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

• Autor(a) principal: Ângelo, Antônio Carlos D. [UNESP]
• Data de Publicação: 2001
• Outros Autores: De Souza, Aguinaldo R. [UNESP], Morgon, Nelson H., Sambrano, Júlio R. [UNESP]
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/224456
• topic: ab initio; Adsorption; Cyclic voltammetry; DFT; Hydrogen; Sulfide

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.