Differences in intermediate structures and electronic states associated with oxygen adsorption onto Pt, Cu, and Au clusters as oxygen reduction catalysts
| Autor: | Junko Hieda, Maria Antoaneta Bratescu, Tetsunori Morishita, Nagahiro Saito, Tomonaga Ueno, Gasidit Panomsuwan |
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| Rok vydání: | 2016 |
| Předmět: |
Acoustics and Ultrasonics
Chemistry Inorganic chemistry Fermi level Ab initio 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics Antibonding molecular orbital 01 natural sciences 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials Catalysis Crystallography symbols.namesake Adsorption Desorption symbols Cluster (physics) Molecular orbital 0210 nano-technology |
| Zdroj: | Journal of Physics D: Applied Physics. 49:415305 |
| ISSN: | 1361-6463 0022-3727 |
| DOI: | 10.1088/0022-3727/49/41/415305 |
| Popis: | We used ab initio molecular orbital (MO) calculations to study the differences in the intermediate structures and the electronic states involved in the adsorption of O2 onto 13-atom metal clusters of Pt, Cu, and Au. Additionally, the conditions required for the electrocatalytic oxygen reduction reaction (ORR) on the Pt, Cu, and Au clusters were investigated and discussed. The intermediates involved in O2 adsorption onto Pt, Cu, and Au were found to be (Pt–O)–(Pt–O), Cu–O, and Au–O2, respectively. The differences in the O2 adsorption intermediates is explained on the basis of our analysis of the projected density of state (PDOS) area of the new MOs produced from a mixture of the 2pπ * orbitals of O2 and the d orbitals of the metal clusters. The formation of the (Pt–O)–(Pt–O) intermediate after the adsorption of O2 onto the Pt cluster is attributed to the emergence of an antibonding orbital above the Fermi level. Thus, this electronic state can lead to the decomposition and desorption of O2 molecules, thereby promoting the high-activity level of ORR. For the Cu cluster, a new antibonding orbital was observed below the Fermi level. Moreover, the Cu cluster surface can only promote O2 decomposition and not O2 desorption due to the formation of copper oxides. For the Au cluster, no new MOs related to 2pπ * orbitals of O2 appeared because O2 was molecularly adsorbed, implying that the Au cluster is an inefficient ORR catalyst. |
| Databáze: | OpenAIRE |
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