Estudo da adsorção de hidrogênio e sulfeto na superfície de paládio: Aspectos experimentais (eletroquímica) e teóricos (ab initio e teoria do funcional da densidade)

The adsorption of H and S2- species on Pd (100) has been studied with ab initio, density-functional calculations and electrochemical methods. A cluster of five Pd atoms with a frozen geometry described the surface. The computational calculations were performed through the GAUSSIAN94 program, and the...

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Detalles Bibliográficos
Autores: Ângelo, Antônio Carlos D. [UNESP], De Souza, Aguinaldo R. [UNESP], Morgon, Nelson H., Sambrano, Júlio R. [UNESP]
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2001
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:portugués
OAI Identifier:oai:repositorio.unesp.br:11449/224456
Acceso en línea:http://hdl.handle.net/11449/224456
Access Level:acceso abierto
Palabra clave:ab initio
Adsorption
Cyclic voltammetry
DFT
Hydrogen
Sulfide
Descripción
Sumario:The adsorption of H and S2- species on Pd (100) has been studied with ab initio, density-functional calculations and electrochemical methods. A cluster of five Pd atoms with a frozen geometry described the surface. The computational calculations were performed through the GAUSSIAN94 program, and the basis functions adapted to a pseudo-potential obtained by using the Generator Coordinate Method adapted to the this program. Using the cyclic voltammetry technique through a Model 283 Potentiostat/Galvanostat E.G.&G-PAR obtained the electrochemical results. The calculated chemisorption geometry has a Pd-H distance of 1.55Å, and the potential energy surface was calculated using the Becke3P86//(GCM/DFT/SBK) methodology. The adsorption of S2- ions on Pd surface obtained both through comparison between the experimental and theoretical results, at MP2 level, suggest a S2- absorption into the metallic cluster. The produced Pd-(S2-) system was show to be very stable under the employed experimental conditions. The paper has shows the powerful aid of computational methods to interpret adsorption experimental data.