Why Citrate Shapes Tetrahedral and Octahedral Colloidal Platinum Nanoparticles in Water
Autor: | Enrique Herrero, Juan M. Feliu, José M. Gisbert-González, Adolfo Ferre-Vilaplana |
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Přispěvatelé: | Universidad de Alicante. Departamento de Química Física, Universidad de Alicante. Instituto Universitario de Electroquímica, Electroquímica de Superficies |
Rok vydání: | 2018 |
Předmět: |
Colloidal platinum nanoparticles
Materials science Nanoparticle Shape Water 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology Platinum nanoparticles 01 natural sciences 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials Crystallography General Energy Octahedron Tetrahedron Química Física Physical and Theoretical Chemistry 0210 nano-technology LENGUAJES Y SISTEMAS INFORMATICOS Citrate |
Zdroj: | RUA. Repositorio Institucional de la Universidad de Alicante Universidad de Alicante (UA) RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia instname |
Popis: | [EN] The performance of many advanced catalytic systems depends not only on the size and composition but also on the specific shape of the metal nanoparticles (NPs) from which they are assembled. In turn, the shape of colloidal NPs depends on the specific capping agent involved in their synthesis, though the mechanism is still poorly understood. Here, supported by electrochemical experiments, Fourier transform infrared spectra, and density functional theory calculations, on well-defined surfaces, we show how a specific capping agent determines the shape of colloidal NPs. Solvated citrate can become simultaneously adsorbed on the Pt(111) surface through three dehydrogenated carboxylic groups, with each one of them in bidentate configuration. On the other two basal planes, citrate can be adsorbed through only two of them. For this reason, under the synthesis conditions, citrate is more favorably adsorbed on the Pt(111) than on the other two basal planes of platinum. This adsorption behavior explains why colloidal platinum NPs of tetrahedral and octahedral shape are produced when citrate is used as the capping agent in water. The mechanism for citrate would also determine the shape of other pure face-centered cubic metals and can inspire the engineering of future capping agents. This work has been financially supported by the MCINN-FEDER (Spain) through project CTQ2016-76221-P. |
Databáze: | OpenAIRE |
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