Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanisms
- Autores
- Gimeno, Y.; Hernández Creus, A.; Carro, P.; González, S.; Salvarezza, Roberto Carlos; Arvia, Alejandro Jorge
- Año de publicación
- 2002
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- Scanning tunneling microscopy (STM) and conventional electrochemical techniques were utilized to investigate the growth kinetics and mechanism of palladium island electroformation on highly oriented pyrolitic graphite (HOPG) from aqueous acid palladium chloride solutions at 298 K. Initially, the electrodeposition reaction at low cathodic overpotentials involves an activation process in which a PdCl2 surface intermediate is formed. At intermediate overpotentials, the growth of palladium islands involves a progressive nucleation and growth model under diffusion control, whereas at high overpotentials, the bulk discharge of soluble palladium species undergoes a free convective-diffusion process. As the cathodic overpotential is shifted negatively, the aspect ratio of the islands, defined as the ratio of the maximum height of the island to the island radius, and the island size decrease, whereas the island density increases. As the cathodic overpotential becomes a few millivolts more positive than the threshold potential of the hydrogen evolution reaction, the island shape changes from a compact disk to a quasi-2D dense radial Pd(111) island. The formation of a dense radial morphology and its small departure from a perfect 2D pattern indicates the presence of weak step-edge energy barriers, as expected from theoretical calculations for Pd(111). These results stress the key role of step-edge energy barriers in determining growth patterns during metal electrodeposition.
Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas
Facultad de Ciencias Exactas - Materia
-
Ciencias Exactas
Química
scanning tunneling microscopy
Electroquímica
Paladio
Cinética química
electroformation
Técnicas Electroquímicas - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- http://creativecommons.org/licenses/by-nc-sa/4.0/
- Repositorio
- Institución
- Universidad Nacional de La Plata
- OAI Identificador
- oai:sedici.unlp.edu.ar:10915/83728
Ver los metadatos del registro completo
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Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanismsGimeno, Y.Hernández Creus, A.Carro, P.González, S.Salvarezza, Roberto CarlosArvia, Alejandro JorgeCiencias ExactasQuímicascanning tunneling microscopyElectroquímicaPaladioCinética químicaelectroformationTécnicas ElectroquímicasScanning tunneling microscopy (STM) and conventional electrochemical techniques were utilized to investigate the growth kinetics and mechanism of palladium island electroformation on highly oriented pyrolitic graphite (HOPG) from aqueous acid palladium chloride solutions at 298 K. Initially, the electrodeposition reaction at low cathodic overpotentials involves an activation process in which a PdCl<sub>2</sub> surface intermediate is formed. At intermediate overpotentials, the growth of palladium islands involves a progressive nucleation and growth model under diffusion control, whereas at high overpotentials, the bulk discharge of soluble palladium species undergoes a free convective-diffusion process. As the cathodic overpotential is shifted negatively, the aspect ratio of the islands, defined as the ratio of the maximum height of the island to the island radius, and the island size decrease, whereas the island density increases. As the cathodic overpotential becomes a few millivolts more positive than the threshold potential of the hydrogen evolution reaction, the island shape changes from a compact disk to a quasi-2D dense radial Pd(111) island. The formation of a dense radial morphology and its small departure from a perfect 2D pattern indicates the presence of weak step-edge energy barriers, as expected from theoretical calculations for Pd(111). These results stress the key role of step-edge energy barriers in determining growth patterns during metal electrodeposition.Instituto de Investigaciones Fisicoquímicas Teóricas y AplicadasFacultad de Ciencias Exactas2002-04-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf4232-4244http://sedici.unlp.edu.ar/handle/10915/83728enginfo:eu-repo/semantics/altIdentifier/issn/1520-6106info:eu-repo/semantics/altIdentifier/doi/10.1021/jp014176einfo:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-sa/4.0/Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:15:55Zoai:sedici.unlp.edu.ar:10915/83728Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:15:55.724SEDICI (UNLP) - Universidad Nacional de La Platafalse |
dc.title.none.fl_str_mv |
Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanisms |
title |
Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanisms |
spellingShingle |
Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanisms Gimeno, Y. Ciencias Exactas Química scanning tunneling microscopy Electroquímica Paladio Cinética química electroformation Técnicas Electroquímicas |
title_short |
Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanisms |
title_full |
Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanisms |
title_fullStr |
Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanisms |
title_full_unstemmed |
Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanisms |
title_sort |
Electrochemical formation of palladium islands on HOPG: Kinetics, morphology, and growth mechanisms |
dc.creator.none.fl_str_mv |
Gimeno, Y. Hernández Creus, A. Carro, P. González, S. Salvarezza, Roberto Carlos Arvia, Alejandro Jorge |
author |
Gimeno, Y. |
author_facet |
Gimeno, Y. Hernández Creus, A. Carro, P. González, S. Salvarezza, Roberto Carlos Arvia, Alejandro Jorge |
author_role |
author |
author2 |
Hernández Creus, A. Carro, P. González, S. Salvarezza, Roberto Carlos Arvia, Alejandro Jorge |
author2_role |
author author author author author |
dc.subject.none.fl_str_mv |
Ciencias Exactas Química scanning tunneling microscopy Electroquímica Paladio Cinética química electroformation Técnicas Electroquímicas |
topic |
Ciencias Exactas Química scanning tunneling microscopy Electroquímica Paladio Cinética química electroformation Técnicas Electroquímicas |
dc.description.none.fl_txt_mv |
Scanning tunneling microscopy (STM) and conventional electrochemical techniques were utilized to investigate the growth kinetics and mechanism of palladium island electroformation on highly oriented pyrolitic graphite (HOPG) from aqueous acid palladium chloride solutions at 298 K. Initially, the electrodeposition reaction at low cathodic overpotentials involves an activation process in which a PdCl<sub>2</sub> surface intermediate is formed. At intermediate overpotentials, the growth of palladium islands involves a progressive nucleation and growth model under diffusion control, whereas at high overpotentials, the bulk discharge of soluble palladium species undergoes a free convective-diffusion process. As the cathodic overpotential is shifted negatively, the aspect ratio of the islands, defined as the ratio of the maximum height of the island to the island radius, and the island size decrease, whereas the island density increases. As the cathodic overpotential becomes a few millivolts more positive than the threshold potential of the hydrogen evolution reaction, the island shape changes from a compact disk to a quasi-2D dense radial Pd(111) island. The formation of a dense radial morphology and its small departure from a perfect 2D pattern indicates the presence of weak step-edge energy barriers, as expected from theoretical calculations for Pd(111). These results stress the key role of step-edge energy barriers in determining growth patterns during metal electrodeposition. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas Facultad de Ciencias Exactas |
description |
Scanning tunneling microscopy (STM) and conventional electrochemical techniques were utilized to investigate the growth kinetics and mechanism of palladium island electroformation on highly oriented pyrolitic graphite (HOPG) from aqueous acid palladium chloride solutions at 298 K. Initially, the electrodeposition reaction at low cathodic overpotentials involves an activation process in which a PdCl<sub>2</sub> surface intermediate is formed. At intermediate overpotentials, the growth of palladium islands involves a progressive nucleation and growth model under diffusion control, whereas at high overpotentials, the bulk discharge of soluble palladium species undergoes a free convective-diffusion process. As the cathodic overpotential is shifted negatively, the aspect ratio of the islands, defined as the ratio of the maximum height of the island to the island radius, and the island size decrease, whereas the island density increases. As the cathodic overpotential becomes a few millivolts more positive than the threshold potential of the hydrogen evolution reaction, the island shape changes from a compact disk to a quasi-2D dense radial Pd(111) island. The formation of a dense radial morphology and its small departure from a perfect 2D pattern indicates the presence of weak step-edge energy barriers, as expected from theoretical calculations for Pd(111). These results stress the key role of step-edge energy barriers in determining growth patterns during metal electrodeposition. |
publishDate |
2002 |
dc.date.none.fl_str_mv |
2002-04-01 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Articulo http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
format |
article |
status_str |
publishedVersion |
dc.identifier.none.fl_str_mv |
http://sedici.unlp.edu.ar/handle/10915/83728 |
url |
http://sedici.unlp.edu.ar/handle/10915/83728 |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/issn/1520-6106 info:eu-repo/semantics/altIdentifier/doi/10.1021/jp014176e |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) |
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openAccess |
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