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Expansion of interatomic distances in platinum catalyst nanoparticles / K. Du in Acta materialia, Vol. 58 N° 3 (Fevrier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 836-845 Titre : Expansion of interatomic distances in platinum catalyst nanoparticles Type de document : texte imprimé Auteurs : K. Du, Auteur ; F. Ernst, Auteur ; M. C. Pelsozy, Auteur Article en page(s) : pp. 836-845 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Nanoparticles  Catalysts  Atomistic  structure  Quantitative  high-resolution  transmission  electron  microscopy  Spherical-aberration-adjusted  transmission  electron  microscopy Index. décimale : 669 Métallurgie Résumé : We study the atomistic structure of Pt catalyst nanoparticles using HRTEM (high-resolution transmission electron microscopy). The particles exhibit a faceted, cubo-octahedral shape, extended planar defects, and mono-atomic surface steps. HRTEM imaging with negative spherical aberration yielded atomic-resolution images with a minimum of artifacts. Combining digital image processing, quantitative image analysis, and HRTEM image simulations to determine local variations of the spacing between neighboring Pt atom columns, we have found an expansion of the lattice parameter in the particle core and even larger, locally varying expansion of Pt–Pt next-neighbor distances at the particle surface. The latter likely originates from an amorphous oxide on the nanoparticle surface and/or dissolution of oxygen on subsurface sites. These structural features may significantly impact the catalytic activity of Pt nanoparticles. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235556%23 [...] [article] Expansion of interatomic distances in platinum catalyst nanoparticles [texte imprimé] / K. Du, Auteur ; F. Ernst, Auteur ; M. C. Pelsozy, Auteur . - pp. 836-845. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 836-845 Mots-clés : Nanoparticles  Catalysts  Atomistic  structure  Quantitative  high-resolution  transmission  electron  microscopy  Spherical-aberration-adjusted  transmission  electron  microscopy Index. décimale : 669 Métallurgie Résumé : We study the atomistic structure of Pt catalyst nanoparticles using HRTEM (high-resolution transmission electron microscopy). The particles exhibit a faceted, cubo-octahedral shape, extended planar defects, and mono-atomic surface steps. HRTEM imaging with negative spherical aberration yielded atomic-resolution images with a minimum of artifacts. Combining digital image processing, quantitative image analysis, and HRTEM image simulations to determine local variations of the spacing between neighboring Pt atom columns, we have found an expansion of the lattice parameter in the particle core and even larger, locally varying expansion of Pt–Pt next-neighbor distances at the particle surface. The latter likely originates from an amorphous oxide on the nanoparticle surface and/or dissolution of oxygen on subsurface sites. These structural features may significantly impact the catalytic activity of Pt nanoparticles. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235556%23 [...]

Expansion of interatomic distances in platinum catalyst nanoparticles / K. Du in Acta materialia, Vol. 58 N° 3 (Fevrier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 836–845 Titre : Expansion of interatomic distances in platinum catalyst nanoparticles Type de document : texte imprimé Auteurs : K. Du, Auteur ; F. Ernst, Auteur ; M. C. Pelsozy, Auteur Année de publication : 2011 Article en page(s) : pp. 836–845 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Nanoparticles  Catalysts  Atomistic  structure  Quantitative  high-resolution  transmission  electron  microscopy  Spherical-aberration-adjusted  transmission  electron  microscopy Résumé : We study the atomistic structure of Pt catalyst nanoparticles using HRTEM (high-resolution transmission electron microscopy). The particles exhibit a faceted, cubo-octahedral shape, extended planar defects, and mono-atomic surface steps. HRTEM imaging with negative spherical aberration yielded atomic-resolution images with a minimum of artifacts. Combining digital image processing, quantitative image analysis, and HRTEM image simulations to determine local variations of the spacing between neighboring Pt atom columns, we have found an expansion of the lattice parameter in the particle core and even larger, locally varying expansion of Pt–Pt next-neighbor distances at the particle surface. The latter likely originates from an amorphous oxide on the nanoparticle surface and/or dissolution of oxygen on subsurface sites. These structural features may significantly impact the catalytic activity of Pt nanoparticles. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409006673 [article] Expansion of interatomic distances in platinum catalyst nanoparticles [texte imprimé] / K. Du, Auteur ; F. Ernst, Auteur ; M. C. Pelsozy, Auteur . - 2011 . - pp. 836–845. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 836–845 Mots-clés : Nanoparticles  Catalysts  Atomistic  structure  Quantitative  high-resolution  transmission  electron  microscopy  Spherical-aberration-adjusted  transmission  electron  microscopy Résumé : We study the atomistic structure of Pt catalyst nanoparticles using HRTEM (high-resolution transmission electron microscopy). The particles exhibit a faceted, cubo-octahedral shape, extended planar defects, and mono-atomic surface steps. HRTEM imaging with negative spherical aberration yielded atomic-resolution images with a minimum of artifacts. Combining digital image processing, quantitative image analysis, and HRTEM image simulations to determine local variations of the spacing between neighboring Pt atom columns, we have found an expansion of the lattice parameter in the particle core and even larger, locally varying expansion of Pt–Pt next-neighbor distances at the particle surface. The latter likely originates from an amorphous oxide on the nanoparticle surface and/or dissolution of oxygen on subsurface sites. These structural features may significantly impact the catalytic activity of Pt nanoparticles. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409006673