Gold Catalysts

A special issue of Catalysts (ISSN 2073-4344). This special issue belongs to the section "Environmental Catalysis".

Deadline for manuscript submissions: closed (30 September 2011) | Viewed by 148031

Special Issue Editor

Institute of Nanostructured Materials, Palermo Research Division, CNR - ISMN, Via Ugo La Malfa 153, 90146 Palermo, Italy
Interests: synthesis; characterization and structure-activity relationship of supported noble metal (Pt, Pd, Au) for oxidation reactions; metal-support interaction in gold catalysts for low-temperature CO and VOCs oxidation; use of gold for hydrogen purification by selective oxidation of carbon monoxide (PROX); development of Pd and Au catalysts for abatement at low temperature of VOCs and methane emitted by mobile sources; synthesis and characterization of bimetallic Ni-Au catalysts for hydrocarbon steam reforming reaction and syngas production; optimization of Co-based catalysts composition and preparation method for Fischer-Tropsch synthesis
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Special Issue Information

Dear Colleagues,

The interest in using gold as a catalyst component has increased during the last 20 years since the surprisingly high activity in CO oxidation at low temperature was reported for small (3-5 nm) gold particles supported on various oxides. Nowadays, the catalytic applications of gold are explored in several processes, such as CO oxidation, PROX reaction, WGS reaction, NOx and VOCs abatement, hydrotreatment, chemical processing. However, the attainment of the best performing supported gold catalyst is still a challenge. The main reason for this is ascribed to the multiplicity of factors influencing the catalytic activity. The catalytic performances of gold nanoparticles have been correlated in turn with electronic (quantum size effect, oxidation state), structural and support effects (defects, perimeter interface, reducible oxide), but a general consensus has not been reached.  Most of the properties which make active a catalyst strongly depend on the preparation method and pretreatment conditions, therefore, it is difficult to generalize on the basis of catalysts differently prepared and operating under different conditions. Moreover, up to now key questions concerning the reaction mechanisms and the nature of active sites are still matter of debate.

In this special issue we aim at covering recent progress and novel trends in the fields of gold catalysts ranging from the basic research and characterization (TEM, XPS, EXAFS, XRD, FT-IR) studies to the development of new gold catalyst formulations of environmental importance and industrial applications.

Dr. Leonarda F. Liotta
Guest Editor

Keywords

  • Au preparation method
  • Au oxidation state
  • Au-support interface
  • Structural and electronic characterization
  • FT-IR of probe molecules
  • CO oxidation
  • PROX reaction
  • NOx abatement
  • WGS reaction
  • VOC oxidation

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Published Papers (16 papers)

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Editorial

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76 KiB  
Editorial
New Frontiers in Gold Catalyzed Reactions
by Leonarda F. Liotta
Catalysts 2012, 2(2), 299-302; https://doi.org/10.3390/catal2020299 - 29 May 2012
Cited by 4 | Viewed by 6228
Abstract
For many years, gold has been regarded as a poor catalyst due to its chemical inertness towards reactive molecules such as oxygen and hydrogen. The interest in using gold in catalysis has increased during the last 20 years, since Haruta reported the surprisingly [...] Read more.
For many years, gold has been regarded as a poor catalyst due to its chemical inertness towards reactive molecules such as oxygen and hydrogen. The interest in using gold in catalysis has increased during the last 20 years, since Haruta reported the surprisingly high activity in CO oxidation at low temperature for small (3–5 nm) gold particles supported on various oxides. [...] Full article
(This article belongs to the Special Issue Gold Catalysts)

Research

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494 KiB  
Article
Influence of Gold on Ce-Zr-Co Fluorite-Type Mixed Oxide Catalysts for Ethanol Steam Reforming
by Julio Cesar Vargas, Svetlana Ivanova, Sébastien Thomas, Anne-Cécile Roger and Véronique Pitchon
Catalysts 2012, 2(1), 121-138; https://doi.org/10.3390/catal2010121 - 03 Feb 2012
Cited by 12 | Viewed by 8546
Abstract
The effect of gold presence on carbon monoxide oxidation and ethanol steam reforming catalytic behavior of two Ce-Zr-Co mixed oxides catalysts with a constant Co charge and different Ce/Zr ratios was investigated. The Ce-Zr-Co mixed oxides were obtained by the pseudo sol-gel like [...] Read more.
The effect of gold presence on carbon monoxide oxidation and ethanol steam reforming catalytic behavior of two Ce-Zr-Co mixed oxides catalysts with a constant Co charge and different Ce/Zr ratios was investigated. The Ce-Zr-Co mixed oxides were obtained by the pseudo sol-gel like method, based on metallic propionates polymerization and thermal decomposition, whereas the gold-supported Ce-Zr-Co mixed oxides catalysts were prepared using the direct anionic exchange. The catalysts were characterized using XRD, TPR, and EDXS-TEM. The presence of Au in doped Ce-Zr-Co oxide catalyst decreases the temperature necessary to reduce the cobalt and the cerium loaded in the catalyst and favors a different reaction pathway, improving the acetaldehyde route by ethanol dehydrogenation, instead of the ethylene route by ethanol dehydration or methane re-adsorption, thus increasing the catalytic activity and selectivity into hydrogen. Full article
(This article belongs to the Special Issue Gold Catalysts)
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1072 KiB  
Article
The Influence of Base Metal (M) Oxidation State in Au-M-O/TiO2 Systems on Their Catalytic Activity in Carbon Monoxide Oxidation
by Jan Mizera, Nika Spiridis, Robert P. Socha, Małgorzata Zimowska, Ryszard Grabowski, Katarzyna Samson and Józef Korecki
Catalysts 2012, 2(1), 38-55; https://doi.org/10.3390/catal2010038 - 22 Dec 2011
Cited by 8 | Viewed by 8014
Abstract
Base metal promoted gold/titania catalysts were synthesized, characterized and tested in CO oxidation reaction. Catalysts containing dopant metals in higher oxidation states exhibited higher activity than catalysts containing dopants in reduced states. The activity of fresh catalysts promoted by Cu, Fe and Ni [...] Read more.
Base metal promoted gold/titania catalysts were synthesized, characterized and tested in CO oxidation reaction. Catalysts containing dopant metals in higher oxidation states exhibited higher activity than catalysts containing dopants in reduced states. The activity of fresh catalysts promoted by Cu, Fe and Ni was similar to the unpromoted one, but treatment in reducing and oxidizing atmospheres revealed the supremacy of the copper promoted catalyst. The sequential deposition method proved to be better than the co-deposition—precipitation method. An attempt to explain these differences using XPS, FTIR and H2 TPR was performed. Full article
(This article belongs to the Special Issue Gold Catalysts)
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1617 KiB  
Article
Gold/Iron Carbonyl Clusters for Tailored Au/FeOx Supported Catalysts
by Rosa Bonelli, Stefano Zacchini and Stefania Albonetti
Catalysts 2012, 2(1), 1-23; https://doi.org/10.3390/catal2010001 - 21 Dec 2011
Cited by 17 | Viewed by 7185
Abstract
A novel preparation method was developed for the preparation of gold/iron oxide supported catalysts using the bimetallic carbonyl cluster salts [NEt4]4[Au4Fe4(CO)16] and [NEt4][AuFe4(CO)16] as precursors of highly [...] Read more.
A novel preparation method was developed for the preparation of gold/iron oxide supported catalysts using the bimetallic carbonyl cluster salts [NEt4]4[Au4Fe4(CO)16] and [NEt4][AuFe4(CO)16] as precursors of highly dispersed nanoparticles over different supports. A series of catalysts with different metal loadings were prepared and tested in the complete oxidation of dichlorobenzene, toluene, methanol and in the preferential oxidation of CO in the presence of H2 (PROX) as model reactions. The characterization by BET, XRD, TEM, H2-TPR, ICP-AES and XPS point out the way the nature of the precursors and the thermal treatment conditions affected the dispersion of the active phase and their catalytic activity in the studied reactions. Full article
(This article belongs to the Special Issue Gold Catalysts)
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907 KiB  
Article
Pre-Reduction of Au/Iron Oxide Catalyst for Low-Temperature Water-Gas Shift Reaction Below 150 °C
by Shinji Kudo, Taisuke Maki, Takashi Fukuda and Kazuhiro Mae
Catalysts 2011, 1(1), 175-190; https://doi.org/10.3390/catal1010175 - 09 Dec 2011
Cited by 9 | Viewed by 8752
Abstract
Low-temperature water-gas shift reaction (WGS) using gold catalyst is expected to be an attractive technique to realize an efficient on-site hydrogen production process. In this paper, Au/Fe3O4 catalysts for promoting the WGS below 150 °C were developed by a preliminary [...] Read more.
Low-temperature water-gas shift reaction (WGS) using gold catalyst is expected to be an attractive technique to realize an efficient on-site hydrogen production process. In this paper, Au/Fe3O4 catalysts for promoting the WGS below 150 °C were developed by a preliminary reduction of Au/iron oxide (Fe3+) catalyst utilizing high reactivity of Au nano-particles. The reduction was conducted under a CO, H2, or CO/H2O stream at either 140 or 200 °C, and the effect of reduction conditions on the characteristics of the Au/Fe3O4 catalyst and on the catalytic activity in WGS at 80 °C was investigated. The reaction progress during the pre-reduction treatment was qualitatively analyzed, and it was found that the iron oxide in Au/Fe2O3 calcined at 200 °C was easily reduced to Fe3O4 phase in all reduction conditions. The reduction conditions affected the characteristics of both Au and iron oxide, but all of the reduced catalysts had small Fe3O4 particles of less than 20 nm with Au particles on the surface. The surface area and content of cationic Au were high in the order of CO, H2, CO/H2O, and 140, 200 °C. In the WGS test at 80 °C using the developed catalysts, the activities of the catalysts pre-reduced by CO at 140 or 200 °C and by H2 at 140 °C were very high with 100% CO conversion even at such a low temperature. These results indicated that factors such as higher surface area, crystallized Fe3O4, and cationic Au content contributed to the catalytic activity. Full article
(This article belongs to the Special Issue Gold Catalysts)
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6721 KiB  
Article
Nano-Scale Au Supported on Carbon Materials for the Low Temperature Water Gas Shift (WGS) Reaction
by Sonia Gil, Amaya Romero, Antonio de Lucas, Paula Sánchez, Fernando Dorado, Ana Raquel de la Osa, Jesús Manuel García-Vargas and Jose Luis Valverde
Catalysts 2011, 1(1), 155-174; https://doi.org/10.3390/catal1010155 - 09 Dec 2011
Cited by 7 | Viewed by 8063
Abstract
Au-based catalysts supported on carbon materials with different structures such as graphite (G) and fishbone type carbon nanofibers (CNF-F) were prepared using two different methods (impregnation and gold-sol) to be tested in the water gas shift (WGS) reaction. Atomic absorption spectrometry, transmission electron [...] Read more.
Au-based catalysts supported on carbon materials with different structures such as graphite (G) and fishbone type carbon nanofibers (CNF-F) were prepared using two different methods (impregnation and gold-sol) to be tested in the water gas shift (WGS) reaction. Atomic absorption spectrometry, transmission electron microscopy (TEM), temperature-programmed oxidation (TPO), X-ray diffraction (XRD), Raman spectroscopy, elemental analyses (CNH), N2 adsorption-desorption analysis, temperature-programmed reduction (TPR) and temperature-programmed decomposition were employed to characterize both the supports and catalysts. Both the crystalline nature of the carbon supports and the method of gold incorporation had a strong influence on the way in which Au particles were deposited on the carbon surface. The higher crystallinity and the smaller and well dispersed Au particle size were, the higher activity of the catalysts in the WGS reaction was noted. Finally, catalytic activity showed an important dependence on the reaction temperature and steam-to-CO molar ratio. Full article
(This article belongs to the Special Issue Gold Catalysts)
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1124 KiB  
Article
Synthesis and Catalytic Features of Hybrid Metal Nanoparticles Supported on Cellulose Nanofibers
by Akihiro Azetsu, Hirotaka Koga, Akira Isogai and Takuya Kitaoka
Catalysts 2011, 1(1), 83-96; https://doi.org/10.3390/catal1010083 - 25 Nov 2011
Cited by 78 | Viewed by 13084
Abstract
The structural and functional design of metal nanoparticles has recently allowed remarkable progress in the development of high-performance catalysts. Gold nanoparticles (AuNPs) are among the most innovative catalysts, despite bulk Au metal being regarded as stable and inactive. The hybridization of metal NPs [...] Read more.
The structural and functional design of metal nanoparticles has recently allowed remarkable progress in the development of high-performance catalysts. Gold nanoparticles (AuNPs) are among the most innovative catalysts, despite bulk Au metal being regarded as stable and inactive. The hybridization of metal NPs has attracted major interest in the field of advanced nanocatalysts, due to electro-mediated ligand effects. In practical terms, metal NPs need to be supported on a suitable matrix to avoid any undesirable aggregation; many researchers have reported the potential of polymer-supported AuNPs. However, the use of conventional polymer matrices make it difficult to take full advantage of the inherent properties of the metal NPs, since most of active NPs are imbedded inside the polymer support. This results in poor accessibility for the reactants. Herein, we report the topochemical synthesis of Au and palladium (Pd) bimetallic NPs over the surfaces of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibers (TOCNs), and their exceptional catalytic performance. Highly-dispersed AuPdNPs were successfully synthesized in situ on the crystal surfaces of TOCNs with a very high density of carboxylate groups. The AuPdNPs@TOCN nanocomposites exhibit excellent catalytic efficiencies in the aqueous reduction of 4-nitrophenol to 4-aminophenol, depending on the molar ratios of Au and Pd. Full article
(This article belongs to the Special Issue Gold Catalysts)
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1236 KiB  
Article
In Situ Synthesis of Bimetallic Hybrid Nanocatalysts on a Paper-Structured Matrix for Catalytic Applications
by Hirotaka Koga, Yuuka Umemura and Takuya Kitaoka
Catalysts 2011, 1(1), 69-82; https://doi.org/10.3390/catal1010069 - 25 Nov 2011
Cited by 16 | Viewed by 8138
Abstract
Bimetallic nanoparticles have attracted significant attention as their electrochemical and catalytic properties being superior to those of the individual component nanoparticles. In this study, gold-silver hybrid nanoparticles (AuAgNPs) with an Aucore-Agshell nanostructure were successfully synthesized on zinc oxide (ZnO) whiskers. [...] Read more.
Bimetallic nanoparticles have attracted significant attention as their electrochemical and catalytic properties being superior to those of the individual component nanoparticles. In this study, gold-silver hybrid nanoparticles (AuAgNPs) with an Aucore-Agshell nanostructure were successfully synthesized on zinc oxide (ZnO) whiskers. The as-prepared nanocatalyst, denoted AuAgNPs@ZnO whisker, exhibits an excellent catalytic efficiency in the aqueous reduction of 4-nitrophenol to 4-aminophenol; the turnover frequency was up to 40 times higher than that of each component nanoparticle. Their unique features were attributed to the electronic ligand effect at the bimetallic interface. In addition, the AuAgNPs were synthesized on a ZnO whisker-containing paper with a fiber-network microstructure, which was prepared via a papermaking technique. The paper-structured AuAgNPs composite possessed both a paper-like practical utility and a good catalytic performance. Furthermore, the on-paper synthesis process for these bimetallic nanocatalysts is facile. These easy-to-handle nanocatalyst hybrid composites are expected to find a wide range of applications in various chemical and catalytic processes. Full article
(This article belongs to the Special Issue Gold Catalysts)
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755 KiB  
Article
Gold Functionalized Supported Ionic Liquids Catalyst for CO Oxidation
by Svetlana Ivanova, Luis Francisco Bobadilla, Anna Penkova, Francisca Romero Sarria, Miguel Angel Centeno and Jose Antonio Odriozola
Catalysts 2011, 1(1), 52-68; https://doi.org/10.3390/catal1010052 - 25 Nov 2011
Cited by 5 | Viewed by 7983
Abstract
The present study tries to give an insight to the combination of the homogeneous and heterogeneous catalytic properties in a new class of materials. Well dispersed gold nanoparticles on an ionic liquid layer supported on a mineral carrier have been prepared. This work [...] Read more.
The present study tries to give an insight to the combination of the homogeneous and heterogeneous catalytic properties in a new class of materials. Well dispersed gold nanoparticles on an ionic liquid layer supported on a mineral carrier have been prepared. This work is concentrated on the characterizations and understanding of the interactions between all the components of the catalytic system. The application of the materials in the reaction of oxidation of carbon monoxide shows rather unexpected results—a good catalytic activity completely independent of the temperature. Full article
(This article belongs to the Special Issue Gold Catalysts)
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4231 KiB  
Article
Role of the Support Effects on the Catalytic Activity of Gold Clusters: A Density Functional Theory Study
by Min Gao, Andrey Lyalin and Tetsuya Taketsugu
Catalysts 2011, 1(1), 18-39; https://doi.org/10.3390/catal1010018 - 17 Nov 2011
Cited by 38 | Viewed by 11098
Abstract
It is demonstrated that the support effects play a crucial role in the gold nanocatalysis. Two types of support are considered—the “inert” support of hexagonal boron nitride (h-BN) with the N and B vacancy defects and the “active” support of rutile TiO2 [...] Read more.
It is demonstrated that the support effects play a crucial role in the gold nanocatalysis. Two types of support are considered—the “inert” support of hexagonal boron nitride (h-BN) with the N and B vacancy defects and the “active” support of rutile TiO2(110). It is demonstrated that Au and Au2 can be trapped effectively by the vacancy defects in h-BN. In that case, the strong adsorption on the surface defects is accompanied by the charge transfer to/from the adsorbate. The excess of the positive or negative charge on the supported gold clusters can considerably promote their catalytic activity. Therefore gold clusters supported on the defected h-BN surface can not be considered as pseudo-free clusters. We also demonstrate that the rutile TiO2(110) support energetically promotes H2 dissociation on gold clusters. We show that the formation of the OH group near the supported gold cluster is an important condition for H2 dissociation. We demonstrate that the active sites towards H2 dissociation on the supported Aun are located at corners and edges of the gold cluster in the vicinity of the low coordinated oxygen atoms on TiO2(110). Thus catalytic activity of a gold nanoparticle supported on the rutile TiO2(110) surface is proportional to the length of the perimeter interface between the nanoparticle and the support. Full article
(This article belongs to the Special Issue Gold Catalysts)
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Review

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16832 KiB  
Review
Dynamic Processes on Gold-Based Catalysts Followed by Environmental Microscopies
by Eric Genty, Luc Jacobs, Thierry Visart de Bocarmé and Cédric Barroo
Catalysts 2017, 7(5), 134; https://doi.org/10.3390/catal7050134 - 01 May 2017
Cited by 12 | Viewed by 6659
Abstract
Since the early discovery of the catalytic activity of gold at low temperature, there has been a growing interest in Au and Au-based catalysis for a new class of applications. The complexity of the catalysts currently used ranges from single crystal to 3D [...] Read more.
Since the early discovery of the catalytic activity of gold at low temperature, there has been a growing interest in Au and Au-based catalysis for a new class of applications. The complexity of the catalysts currently used ranges from single crystal to 3D structured materials. To improve the efficiency of such catalysts, a better understanding of the catalytic process is required, from both the kinetic and material viewpoints. The understanding of such processes can be achieved using environmental imaging techniques allowing the observation of catalytic processes under reaction conditions, so as to study the systems in conditions as close as possible to industrial conditions. This review focuses on the description of catalytic processes occurring on Au-based catalysts with selected in situ imaging techniques, i.e., PEEM/LEEM, FIM/FEM and E-TEM, allowing a wide range of pressure and material complexity to be covered. These techniques, among others, are applied to unravel the presence of spatiotemporal behaviours, study mass transport and phase separation, determine activation energies of elementary steps, observe the morphological changes of supported nanoparticles, and finally correlate the surface composition with the catalytic reactivity. Full article
(This article belongs to the Special Issue Gold Catalysts)
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970 KiB  
Review
Monometallic Supported Gold Catalysts in Organic Transformations: Ring Making and Ring Breaking
by Krisztián Csankó, Pál Sipos and István Pálinkó
Catalysts 2012, 2(1), 101-120; https://doi.org/10.3390/catal2010101 - 01 Feb 2012
Cited by 3 | Viewed by 8340
Abstract
Supported gold catalysts are highly active in oxidation reactions. Beside the most frequently studied CO oxidation, they are readily applied in the epoxidation of more or less complex olefinic compounds using air or oxygen directly or other oxidants like peroxides of various kinds. [...] Read more.
Supported gold catalysts are highly active in oxidation reactions. Beside the most frequently studied CO oxidation, they are readily applied in the epoxidation of more or less complex olefinic compounds using air or oxygen directly or other oxidants like peroxides of various kinds. Less frequently though, the reverse reaction, ring opening with single or double C–O scission is also investigated. These and other ring making and breaking reactions are reviewed, and the catalytic roles of gold species are described. Full article
(This article belongs to the Special Issue Gold Catalysts)
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1600 KiB  
Review
The Art of Manufacturing Gold Catalysts
by Laura Prati and Alberto Villa
Catalysts 2012, 2(1), 24-37; https://doi.org/10.3390/catal2010024 - 21 Dec 2011
Cited by 51 | Viewed by 9040
Abstract
Gold has been considered as an active catalyst only when suitable techniques of preparation provided high metal dispersion. A comprehensive survey of the different methods now available for preparing active gold catalysts is reported with particular attention to the role of the supporting [...] Read more.
Gold has been considered as an active catalyst only when suitable techniques of preparation provided high metal dispersion. A comprehensive survey of the different methods now available for preparing active gold catalysts is reported with particular attention to the role of the supporting material in determining catalyst characteristics. Full article
(This article belongs to the Special Issue Gold Catalysts)
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1316 KiB  
Review
Synthesis of Gold Catalysts Supported on Mesoporous Silica Materials: Recent Developments
by Luis-Felipe Gutiérrez, Safia Hamoudi and Khaled Belkacemi
Catalysts 2011, 1(1), 97-154; https://doi.org/10.3390/catal1010097 - 02 Dec 2011
Cited by 93 | Viewed by 17187
Abstract
Mesoporous silica materials (MSM) with ordered and controllable porous structure, high surface area, pore volume and thermal stability are very suitable catalyst supports, because they provide high dispersion of metal nanoparticles and facilitate the access of the substrates to the active sites. Since [...] Read more.
Mesoporous silica materials (MSM) with ordered and controllable porous structure, high surface area, pore volume and thermal stability are very suitable catalyst supports, because they provide high dispersion of metal nanoparticles and facilitate the access of the substrates to the active sites. Since the conventional wet-impregnation and deposition-precipitation methods are not appropriate for the incorporation of gold nanoparticles (AuNPs) into MSM, considerable efforts have been made to develop suitable methods to synthesize Au/MSM catalysts, because the incorporation of AuNPs into the channel system can prevent their agglomeration and leaching. In this review, we summarize the main methods to synthesize active gold catalysts supported on MSM. Examples and details of the preparative methods, as well as selected applications are provided. We expect this article to be interesting to researchers due to the wide variety of chemical reactions that can be catalyzed by gold supported catalysts. Full article
(This article belongs to the Special Issue Gold Catalysts)
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443 KiB  
Review
Catalytic Reactions on Model Gold Surfaces: Effect of Surface Steps and of Surface Doping
by José L. C. Fajín, Maria Natália D. S. Cordeiro and José R. B. Gomes
Catalysts 2011, 1(1), 40-51; https://doi.org/10.3390/catal1010040 - 21 Nov 2011
Cited by 8 | Viewed by 7407
Abstract
The adsorption energies and the activation energy barriers for a series of reactions catalyzed by gold surfaces and obtained theoretically through density functional theory (DFT) based calculations were considered to clarify the role of the low coordinated gold atoms and the role of [...] Read more.
The adsorption energies and the activation energy barriers for a series of reactions catalyzed by gold surfaces and obtained theoretically through density functional theory (DFT) based calculations were considered to clarify the role of the low coordinated gold atoms and the role of doping in the catalytic activity of gold. The effect of the surface steps was introduced by comparison of the activation energy barriers and of the adsorption energies on flat gold surfaces such as the Au(111) surface with those on stepped surfaces such as the Au(321) or the Au(110) surfaces. It is concluded that the presence of low coordinated atoms on the latter surfaces increases the adsorption energies of the reactants and decreases the activation energy barriers. Furthermore, the increasing of the adsorption energy of the reaction products can lead to lower overall reaction rates in the presence of low gold coordinated atoms due to desorption limitations. On the other hand, the effect of doping gold surfaces with other transition metal atoms was analyzed using the dissociation reaction of molecular oxygen as a test case. The calculations showed that increasing the silver content in some gold surfaces was related to a considerable increment of the reactivity of bimetallic systems toward the oxygen dissociation. Importantly, that increment in the reactivity was enhanced by the presence of low coordinated atoms in the catalytic surface models considered. Full article
(This article belongs to the Special Issue Gold Catalysts)
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1206 KiB  
Review
Atomically Monodisperse Gold Nanoclusters Catalysts with Precise Core-Shell Structure
by Yan Zhu, Rongchao Jin and Yuhan Sun
Catalysts 2011, 1(1), 3-17; https://doi.org/10.3390/catal1010003 - 07 Sep 2011
Cited by 37 | Viewed by 11019
Abstract
The emphasis of this review is atomically monodisperse Aun nanoclusters catalysts (n = number of metal atom in cluster) that are ideally composed of an exact number of metal atoms. Aun which range in size from a dozen to a [...] Read more.
The emphasis of this review is atomically monodisperse Aun nanoclusters catalysts (n = number of metal atom in cluster) that are ideally composed of an exact number of metal atoms. Aun which range in size from a dozen to a few hundred atoms are particularly promising for nanocatalysis due to their unique core-shell structure and non-metallic electronic properties. Aun nanoclusters catalysts have been demonstrated to exhibit excellent catalytic activity in hydrogenation and oxidation processes. Such unique properties of Aun significantly promote molecule activation by enhancing adsorption energy of reactant molecules on catalyst surface. The structural determination of Aun nanoclusters allows for a precise correlation of particle structure with catalytic properties and also permits the identification of catalytically active sites on the gold particle at an atomic level. By learning these fundamental principles, one would ultimately be able to design new types of highly active and highly selective gold nanocluster catalysts for a variety of catalytic processes. Full article
(This article belongs to the Special Issue Gold Catalysts)
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