Theoretical Study of Hydrogen Adsorption on Au@Pd Icosahedral Nanoparticle
| Autor: | Mario German Sandoval, Graciela Petra Brizuela, Caetano R. Miranda, Aline O. Pereira, Paula Verónica Jasen, Roman Jorge Luna |
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| Rok vydání: | 2017 |
| Předmět: |
Hydrogen
Ciencias Físicas Nanoparticle chemistry.chemical_element 02 engineering and technology Otras Ciencias Físicas 010402 general chemistry DFT 01 natural sciences Dissociation (chemistry) Catalysis Adsorption Computational chemistry Molecule Work function Physical and Theoretical Chemistry Au@Pd NANOPARTICLES CATALYSIS Chemistry HYDROGEN 021001 nanoscience & nanotechnology 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials General Energy Physical chemistry Density functional theory 0210 nano-technology CIENCIAS NATURALES Y EXACTAS |
| Zdroj: | The Journal of Physical Chemistry C. 121:8613-8622 |
| ISSN: | 1932-7455 1932-7447 |
| DOI: | 10.1021/acs.jpcc.7b00286 |
| Popis: | First-principles calculations based on the density functional theory (DFT) were applied to study the H2 adsorption on Au@Pd NP (core@shell icosahedral bimetallic nanoparticle). The calculations indicate that, for almost all adsorption sites, there is no energy barrier for H2 dissociation at the surface of Au@Pd NP, and the H2 molecule spontaneously dissociates. The only exceptions are the case of atop from edge (AE) and atop from vertex (AV) sites, where there is no dissociation at all. Looking at the adsorption energies, dissociated cases are 1.3 eV more stable than nondissociated cases. The work function (WF) values associated with NP with H2 adsorbed are lower than that obtained in the case of the Pd/Au(111) surface. When H2 is dissociated on the NP or surface, the WF increases, while in the nondissociated case it decreases. We also considered the changes in hydrogen adsorption and dissociation in mixed shell NP structures. The atomic H penetration was also studied for Au@Pd NP. Hydrogen adsorption on both Au@Pd NP and Pd/Au(111) surface systems leads to a slight shift of Pd's d states to lower energies, while the s and p states are almost unaffected. A higher hybridization between Pd and H is detected in the NP case. Each H atom of the H2 molecule adsorbed on the NP becomes negatively charged. It seems that the charge transference occurs toward the NP. The bond order on orbital population analysis indicates no bond for H-H and a decrease in the metal-metal bond while a Pd-H bond is formed. (Figure Presented). Fil: Sandoval, Mario German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina Fil: Luna, Roman Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina Fil: Brizuela, Graciela Petra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina Fil: Pereira, Aline O.. Universidade Federal do ABC; Brasil Fil: Miranda, C. R.. Universidade de Sao Paulo; Brasil Fil: Jasen, Paula Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina |
| Databáze: | OpenAIRE |
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