molecular Dynamics Simulation
Sulfhydryl Compounds
Surface Properties
Water
Grumelli, Doris E.
Mendez De Leo, Lucila Paula
New insight into the electrochemical desorption of alkanethiol SAMs on gold
topic_facet alkane
gold
thiol derivative
water
adsorption
article
chemistry
electrochemical analysis
molecular dynamics
surface property
Adsorption
Alkanes
Electrochemical Techniques
Gold
Molecular Dynamics Simulation
Sulfhydryl Compounds
Surface Properties
Water
description A combination of Polarization Modulation Infrared Reflection Absorption Spectroscopy (PMIRRAS) under electrochemical control, Electrochemical Scanning Tunneling Microscopy (ECSTM) and Molecular Dynamics (MD) simulations has been used to shed light on the reductive desorption process of dodecanethiol (C12) and octadecanethiol (C18) SAMs on gold in aqueous electrolytes. Experimental PMIRRAS, ECSTM and MD simulations data for C12 desorption are consistent with formation of randomly distributed micellar aggregates stabilized by Na + ions, coexisting with a lying-down phase of molecules. The analysis of pit and Au island coverage before and after desorption is consistent with the thiolate-Au adatoms models. On the other hand, PMIRRAS and MD data for C18 indicate that the desorbed alkanethiolates adopt a Na+ ion-stabilized bilayer of interdigitated alkanethiolates, with no evidence of lying down molecules. MD simulations also show that both the degree of order and tilt angle of the desorbed alkanethiolates change with the surface charge on the metal, going from bilayers to micelles. These results demonstrate the complexity of the alkanethiol desorption in the presence of water and the fact that chain length and counterions play a key role in a complex structure. © This journal is the Owner Societies 2012.
author Grumelli, Doris E.
Mendez De Leo, Lucila Paula
author_facet Grumelli, Doris E.
Mendez De Leo, Lucila Paula
author_sort Grumelli, Doris E.
title New insight into the electrochemical desorption of alkanethiol SAMs on gold
title_short New insight into the electrochemical desorption of alkanethiol SAMs on gold
title_full New insight into the electrochemical desorption of alkanethiol SAMs on gold
title_fullStr New insight into the electrochemical desorption of alkanethiol SAMs on gold
title_full_unstemmed New insight into the electrochemical desorption of alkanethiol SAMs on gold
title_sort new insight into the electrochemical desorption of alkanethiol sams on gold
publishDate 2012
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14639076_v14_n35_p12355_Pensa
http://hdl.handle.net/20.500.12110/paper_14639076_v14_n35_p12355_Pensa
work_keys_str_mv AT grumellidorise newinsightintotheelectrochemicaldesorptionofalkanethiolsamsongold
AT mendezdeleolucilapaula newinsightintotheelectrochemicaldesorptionofalkanethiolsamsongold
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