1
|
Meizyte G, Green AE, Gentleman AS, Schaller S, Schöllkopf W, Fielicke A, Mackenzie SR. Free electron laser infrared action spectroscopy of nitrous oxide binding to platinum clusters, Ptn(N2O)+. Phys Chem Chem Phys 2020; 22:18606-18613. [DOI: 10.1039/d0cp02800b] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Infrared multiple-photon dissociation spectroscopy has been applied to study Ptn(N2O)+ (n = 1–8) clusters which represent entrance-channel complexes on the reactive potential energy surface for nitrous oxide decomposition on platinum.
Collapse
Affiliation(s)
- Gabriele Meizyte
- Department of Chemistry
- University of Oxford, Physical and Theoretical Chemistry Laboratory
- Oxford
- UK
| | - Alice E. Green
- Department of Chemistry
- University of Oxford, Physical and Theoretical Chemistry Laboratory
- Oxford
- UK
| | - Alexander S. Gentleman
- Department of Chemistry
- University of Oxford, Physical and Theoretical Chemistry Laboratory
- Oxford
- UK
| | - Sascha Schaller
- Fritz-Haber-Institut der Max-Planck-Gesellschaft
- 14195 Berlin
- Germany
| | | | - André Fielicke
- Fritz-Haber-Institut der Max-Planck-Gesellschaft
- 14195 Berlin
- Germany
- Institut für Optik und Atomare Physik
- Technische Universität Berlin
| | - Stuart R Mackenzie
- Department of Chemistry
- University of Oxford, Physical and Theoretical Chemistry Laboratory
- Oxford
- UK
| |
Collapse
|
2
|
Hübner O, Himmel HJ. Metal Cluster Models for Heterogeneous Catalysis: A Matrix-Isolation Perspective. Chemistry 2018; 24:8941-8961. [PMID: 29457854 DOI: 10.1002/chem.201706097] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Indexed: 01/25/2023]
Abstract
Metal cluster models are of high relevance for establishing new mechanistic concepts for heterogeneous catalysis. The high reactivity and particular selectivity of metal clusters is caused by the wealth of low-lying electronically excited states that are often thermally populated. Thereby the metal clusters are flexible with regard to their electronic structure and can adjust their states to be appropriate for the reaction with a particular substrate. The matrix isolation technique is ideally suited for studying excited state reactivity. The low matrix temperatures (generally 4-40 K) of the noble gas matrix host guarantee that all clusters are in their electronic ground-state (with only a very few exceptions). Electronically excited states can then be selectively populated and their reactivity probed. Unfortunately, a systematic research in this direction has not been made up to date. The purpose of this review is to provide the grounds for a directed approach to understand cluster reactivity through matrix-isolation studies combined with quantum chemical calculations.
Collapse
Affiliation(s)
- Olaf Hübner
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Hans-Jörg Himmel
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| |
Collapse
|
3
|
Li XN, Zou XP, He SG. Metal-mediated catalysis in the gas phase: A review. CHINESE JOURNAL OF CATALYSIS 2017. [DOI: 10.1016/s1872-2067(17)62782-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
4
|
Yang W, Wang Z, Wang Z, Yang Z, Xia C, Peng R, Wu X, Lu Y. Enhanced catalytic activity toward O₂ reduction on Pt-modified La₁-xSrxCo₁-yFeyO₃-δ cathode: a combination study of first-principles calculation and experiment. ACS APPLIED MATERIALS & INTERFACES 2014; 6:21051-21059. [PMID: 25380101 DOI: 10.1021/am505900g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Using the first-principles calculation and the electronic conductivity relaxation (ECR) experimental technique, we investigated the adsorption and dissociation behaviors of O2 on Pt-modified La0.625Sr0.375Co0.25Fe0.75O3-δ (LSCF) surface. Toward the O2 reduction, the calculation results show that the perfect LSCF (100) surface is catalytically less active than both the defective (100) surface and the perfect (110) surface. O2 molecule can weakly adsorb on the perfect LSCF (100) surface with a small adsorption energy of about -0.30 eV, but the dissociation energy barrier of the O2 molecule is about 1.33-1.43 eV. Doping of Pt cluster on the LSCF (100) surface can remarkably enhance its catalytic activity. The adsorption energies of O2 molecules become -1.16 and -1.89 eV for the interfacial Feint site and the Ptbri bridge site of Pt4-cluster, respectively. Meanwhile, the dissociation energy barriers are reduced to 0.37 and 0.53 eV, respectively. The migration energy barrier of the dissociated oxygen from the interfacial Pt to the LSCF surface is 0.66 eV, and it is 2.58 eV from the top site of the Pt cluster to the interfacial Pt site, suggesting that it is extremely difficult for oxygen to migrate over the Pt cluster. The Bader charge analysis results further indicate that the charges transferring from Pt cluster to LSCF surface promote the adsorption and dissociation of O2 molecules. Experimentally, a dramatic decrease of the surface oxygen exchange relaxation time was observed on Pt-modified LSCF cathode, with a chemical surface exchange coefficient increased from 6.05 × 10(-5) cm/s of the bare LSCF cathode to 4.04 × 10(-4) cm/s of the Pt-modified LSCF cathode, agreeing very well with our theoretical predictions.
Collapse
Affiliation(s)
- Wenqiang Yang
- CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China , Hefei, Anhui 230026, People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
5
|
Harding DJ, Fielicke A. Platinum Group Metal Clusters: From Gas-Phase Structures and Reactivities towards Model Catalysts. Chemistry 2014; 20:3258-67. [DOI: 10.1002/chem.201304586] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
6
|
Yamamoto H, Miyajima K, Yasuike T, Mafuné F. Reactions of Neutral Platinum Clusters with N2O and CO. J Phys Chem A 2013; 117:12175-83. [DOI: 10.1021/jp405707p] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hirotaka Yamamoto
- Department of Basic Science,
Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Ken Miyajima
- Department of Basic Science,
Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Tomokazu Yasuike
- Department of Basic Science,
Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Fumitaka Mafuné
- Department of Basic Science,
Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| |
Collapse
|
7
|
Kerpal C, Harding DJ, Rayner DM, Fielicke A. Small Platinum Cluster Hydrides in the Gas Phase. J Phys Chem A 2013; 117:8230-7. [DOI: 10.1021/jp405120u] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christian Kerpal
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195
Berlin, Germany
| | - Dan J. Harding
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195
Berlin, Germany
| | - David M. Rayner
- National Research Council, 100 Sussex Drive, Ottawa, Ontario, Canada K1A
OR6
| | - André Fielicke
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195
Berlin, Germany
- Institut für Optik
und
Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin, Germany
| |
Collapse
|
8
|
Della Gaspera E, Bersani M, Mattei G, Nguyen TL, Mulvaney P, Martucci A. Cooperative effect of Au and Pt inside TiO2 matrix for optical hydrogen detection at room temperature using surface plasmon spectroscopy. NANOSCALE 2012; 4:5972-5979. [PMID: 22907103 DOI: 10.1039/c2nr31443f] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Metal (Au, Pt, Au@Pt) and metal oxide (TiO(2)) nanoparticles are synthesized with colloidal techniques and subsequently used as nanocrystal inks for thin films deposition. The optical properties of Au colloids are strongly influenced by both Pt and TiO(2) interfaces: while platinum causes a damping and a blue-shift of the Au Surface Plasmon Resonance (SPR) peak as a consequence of the metal-metal interaction, the anatase matrix is responsible for the red shift of the plasmon frequency due to the increased refractive index. By a careful tailoring of the nanoparticles synthesis, high quality, scattering-free films composed of an anatase matrix embedding Au, Pt and Au@Pt colloids are deposited at room temperature and stabilized at 200 °C. Room temperature exposure of these films to hydrogen leads to optical changes. In the case of Au, there is a slow blue shift of the surface plasmon band, resulting in a wavelength dependent optical response. Much faster but smaller optical changes occur for titania films containing Pt. When both metals are present, the optical response of the gold is much faster. This is attributed to spillover of hydrogen atoms from platinum to gold. This synergy enables enhanced optical sensing of hydrogen at room temperature by combining the low temperature dissociation of H(2) on Pt with the intensive surface plasmon response of the gold nanocrystals.
Collapse
Affiliation(s)
- Enrico Della Gaspera
- Dipartimento di Ingegneria Industriale, Università di Padova, Via Marzolo, 9, 35131 Padova, Italy
| | | | | | | | | | | |
Collapse
|
9
|
Zhao YX, Wu XN, Ma JB, He SG, Ding XL. Characterization and reactivity of oxygen-centred radicals over transition metal oxide clusters. Phys Chem Chem Phys 2011; 13:1925-38. [DOI: 10.1039/c0cp01171a] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
10
|
Andersson M, Rosén A. Adsorption and reactions of O2 and D2 on small free palladium clusters in a cluster-molecule scattering experiment. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:334223. [PMID: 21386513 DOI: 10.1088/0953-8984/22/33/334223] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The adsorption of oxygen and hydrogen (deuterium) on small neutral palladium clusters was investigated in a cluster beam experiment. The beam passes through two low-pressure reaction cells, and the clusters, with and without adsorbed molecules, are detected using laser ionization and mass spectrometry. Both H(2) and O(2) adsorb efficiently on the palladium clusters with only moderate variations with cluster size in the investigated range, i.e. between 8 and 28 atoms. The co-adsorption of H(2) and O(2) results in the formation of H(2)O, detected as a decrease in the number of adsorbed oxygen atoms with an increasing number of collisions with H(2) molecules. A comparison is done with an earlier similar study of clusters of Pt. Furthermore a comparison is done with what is known for sticking and reactivity of surfaces.
Collapse
Affiliation(s)
- Mats Andersson
- Department of Applied Mechanics, Chalmers University of Technology, SE-41296 Göteborg, Sweden.
| | | |
Collapse
|
11
|
Ončák M, Cao Y, Höckendorf R, Beyer M, Zahradník R, Schwarz H. Thermal NH Bond Activation on Anionic and Cationic Platinum Clusters: Non-Predetermined Reaction Pathways Indicate Transitions to a Bulk Surface Reactivity. Chemistry 2009; 15:8465-8474. [DOI: 10.1002/chem.200900677] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
12
|
Johnson GE, Mitrić R, Bonačić-Koutecký V, Castleman A. Clusters as model systems for investigating nanoscale oxidation catalysis. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.04.003] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
13
|
Zeinalipour-Yazdi CD, van Santen RA. Kinetic Rates and Linear Free Energy Relationships for Water Dissociation on Transition and Noble Metal Dimers. J Phys Chem A 2009; 113:6971-8. [DOI: 10.1021/jp902139m] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Constantinos D. Zeinalipour-Yazdi
- Department of Chemistry, University of Cyprus, CY 1678, Nicosia, Cyprus, and Schuit Institute of Catalysis, Eindhoven University of Technology, P.O. Box 513, Eindhoven, The Netherlands
| | - Rutger A. van Santen
- Department of Chemistry, University of Cyprus, CY 1678, Nicosia, Cyprus, and Schuit Institute of Catalysis, Eindhoven University of Technology, P.O. Box 513, Eindhoven, The Netherlands
| |
Collapse
|
14
|
Johnson GE, Mitrić R, Nössler M, Tyo EC, Bonačić-Koutecký V, Castleman AW. Influence of Charge State on Catalytic Oxidation Reactions at Metal Oxide Clusters Containing Radical Oxygen Centers. J Am Chem Soc 2009; 131:5460-70. [DOI: 10.1021/ja807499z] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Grant E. Johnson
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Roland Mitrić
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Melanie Nössler
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Eric C. Tyo
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Vlasta Bonačić-Koutecký
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - A. W. Castleman
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| |
Collapse
|
15
|
Johnson GE, Mitrić R, Tyo EC, Bonačić-Koutecký V, Castleman AW. Stoichiometric Zirconium Oxide Cations as Potential Building Blocks for Cluster Assembled Catalysts. J Am Chem Soc 2008; 130:13912-20. [DOI: 10.1021/ja803246n] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Grant E. Johnson
- Departments of Chemistry and Physics, Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Roland Mitrić
- Departments of Chemistry and Physics, Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Eric C. Tyo
- Departments of Chemistry and Physics, Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Vlasta Bonačić-Koutecký
- Departments of Chemistry and Physics, Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - A. W. Castleman
- Departments of Chemistry and Physics, Pennsylvania State University, University Park, Pennsylvania 16802, and Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| |
Collapse
|
16
|
Xie Y, He SG, Dong F, Bernstein ER. Reaction of carbon monoxide and hydrogen on neutral Nb8 clusters in the gas phase. J Chem Phys 2008; 128:044306. [DOI: 10.1063/1.2813348] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
|
17
|
Xu Y, Getman RB, Shelton WA, Schneider WF. A first-principles investigation of the effect of Pt cluster size on CO and NO oxidation intermediates and energetics. Phys Chem Chem Phys 2008; 10:6009-18. [DOI: 10.1039/b805179h] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
|
18
|
Adlhart C, Uggerud E. Mechanisms for the Dehydrogenation of Alkanes on Platinum: Insights Gained from the Reactivity of Gaseous Cluster Cations, Ptn+n=1–21. Chemistry 2007; 13:6883-90. [PMID: 17539036 DOI: 10.1002/chem.200700501] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Rates for the dihydrogen elimination of methane, ethane, and propane with cationic platinum clusters, Pt(n) (+) (1<or=n<or=21), were measured under binary collision conditions in a Fourier transform ion cyclotron resonance mass spectrometer (FTICR). The reaction rate for a given cluster, Ptn +, follows the trend k(CH4)<k (C2H6)<k(C3H8). Methane is particular in the sense that reactivity is highly variable; some clusters (n=1-3, 5-9, 11, 12, 15) are very reactive towards methane, while all other clusters react with low efficiency or not at all. For propane, all clusters react efficiently, while the reactivity of ethane lies in-between that of methane and propane. By necessity, dihydrogen elimination of methane occurs according to a 1,1-elimination mechanism. Ethane dehydrogenation takes place according to both a 1,1- and a 1,2-mechanism. The difference between the 1,1- and 1,2-mechanisms is well displayed in specifically increased rates for those clusters that were inefficient in the reaction with methane, as well as in the observed selectivity for H2, HD, and D2 elimination in the reaction with [D3]-1,1,1-ethane. Some twofold dihydrogen elimination is observed as well. The outcome of reactions with C2H6 in the presence of D(2) demonstrates exchange of all hydrogen atoms in [PtnC2H4]+ with deuterium atoms. A potential energy diagram with a high barrier for the second H2 elimination summarizes these observations. For propane twofold dihydrogen elimination is dominating, and for these reactions a far less regiospecific and more random loss of the hydrogens can be inferred, as was demonstrated by the reactions with [D6]-1,1,1,3,3,3-propane.
Collapse
Affiliation(s)
- Christian Adlhart
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, 0315 Oslo, Norway
| | | |
Collapse
|
19
|
Grönbeck H, Hellman A, Gavrin A. Structural, Energetic, and Vibrational Properties of NOx Adsorption on Agn, n = 1−8. J Phys Chem A 2007; 111:6062-7. [PMID: 17579372 DOI: 10.1021/jp071117d] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The density functional theory is used to explore structural, electronic, and vibrational properties of NO, NO(2), and NO(3) adsorption on small silver clusters, Ag(n), with n =1-8. Generally, NO adsorbs in a top configuration, whereas NO(2) and NO(3) are adsorbed in bridge configuration. NO2 and NO3 introduce pronounced structural relaxations in the clusters. In particular, the transition size from planar to three-dimensional structures is modified. For each cluster size, the adsorption energies follow the trend E(a) (NO) < E(a) (NO(2)) < E(a) (NO(3)). The adsorption energies show a marked odd/even alternation with a stronger bonding to odd clusters. Analysis of the electronic structure reveals an ionic bond mechanism for NO(2) and NO(3). Odd/even effects are also present in vibrational properties of the adsorbed radicals. With respect to the gas phase, the largest shifts are calculated for adsorption on odd clusters. Possible implications of the results for Ag/Al(2)O(3) HC-SCR catalysts are discussed.
Collapse
Affiliation(s)
- Henrik Grönbeck
- Department of Applied Physics and Competence Centre for Catalysis, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
| | | | | |
Collapse
|
20
|
|
21
|
Chapter 2 Chemical reactivity and catalytic properties of size-selected gas-phase metal clusters. ATOMIC CLUSTERS: FROM GAS PHASE TO DEPOSITED 2007. [DOI: 10.1016/s1571-0785(07)12002-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
22
|
Liu X, Dilger H, Eichel RA, Kunstmann J, Roduner E. A Small Paramagnetic Platinum Cluster in an NaY Zeolite: Characterization and Hydrogen Adsorption and Desorption. J Phys Chem B 2006; 110:2013-23. [PMID: 16471777 DOI: 10.1021/jp0561874] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A well-defined cluster containing 12 equivalent platinum atoms was prepared by ion exchange of an NaY zeolite, followed by hydrogen reduction. It was characterized by electron paramagnetic resonance (EPR) spectroscopy, hyperfine sublevel correlation (HYSCORE), and theoretical calculations. Combing the results of the experiments with density functional calculations, the likely structure of this cluster is icosahedral Pt13Hm, possibly with a low positive charge. The adsorbed H/D on the Pt cluster surface can be exchanged reversibly at room temperature. From H/D desorption experiments, an H2 binding energy of 1.36 eV is derived, in reasonable agreement with the calculated value but clearly larger than that for a (111) Pt single-crystal surface, revealing a finite size effect. While the hydrogen-covered cluster should clearly be regarded as a molecule, it is conceivable that the cluster adopts metallic character upon hydrogen desorption. It is likely that up to m=30 H atoms bind to this cluster with 12 surface atoms, which has important implications for the determination of the dispersion of small Pt catalyst particles by hydrogen chemisorption. Calculations as well as experiments give evidence of an interesting magnetic behavior with high-spin states playing a prominent role. There are strong indications that a reservoir of EPR silent but structurally similar clusters exists which can partly be converted to EPR visible species by H/D exchange or by gas adsorption.
Collapse
Affiliation(s)
- X Liu
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | | | | | | | | |
Collapse
|
23
|
Liu H, Sun S, Xing X, Tang Z. Reactions of platinum cluster ions with benzene. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:1899-904. [PMID: 16715471 DOI: 10.1002/rcm.2524] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
In this work, the cation and anion products of the reactions between platinum clusters produced by laser ablation and the benzene molecules seeded in argon have been studied using a high-resolution reflectron time-of-flight mass spectrometer (RTOFMS). The dominant cation products are [C(6n)H(6n - k)](+) and [Pt(m)(C(6)H(6))(n)](+) complexes, while the dominant anion products are dehydrogenated species, [C(6)H(5)PtH](-), [PtC(12)H(k)](-) and [Pt(m)C(6)H(4) . . . (C(6)H(6))(n)](-), etc. Some important intermediate structures ([PtC(6)H(6)](+), [Pt(C(6)H(6))(2)](+), [Pt(2)(C(6)H(6))(3)](+), [C(6)H(5)PtH](-), [Pt(2)C(6)H(4)](-), [Pt(3)C(6)H(4)](-) and [Pt(4)C(6)H(4)](-)) have been analyzed using density functional theory (DFT) calculations. Different reaction mechanisms are proposed for platinum cluster cations and anions with benzene, respectively.
Collapse
Affiliation(s)
- Hongtao Liu
- State Key Laboratory of Molecular Reaction Dynamics, Center of Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People's Republic of China
| | | | | | | |
Collapse
|
24
|
Böhme DK, Schwarz H. Gasphasenkatalyse mit atomaren und Cluster-Metall-Ionen: ultimative “Single-Site”-Katalysatoren. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200461698] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
25
|
Böhme DK, Schwarz H. Gas-Phase Catalysis by Atomic and Cluster Metal Ions: The Ultimate Single-Site Catalysts. Angew Chem Int Ed Engl 2005; 44:2336-54. [PMID: 15779095 DOI: 10.1002/anie.200461698] [Citation(s) in RCA: 654] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Gas-phase experiments with state-of-the-art techniques of mass spectrometry provide detailed insights into numerous elementary processes. The focus of this Review is on elementary reactions of ions that achieve complete catalytic cycles under thermal conditions. The examples chosen cover aspects of catalysis pertinent to areas as diverse as atmospheric chemistry and surface chemistry. We describe how transfer of oxygen atoms, bond activation, and coupling of fragments can be mediated by atomic or cluster metal ions. In some cases truly unexpected analogies of the idealized gas-phase ion catalysis can be drawn with related chemical transformations in solution or the solid state, and so improve our understanding of the intrinsic operation of a practical catalyst at a strictly molecular level.
Collapse
|
26
|
Balaj OP, Balteanu I, Rossteuscher TTJ, Beyer MK, Bondybey VE. Catalytic Oxidation of CO with N2O on Gas-Phase Platinum Clusters. Angew Chem Int Ed Engl 2004; 43:6519-22. [PMID: 15578778 DOI: 10.1002/anie.200461215] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- O Petru Balaj
- Department Chemie, Lehrstuhl 2 für Physikalische Chemie, Technische Universität München, Lichtenbergstrasse 4, Garching, Germany
| | | | | | | | | |
Collapse
|
27
|
Balaj OP, Balteanu I, Roßteuscher TTJ, Beyer MK, Bondybey VE. Catalytic Oxidation of CO with N2O on Gas-Phase Platinum Clusters. Angew Chem Int Ed Engl 2004. [DOI: 10.1002/ange.200461215] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
28
|
Justes DR, Moore NA, Castleman AW. Reactions of Vanadium and Niobium Oxides with Methanol. J Phys Chem B 2004. [DOI: 10.1021/jp031152u] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- D. R. Justes
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - N. A. Moore
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - A. W. Castleman
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, Pennsylvania 16802
| |
Collapse
|
29
|
Balteanu I, Petru Balaj O, Beyer MK, Bondybey VE. Reactions of platinum clusters195Ptn±, n = 1–24, with N2O studied with isotopically enriched platinum. Phys Chem Chem Phys 2004. [DOI: 10.1039/b405211k] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|