Structural order in ultrathin films of the monolayer protected clusters based upon 4 nm gold nanocrystals: an experimental and theoretical study
| Autor: | Bhattarai, Nabraj, Khanal, Subarna, Bahena, Daniel, Olmos Asar, Jimena Anahí, Ponce, Arturo, Whetten, Robert L., Mariscal, Marcelo, Yacaman, Miguel Jose |
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| Přispěvatelé: | Bhattarai, Nabraj, Khanal, Subarna, Bahena, Daniel, OLMOS ASAR, Jimena Anahi, Ponce, Arturo, Whetten, Robert L., Mariscal, Marcelo M., Jose Yacaman, Miguel |
| Rok vydání: | 2014 |
| Předmět: |
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Molecular Materials science Superlattice General Physics and Astronomy Metal Nanoparticles Article Nanocomposites purl.org/becyt/ford/1 [https] Lattice constant nanocrystals Monolayer Materials Testing purl.org/becyt/ford/1.4 [https] Computer Simulation clusters Physical and Theoretical Chemistry Particle Size Otras Ciencias Químicas clusters nanocrystals nanoparticles Ciencias Químicas Membranes Artificial Crystallography Electron diffraction Nanocrystal Models Chemical Transmission electron microscopy Colloidal gold Grain boundary nanoparticles Gold GOLD NANOCRYSTALS Crystallization CIENCIAS NATURALES Y EXACTAS MONOLAYER PROTECTED CLUSTERS |
| Zdroj: | CONICET Digital (CONICET) Consejo Nacional de Investigaciones Científicas y Técnicas instacron:CONICET |
| ISSN: | 1463-9084 |
| Popis: | The structural order in ultrathin films of monolayer protected clusters (MPCs) is important in a number of application areas but can be difficult to demonstrate by conventional methods, particularly when the metallic core dimension, d, is in the intermediate size-range, 1.5 < d < 5.0 nm. Here, improved techniques for the synthesis of monodisperse thiolate-protected gold nanoparticles have made possible the production of dodecane-thiolate saturated ∼4 ± 0.5 nm Au clusters with single-crystal core structure and morphology. An ultrathin ordered film or superlattice of these nanocrystal-core MPCs is prepared and investigated using aberration corrected scanning/transmission electron microscopy (STEM) which allowed imaging of long-range hexagonally ordered superlattices of the nanocrystals, separated by the thiolate groups. The lattice constants determined by direct imaging are in good agreement with those determined by small-angle electron diffraction. The STEM image revealed the characteristic grain boundary (GB) with sigma (Σ) 13 in the interface between two crystals. The formation and structures found are interpreted on the basis of theoretical calculations employing molecular dynamics (MD) simulations and coarse-grained (CG) approach. The structural order in ultrathin films of monolayer protected clusters (MPCs) is important in a number of application areas but can be difficult to demonstrate by conventional methods, particularly when the metallic core dimension, d, is in the intermediate size-range, 1.5 < d < 5.0 nm. Here, improved techniques for the synthesis of monodisperse thiolate-protected gold nanoparticles have made possible the production of dodecane-thiolate saturated ∼4 ± 0.5 nm Au clusters with single-crystal core structure and morphology. An ultrathin ordered film or superlattice of these nanocrystal-core MPCs is prepared and investigated using aberration corrected scanning/transmission electron microscopy (STEM) which allowed imaging of long-range hexagonally ordered superlattices of the nanocrystals, separated by the thiolate groups. The lattice constants determined by direct imaging are in good agreement with those determined by small-angle electron diffraction. The STEM image revealed the characteristic grain boundary (GB) with sigma (Σ) 13 in the interface between two crystals. The formation and structures found are interpreted on the basis of theoretical calculations employing molecular dynamics (MD) simulations and coarse-grained (CG) approach. Fil: Bhattarai, Nabraj. University of Texas at San Antonio; Estados Unidos Fil: Bhattarai, Nabraj. University of Texas at San Antonio; Estados Unidos Fil: Khanal, Subarna. University of Texas at San Antonio; Estados Unidos Fil: Khanal, Subarna. University of Texas at San Antonio; Estados Unidos Fil: Bahena, Daniel. University of Texas at San Antonio; Estados Unidos Fil: Bahena, Daniel. University of Texas at San Antonio; Estados Unidos Fil: Olmos Asar, Jimena Anahí. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina. Università degli Studi di Trieste; Italia Fil: Olmos Asar, Jimena Anahí. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina. Università degli Studi di Trieste; Italia Fil: Ponce, Arturo. University of Texas at San Antonio; Estados Unidos Fil: Ponce, Arturo. University of Texas at San Antonio; Estados Unidos Fil: Whetten, Robert L.. University of Texas at San Antonio; Estados Unidos Fil: Whetten, Robert L.. University of Texas at San Antonio; Estados Unidos Fil: Mariscal, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Mariscal, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Yacaman, Miguel Jose. University of Texas at San Antonio; Estados Unidos Fil: Yacaman, Miguel Jose. University of Texas at San Antonio; Estados Unidos |
| Databáze: | OpenAIRE |
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