Growth and properties of Au nanowires

Abstract

International audienceThe self assembling of Au nanoparticles into nanowires of different structure has been investigated by means of a periodic approach within density functional theory using a Au79 nanoparticle as building block. The density functional calculations show that the interaction of the Au nanoparticles takes place preferentially along the [111] direction, in agreement with experimental. The electronic structure of the different Au nanowires studied is found to be intermediate between that of the isolated nanoparticle and that of the bulk metal. This is perhaps not surprising but has important consequences for the chemistry of such nanostructures. Finally, calculations carried our for nanowires built from Cu, Ag and Au nanoparticles containing 38 atoms reveal that the self assembling mechanism is general but that the strength of the interaction is dictated by the chemical nature of the metal with Au being the coinage metal leading to stronger interaction between the nanoparticles

Stability and mobility of supported Nin (n = 1–10) clusters on ZrO2(111) and YSZ(111) surfaces: a density functional theory study

“…vertex and corners, accumulate electron density. 44 Thus, the Ni located at the vertex of the cluster could be a source of electrons for an eventual reaction with electron receptor molecules approaching the cluster from the gas phase. 50 Analysing the electron density difference between the cluster and the surface (Fig.…”

“…There are many possible shapes and adsorption sites for Ni n clusters. We have chosen the Ni n geometries based on the stability of fcc Ni surfaces [40][41][42][43] and small particles 44 to form triangular based structures in agreement with previous studies. We have therefore grown clusters exposing the Ni(111)-facet 45,46 on the ZrO 2 (111) and YSZ(111) surfaces, where the initial atomic spacing between the Ni atoms is 2.2 A, similar to the interatomic distance in the Ni(111) surface.…”

Role of Au−C Interactions on the Catalytic Activity of Au Nanoparticles Supported on TiC(001) toward Molecular Oxygen Dissociation

“…Because of the different size of the Au nanoparticles studied in the present work, it is necessary to use different supercells to simulate an adequate and comparable Au nanoparticle coverage and thus dispersion of supported particles while at the same time ensuring that the interaction between supported particles is negligible. , Thus, for Au 2 on TiC we used a 2 × 2 cubic unit cell containing a total of 66 (64 TiC + 2 Au) atoms and representing a coverage of 0.125 metal monolayers (ML) with respect to the number of Ti and C surface atoms. For supported Au 4 , we used a 3 × 3 unit cell (144 + 4 atoms) with a resulting coverage of 0.111 ML, whereas for supported Au 13 and Au 29 5 × 5 (400 + 13 atoms) and 6 × 6 (576 + 29 atoms) were employed, respectively, with coverage of 0.130 and 0.201 ML.…”

DFT-Assisted Spectroscopic Studies on the Coordination of Small Ligands to Palladium: From Isolated Ions to Nanoparticles

“…Despite this strong relationship between their structure and function, the practical applications and the performances of MNPs are still limited by the lack of a clear predictability of the synthesis outcome in terms of size and morphological dispersion. 5 , 6 …”

“…In the last decades, metal nanoparticles (MNPs) have been used increasingly as key components for applications in several fields such as energy conversion and storage, biomedicine and life science, electronics, information technology, and catalysis, thanks to their unique and fascinating properties. − Most of the physicochemical properties of MNPs (e.g., optical, catalytic, magnetic, and electronic properties) are highly dependent on a set of structural and morphological parameters, including composition, particle size, shape and exposure of facets, crystal structure, surface modification, and environment. Despite this strong relationship between their structure and function, the practical applications and the performances of MNPs are still limited by the lack of a clear predictability of the synthesis outcome in terms of size and morphological dispersion. , …”