Journal ArticleDOI
Atom-Resolved Imaging of Dynamic Shape Changes in Supported Copper Nanocrystals
Poul L. Hansen,Jakob Birkedal Wagner,Stig Helveg,Jens R. Rostrup-Nielsen,Bjerne S. Clausen,Henrik Topsøe +5 more
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TLDR
In situ transmission electron microscopy is used to obtain atom-resolved images of copper nanocrystals on different supports, which are catalysts for methanol synthesis and hydrocarbon conversion processes for fuel cells.Abstract:
In situ transmission electron microscopy is used to obtain atom-resolved images of copper nanocrystals on different supports. These are catalysts for methanol synthesis and hydrocarbon conversion processes for fuel cells. The nanocrystals undergo dynamic reversible shape changes in response to changes in the gaseous environment. For zinc oxide-supported samples, the changes are caused both by adsorbate-induced changes in surface energies and by changes in the interfacial energy. For copper nanocrystals supported on silica, the support has negligible influence on the structure. Nanoparticle dynamics must be included in the description of catalytic and other properties of nanomaterials. In situ microscopy offers possibilities for obtaining the relevant atomic-scale insight.read more
Citations
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Atomic-Scale Study of in Situ Metal Nanoparticle Synthesis in a Ni/TiO2 System
TL;DR: Fundamental information is provided on understanding and controlling the important parameters involved in the preparation of a well-designed supported Ni catalyst using the incipient wetness technique.
Journal ArticleDOI
Shape Evolution of Metal Nanoparticles in Binary Gas Environment
Jun Meng,Beien Zhu,Yi Gao +2 more
TL;DR: In this article, a multiscale structure reconstruction model is established to describe the equilibrium structures of metal nanoparticles in a mixed gas environment quantitatively, taking NO and CO reaction as a model system, the structures of the Pd, Pt, and Rh NPs in a large range of temperature and pressure are fully presented.
Journal ArticleDOI
Catalyst Deactivation During One-Step Dimethyl Ether Synthesis from Synthesis Gas
TL;DR: In this article, the deactivation of hybrid catalysts during direct DME synthesis under industrially relevant conditions has been investigated with special focus on the influence of each reaction step on the catalyst function corresponding to the other step.
Journal ArticleDOI
Restructuring of cobalt nanoparticles induced by formation and diffusion of monodisperse metal-sulfur complexes.
TL;DR: Time-resolved scanning tunneling microscopy is used to investigate a massive sulfur-induced transformation of a homogeneous array of approximately 2 nm Co nanoparticles into a new cobalt sulfide phase and the underlying atomistic mass-transport process is revealed and, surprisingly, found to be mediated exclusively by the formation and detachment of monosized Co3S4 complexes at the perimeter of the Co nanoparticle.
Journal ArticleDOI
Design of a new reactor-like high temperature near ambient pressure scanning tunneling microscope for catalysis studies.
TL;DR: A new reactor-like high-temperature near ambient pressure scanning tunneling microscope (HT-NAP-STM) for catalysis studies designed for exploration of structures of catalyst surfaces at atomic scale during catalysis or under reaction conditions.
References
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TL;DR: In this article, a system of chemical reactions has been developed which permits the controlled growth of spherical silica particles of uniform size by means of hydrolysis of alkyl silicates and subsequent condensation of silicic acid in alcoholic solutions.
Journal ArticleDOI
Semiconductor Clusters, Nanocrystals, and Quantum Dots
TL;DR: In this article, the authors focus on the properties of quantum dots and their ability to join the dots into complex assemblies creates many opportunities for scientific discovery, such as the ability of joining the dots to complex assemblies.
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Journal ArticleDOI
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