Journal ArticleDOI
Size matters: why nanomaterials are different
Reads0
Chats0
TLDR
The present tutorial review intends to explain the origin of this special behaviour of nanomaterials, where gold ceases to be noble, and 2-3 nm nanoparticles are excellent catalysts which also exhibit considerable magnetism.Abstract:
Gold is known as a shiny, yellow noble metal that does not tarnish, has a face centred cubic structure, is non-magnetic and melts at 1336 K. However, a small sample of the same gold is quite different, providing it is tiny enough: 10 nm particles absorb green light and thus appear red. The meltingtemperature decreases dramatically as the size goes down. Moreover, gold ceases to be noble, and 2–3 nm nanoparticles are excellent catalysts which also exhibit considerable magnetism. At this size they are still metallic, but smaller ones turn into insulators. Their equilibrium structure changes to icosahedral symmetry, or they are even hollow or planar, depending on size. The present tutorial review intends to explain the origin of this special behaviour of nanomaterials.read more
Citations
More filters
Posted Content
Nanomaterials and nanoparticles: Sources and toxicity
TL;DR: A review of the toxicity of nanoparticles is presented in this paper, with the goal of informing public health concerns related to nanoscience while raising awareness of nanomaterials toxicity among scientists and manufacturers handling them.
Journal ArticleDOI
Nanomaterials and nanoparticles: Sources and toxicity
TL;DR: This review reveals the result of life’s long history of evolution in the presence of nanoparticles, and how the human body has adapted to defend itself against nanoparticulate intruders, while raising awareness of nanomaterials’ toxicity among scientists and manufacturers handling them.
Journal ArticleDOI
Functionalizing nanoparticles with biological molecules: developing chemistries that facilitate nanotechnology.
Kim E. Sapsford,W. Russ Algar,Lorenzo Berti,Kelly Boeneman Gemmill,Brendan J. Casey,Eunkeu Oh,Michael H. Stewart,Igor L. Medintz +7 more
TL;DR: Chemistries that Facilitate Nanotechnology Kim E. Sapsford,† W. Russ Algar, Lorenzo Berti, Kelly Boeneman Gemmill,‡ Brendan J. Casey,† Eunkeu Oh, Michael H. Stewart, and Igor L. Medintz .
Journal ArticleDOI
Bimetallic Nanocrystals: Liquid‐Phase Synthesis and Catalytic Applications
Dingsheng Wang,Yadong Li +1 more
TL;DR: This review highlights the recent progress in the chemical synthesis of bimetallic NCs and the control over morphology, size, composition, and structure of bimodal NCs as well as the exploration of their properties and applications.
Journal ArticleDOI
Catalysis by Supported Single Metal Atoms
TL;DR: In this article, the authors discuss the most recent advances in preparing, characterizing, and catalytically testing SACs with a focus on correlating the structural perspective of the anchored single metal atoms to the observed catalytic performances.
References
More filters
Book
Optical Properties of Metal Clusters
U. Kreibig,Michael Vollmer +1 more
TL;DR: In this paper, the authors present a survey of optical spectra of Elemental Metal Clusters and Chain Aggregates and discuss experimental results and experimental methods for metal clustering experiments.
Journal ArticleDOI
Size- and support-dependency in the catalysis of gold
TL;DR: In this article, the adsorption properties and reactivities of gold are summarized in terms of their size dependency from bulk to fine particles, clusters and atoms, and the catalytic performances of gold markedly depend on dispersion, supports, and preparation methods.
Journal ArticleDOI
Phase separation in confined systems
TL;DR: A review of the current state of knowledge of phase separation and phase equilibria in porous materials can be found in this article, where the focus is on fundamental studies of simple fluids and well-characterized materials.
Journal ArticleDOI
When Gold Is Not Noble: Nanoscale Gold Catalysts
A. Sanchez,Stéphane Abbet,Ueli Heiz,Wolf-Dieter Schneider,Hannu Häkkinen,Robert N. Barnett,Uzi Landman +6 more
TL;DR: In this article, temperature-programmed reaction studies of the catalyzed combustion of CO on size-selected small monodispersed Aun (n ≤ 20) gold clusters supported on magnesia, and first-principle simulations reveal the microscopic origins of the observed unusual catalytic activity, with Au8 being the smallest catalytically active size.
Journal ArticleDOI
Charging Effects on Bonding and Catalyzed Oxidation of CO on Au8 Clusters on MgO
Bokwon Yoon,Hannu Häkkinen,Uzi Landman,Anke S. Wörz,Jean-Marie Antonietti,Stéphane Abbet,Ken Judai,Ueli Heiz +7 more
TL;DR: Infrared measurements of the stretch vibration of CO adsorbed on mass-selected gold octamers soft-landed on MgO(001) with coadsorbed O2 show a red shift on an F-center–rich surface with respect to the perfect surface, agreeing with quantum ab initio calculations that predict this shift should arise via electron back-donation to the CO antibonding orbital.