1
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Hu J, Wang X. Infrared Photodissociation Spectroscopy of Dinuclear Vanadium-Group Metal Carbonyl Complexes: Diatomic Synergistic Activation of Carbon Monoxide. Molecules 2024; 29:2831. [PMID: 38930895 PMCID: PMC11206424 DOI: 10.3390/molecules29122831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Revised: 06/10/2024] [Accepted: 06/12/2024] [Indexed: 06/28/2024] Open
Abstract
The geometric structure and bonding features of dinuclear vanadium-group transition metal carbonyl cation complexes in the form of VM(CO)n+ (n = 9-11, M = V, Nb, and Ta) are studied by infrared photodissociation spectroscopy in conjunction with density functional calculations. The homodinuclear V2(CO)9+ is characterized as a quartet structure with CS symmetry, featuring two side-on bridging carbonyls and an end-on semi-bridging carbonyl. In contrast, for the heterodinuclear VNb(CO)9+ and VTa(CO)9+, a C2V sextet isomer with a linear bridging carbonyl is determined to coexist with the lower-lying CS structure analogous to V2(CO)9+. Bonding analyses manifest that the detected VM(CO)9+ complexes featuring an (OC)6M-V(CO)3 pattern can be regarded as the reaction products of two stable metal carbonyl fragments, and indicate the presence of the M-V d-d covalent interaction in the CS structure of VM(CO)9+. In addition, it is demonstrated that the significant activation of the bridging carbonyls in the VM(CO)9+ complexes is due in large part to the diatomic cooperation of M-V, where the strong oxophilicity of vanadium is crucial to facilitate its binding to the oxygen end of the carbonyl groups. The results offer important insight into the structure and bonding of dinuclear vanadium-containing transition metal carbonyl cluster cations and provide inspiration for the design of active vanadium-based diatomic catalysts.
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Affiliation(s)
| | - Xuefeng Wang
- Shanghai Key Laboratory of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China;
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2
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Gan W, Geng L, Huang B, Hansen K, Luo Z. Dehydrogenation of diborane on small Nb n+ clusters. Phys Chem Chem Phys 2024; 26:9586-9592. [PMID: 38465400 DOI: 10.1039/d3cp06135c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
The reactivity of Nbn+ (1 ≤ n ≤ 21) clusters with B2H6 is studied by using a self-developed multiple-ion laminar flow tube reactor combined with a triple quadrupole mass spectrometer (MIFT-TQMS). The Nbn+ clusters were generated by a magnetron sputtering source and reacted with the B2H6 gas under fully thermalized conditions in the downstream flow tube where the reaction time was accurately controlled and adjustable. The complete and partial dehydrogenation products NbnB1-4+ and NbnB1-4H1,2,4+ were detected, indicative of the removal of H2 and likely BHx moieties. Interestingly, these NbnB1-4+ and NbnB1-4H1,2,4+ products are limited to 3 ≤ n ≤ 6, suggesting that the small Nbn+ clusters are relatively more reactive than the larger Nbn>6+ clusters under the same conditions. By varying the B2H6 gas concentrations and the reactant doses introduced into the flow tube, and by changing the reaction time, we performed a detailed analysis of the reaction dynamics in combination with the DFT-calculated thermodynamics. It is demonstrated that the lack of cooperative active sites on the Nb1+ cations accounts for the weakened dehydrogenation efficiency. Nb2+ forms partial dehydrogenation products at a faster rate. In contrast, the Nbn>6+ clusters are subject to more flexible vibrational relaxation which disperse the energy gain of B2H6-adsorption and thus are unable to overcome the energy barriers for subsequent hydrogen atom transfer and H2 release.
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Affiliation(s)
- Wen Gan
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Lijun Geng
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Benben Huang
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Klavs Hansen
- School of Chemical Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhixun Luo
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
- Center for Joint Quantum Studies and Department of Physics, School of Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
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3
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Zhang FX, Zhang YH, Wang M, Ma JB. Nitrogen adsorption on Nb 2C 6H 4+ cations: the important role of benzyne ( ortho-C 6H 4). Phys Chem Chem Phys 2024; 26:3912-3919. [PMID: 38230689 DOI: 10.1039/d3cp05524h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
N2 adsorption is a prerequisite for activation and transformation. Time-of-flight mass spectrometry experiments show that the Nb2C6H4+ cation, resulting from the gas-phase reaction of Nb2+ with C6H6, is more favorable for N2 adsorption than Nb+ and Nb2+ cations. Density functional theory calculations reveal the effect of the ortho-C6H4 ligand on N2 adsorption. In Nb2C6H4+, interactions between the Nb-4d and C-2p orbitals enable the Nb2+ cation to form coordination bonds with the ortho-C6H4 ligand. Although the ortho-C6H4 ligand in Nb2C6H4+ is not directly involved in the reaction, its presence increases the polarity of the cluster and brings the highest occupied molecular orbital (HOMO) closer to the lowest occupied molecular orbital (LUMO) of N2, thereby increasing the N2 adsorption energy, which effectively facilitates N2 adsorption and activation. This study provides fundamental insights into the mechanisms of N2 adsorption in "transition metal-organic ligand" systems.
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Affiliation(s)
- Feng-Xiang Zhang
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
| | - Yi-Heng Zhang
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
| | - Ming Wang
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
| | - Jia-Bi Ma
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
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4
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Wang M, Zhang FX, Chen ZY, Ma JB. Activation and Transformation of Methane on Boron-Doped Cobalt Oxide Cluster Cations CoBO 2. Inorg Chem 2024; 63:1537-1542. [PMID: 38181068 DOI: 10.1021/acs.inorgchem.3c03112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2024]
Abstract
The cleavage of inert C-H bonds in methane at room temperature and the subsequent conversion into value-added products are quite challenging. Herein, the reactivity of boron-doped cobalt oxide cluster cations CoBO2+ toward methane under thermal collision conditions was studied by mass spectrometry experiments and quantum-chemical calculations. In this reaction, one H atom and the CH3 unit of methane were transformed separately to generate the product metaboric acid (HBO2) and one CoCH3+ ion, respectively. Theoretical calculations strongly suggest that a catalytic cycle can be completed by the recovery of CoBO2+ through the reaction of CoCH3+ with sodium perborate (NaBO3), and this reaction generates sodium methoxide (CH3ONa) as the other value-added product. This study shows that boron-doped cobalt oxide species are highly reactive to facilitate thermal methane transformation and may open a way to develop more effective approaches for methane (CH4) activation and conversion under mild conditions.
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Affiliation(s)
- Ming Wang
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, China
| | - Feng-Xiang Zhang
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, China
| | - Zhi-Ying Chen
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, China
| | - Jia-Bi Ma
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, China
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5
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Yang Y, Zhao Y, He S. Conversion of CH
4
Catalyzed by Gas Phase Ions Containing Metals. Chemistry 2022; 28:e202200062. [DOI: 10.1002/chem.202200062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Indexed: 11/09/2022]
Affiliation(s)
- Yuan Yang
- Green Catalysis Center and College of Chemistry Zhengzhou University Zhengzhou 450001 P. R. China
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China
| | - Yan‐Xia Zhao
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China
- Beijing National Laboratory for Molecular Sciences and CAS Research/Education Centre of Excellence in Molecular Sciences Beijing 100190 P. R. China
| | - Sheng‐Gui He
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 P. R. China
- Beijing National Laboratory for Molecular Sciences and CAS Research/Education Centre of Excellence in Molecular Sciences Beijing 100190 P. R. China
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6
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Merriles DM, Nielson C, Tieu E, Morse MD. Chemical Bonding and Electronic Structure of the Early Transition Metal Borides: ScB, TiB, VB, YB, ZrB, NbB, LaB, HfB, TaB, and WB. J Phys Chem A 2021; 125:4420-4434. [PMID: 34003640 DOI: 10.1021/acs.jpca.1c02886] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The predissociation thresholds of the early transition metal boride diatomics (MB, M = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta, W) have been measured using resonant two-photon ionization (R2PI) spectroscopy, allowing for a precise assignment of the bond dissociation energy (BDE). No previous experimental measurements of the BDE exist in the literature for these species. Owing to the high density of electronic states arising from the ground and low-lying separated atom limits in these open d-subshell species, a congested spectrum of vibronic transitions is observed as the energy of the ground separated atom limit is approached. Nonadiabatic and spin-orbit interactions among these states, however, provide a pathway for rapid predissociation as soon as the ground separated atom limit is reached, leading to a sharp decrease in signal to background levels when this limit is reached. Accordingly, the BDEs of the early transition metal borides have been assigned as D0(ScB) 1.72(6) eV, D0(TiB) 1.956(16) eV, D0(VB) 2.150(16) eV, D0(YB) 2.057(3) eV, D0(ZrB) 2.573(5) eV, D0(NbB) 2.989(12) eV, D0(LaB) 2.086(18) eV, D0(HfB) 2.593(3) eV, D0(TaB) 2.700(3) eV, and D0(WB) 2.730(4) eV. Additional insight into the chemical bonding and electronic structures of these species has been achieved by quantum chemical calculations.
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Affiliation(s)
- Dakota M Merriles
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Christopher Nielson
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Erick Tieu
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Michael D Morse
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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7
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Li Y, Wang M, Ding YQ, Zhao CY, Ma JB. Consecutive methane activation mediated by single metal boride cluster anions NbB 4. Phys Chem Chem Phys 2021; 23:12592-12599. [PMID: 34047332 DOI: 10.1039/d1cp01418h] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cleavage of all C-H bonds in two methane molecules by gas-phase cluster ions at room temperature is a challenging task. Herein, mass spectrometry and quantum chemical calculations have been used to identify one single metal boride cluster anions NbB4- that can activate eight C-H bonds in two methane molecules and release one H2 molecule each time under thermal collision conditions. In these consecutive reactions, the loaded Nb atoms and the support B4 units play different roles but act synergistically to activate CH4, which is responsible for the interesting reactivity of NbB4-. Moreover, there are some mechanistic differences in these two reactions, including the mechanisms for the first C-H bond activation steps, dihydrogen desorption sites, and major electron donors. This study shows that non-noble metal boride species are reactive enough to facilitate thermal C-H bond cleavages, and boron-based materials may be one kind of potential support material facilitating surface hydrogen transport.
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Affiliation(s)
- Ying Li
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
| | - Ming Wang
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
| | - Yong-Qi Ding
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
| | - Chong-Yang Zhao
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
| | - Jia-Bi Ma
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
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8
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Abstract
Alkanes and [B12X12]2- (X = Cl, Br) are both stable compounds which are difficult to functionalize. Here we demonstrate the formation of a boron-carbon bond between these substances in a two-step process. Fragmentation of [B12X12]2- in the gas phase generates highly reactive [B12X11]- ions which spontaneously react with alkanes. The reaction mechanism was investigated using tandem mass spectrometry and gas-phase vibrational spectroscopy combined with electronic structure calculations. [B12X11]- reacts by an electrophilic substitution of a proton in an alkane resulting in a B-C bond formation. The product is a dianionic [B12X11CnH2n+1]2- species, to which H+ is electrostatically bound. High-flux ion soft landing was performed to codeposit [B12X11]- and complex organic molecules (phthalates) in thin layers on surfaces. Molecular structure analysis of the product films revealed that C-H functionalization by [B12X11]- occurred in the presence of other more reactive functional groups. This observation demonstrates the utility of highly reactive fragment ions for selective bond formation processes and may pave the way for the use of gas-phase ion chemistry for the generation of complex molecular structures in the condensed phase.
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9
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Tran TH, Tran QT, Tran VT. Mechanism of the reaction of VB5+ cluster with methane from density functional theory calculations. COMPUT THEOR CHEM 2020. [DOI: 10.1016/j.comptc.2020.112701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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10
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Tran VT, Tran QT. Geometric and Electronic Structures of VB 40/+ Clusters and Reactivity of the Cationic Cluster with Methane from Quantum Chemical Calculations. J Phys Chem A 2019; 123:9223-9233. [PMID: 31585037 DOI: 10.1021/acs.jpca.9b08536] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Quantum chemical methods have been employed to study the geometric and electronic structures of VB40/+ clusters and the mechanism of the reaction of the cationic clusters with methane. It was found that the ground states of the neutral and cationic clusters were 4A' and 3A' of a planar isomer in Cs symmetry in which vanadium atom side-on binds to the rhombic B4 moiety. The ionization energy of the neutral cluster was calculated to be 7.13 eV at the CCSD(T) level. The reaction pathways on the triplet and quintet potential energy profiles of the dehydrogenation and elimination of V+ in the reaction of VB4+ cluster with methane were established based on the BPW91 functional calculations. Both of the dehydrogenation and elimination of V+ in the reaction of VB4+ cluster with methane were initiated by the B4 moiety of the VB4+ cluster, and these two reaction channels were thermodynamically and kinetically favorable. The dehydrogenation and elimination of V+ in the reaction of VB4+ cluster with methane were exothermic processes.
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Affiliation(s)
- Van Tan Tran
- Theoretical and Physical Chemistry Division , Dong Thap University , 783-Pham Huu Lau , Cao Lanh City , Dong Thap Vietnam
| | - Quoc Tri Tran
- Theoretical and Physical Chemistry Division , Dong Thap University , 783-Pham Huu Lau , Cao Lanh City , Dong Thap Vietnam
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11
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Pham HT, Pham-Ho MP, Nguyen MT. Impressive capacity of the B7− and V2B7 clusters for CO2 capture. Chem Phys Lett 2019. [DOI: 10.1016/j.cplett.2019.04.087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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12
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Selective Generation of Free Hydrogen Atoms in the Reaction of Methane with Diatomic Gold Boride Cations. ACTA ACUST UNITED AC 2019. [DOI: 10.1515/zpch-2018-1334] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Abstract
The thermal reaction of diatomic gold boride cation AuB+ with methane has been studied by using state-of-the-art mass spectrometry in conjunction with density functional theory calculations. The AuB+ ion can activate a methane molecule to produce exclusively the free hydrogen atom, an important intermediate in hydrocarbon transformation. This result is different from the reactivity of AuC+ and CuB+ counterparts with methane in previous studies. The AuC+ cation mainly transforms methane into ethylene. The CuB+ reaction system principally generates the free hydrogen atoms, but it also gives rise a portion of ethylene-like product H2B−CH2. The B atom of AuB+ is the active site to activate methane. The strong relativistic effect on gold plays an important role for the product selectivity. The mechanistic insights obtained from this study provide guidance for rational design of active sites with high product selectivity toward methane activation.
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13
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Zhou S, Sun X, Yue L, Schlangen M, Schwarz H. Tuning the Reactivities of the Heteronuclear [Al
n
V3−n
O7−n
]+
(n=
1, 2) Cluster Oxides towards Methane by Varying the Composition of the Metal Centers. Chemistry 2019; 25:2967-2971. [DOI: 10.1002/chem.201805908] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Shaodong Zhou
- Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology; College of Chemical and Biological Engineering; Zhejiang University; 310027 Hangzhou P. R. China
- Institut für Chemie; Technische Universität Berlin; Straße des 17. Juni 135 10623 Berlin Germany
| | - Xiaoyan Sun
- Institut für Chemie; Technische Universität Berlin; Straße des 17. Juni 135 10623 Berlin Germany
| | - Lei Yue
- Institut für Chemie; Technische Universität Berlin; Straße des 17. Juni 135 10623 Berlin Germany
| | - Maria Schlangen
- Institut für Chemie; Technische Universität Berlin; Straße des 17. Juni 135 10623 Berlin Germany
| | - Helmut Schwarz
- Institut für Chemie; Technische Universität Berlin; Straße des 17. Juni 135 10623 Berlin Germany
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14
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Sengupta T, Chung JS, Kang SG. Account of chemical bonding and enhanced reactivity of vanadium-doped rhodium clusters toward C–H activation: a DFT investigation. Phys Chem Chem Phys 2019; 21:9935-9948. [DOI: 10.1039/c9cp00444k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The chemical bonding and enhanced reactivity of vanadium-doped rhodium clusters toward C–H activation were investigated using DFT.
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Affiliation(s)
- Turbasu Sengupta
- School of Chemical Engineering
- University of Ulsan
- Ulsan 44610
- South Korea
| | - Jin Suk Chung
- School of Chemical Engineering
- University of Ulsan
- Ulsan 44610
- South Korea
| | - Sung Gu Kang
- School of Chemical Engineering
- University of Ulsan
- Ulsan 44610
- South Korea
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15
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Abstract
The increasing supply of natural gas has created a strong demand for developing efficient catalytic processes to upgrade methane, the most stable alkane molecule, into value-added chemicals. Currently, methane conversion in laboratory and industry is mostly performed under high-temperature conditions. A lot of effort has been devoted to exploring chemical entities that are able to activate the C-H bond of methane at lower temperatures, preferably room temperature. Gas phase atomic clusters with limited numbers of atoms are ideal models of active sites on heterogeneous catalysts. The cluster systems are being actively studied to activate methane under room-temperature conditions. State-of-the-art mass spectrometry, photoelectron imaging spectroscopy, and quantum chemistry calculations have been combined in our laboratory to reveal the molecular-level mechanisms of methane activation by atomic clusters. In this Account, we summarize our recent progress on thermal methane activation by metal oxide clusters doped with noble-metal atoms (Au, Pt, and Rh) as well as by oxygen-free species including carbides and borides of base metals (V, Ta, Mo, and Fe). In contrast to the generations of CH3• free radicals in many of the previously reported cluster reactions with methane, the generations of stable products such as formaldehyde, acetylene, and syngas as well as closed-shell species AuCH3 and B3CH3 have been identified for the cluster reaction systems herein. Besides the well recognized mechanisms of methane activation by the O-• radicals through hydrogen atom abstraction and by metal atoms through oxidative addition, the new mechanisms of synergistic methane activation by Lewis acid-base pairs (such as Auδ+-Oδ- and Bδ+-Bδ-) and by dinuclear metal centers (such as Ta-Ta) have been recently revealed. In the reactions between methane and oxide clusters doped with noble-metal atoms, the oxide cluster "supports" can accept the H atoms and the CH x species delivered through the noble-metal atoms and then transform methane into stable oxygenated compounds. The product selectivity (such as formaldehyde versus syngas) can be controlled by different noble-metal atoms (such as Pt versus Rh). The electronic structures of base metal centers can be engineered through carburization so that the low-spin states can be accessible to reduce the C-H bond of methane. Such active base metal centers in low-spin states resemble related noble-metal atoms in methane activation. The boron clusters (such as B3 in VB3+) can be polarized by the metal cations to form the Lewis acid-base pair Bδ+-Bδ- to cleave the C-H bond of methane very easily. These molecular-level mechanisms may well be operative in related heterogeneous catalysis and can be a fundamental basis to design efficient catalysts for activation and conversion of methane under mild conditions.
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Affiliation(s)
- Yan-Xia Zhao
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- Beijing National
Laboratory for Molecular Sciences, CAS Research/Education Center of
Excellence in Molecular Sciences, Beijing 100190, P. R. China
| | - Zi-Yu Li
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- Beijing National
Laboratory for Molecular Sciences, CAS Research/Education Center of
Excellence in Molecular Sciences, Beijing 100190, P. R. China
| | - Yuan Yang
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- Beijing National
Laboratory for Molecular Sciences, CAS Research/Education Center of
Excellence in Molecular Sciences, Beijing 100190, P. R. China
| | - Sheng-Gui He
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- Beijing National
Laboratory for Molecular Sciences, CAS Research/Education Center of
Excellence in Molecular Sciences, Beijing 100190, P. R. China
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16
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Chen Q, Zhao YX, Jiang LX, Chen JJ, He SG. Coupling of Methane and Carbon Dioxide Mediated by Diatomic Copper Boride Cations. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201808780] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Qiang Chen
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species; Institute of Chemistry; Chinese Academy of Sciences; Beijing 100190 P. R. China
- Beijing National Laboratory for Molecular Sciences; CAS Research/Education Center of Excellence in Molecular Sciences; Beijing 100190 P. R. China
| | - Yan-Xia Zhao
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species; Institute of Chemistry; Chinese Academy of Sciences; Beijing 100190 P. R. China
- Beijing National Laboratory for Molecular Sciences; CAS Research/Education Center of Excellence in Molecular Sciences; Beijing 100190 P. R. China
| | - Li-Xue Jiang
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species; Institute of Chemistry; Chinese Academy of Sciences; Beijing 100190 P. R. China
- Beijing National Laboratory for Molecular Sciences; CAS Research/Education Center of Excellence in Molecular Sciences; Beijing 100190 P. R. China
- University of Chinese Academy of Sciences; Beijing 100049 P. R. China
| | - Jiao-Jiao Chen
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species; Institute of Chemistry; Chinese Academy of Sciences; Beijing 100190 P. R. China
- Beijing National Laboratory for Molecular Sciences; CAS Research/Education Center of Excellence in Molecular Sciences; Beijing 100190 P. R. China
- University of Chinese Academy of Sciences; Beijing 100049 P. R. China
| | - Sheng-Gui He
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species; Institute of Chemistry; Chinese Academy of Sciences; Beijing 100190 P. R. China
- Beijing National Laboratory for Molecular Sciences; CAS Research/Education Center of Excellence in Molecular Sciences; Beijing 100190 P. R. China
- University of Chinese Academy of Sciences; Beijing 100049 P. R. China
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17
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Chen Q, Zhao YX, Jiang LX, Chen JJ, He SG. Coupling of Methane and Carbon Dioxide Mediated by Diatomic Copper Boride Cations. Angew Chem Int Ed Engl 2018; 57:14134-14138. [PMID: 30203446 DOI: 10.1002/anie.201808780] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Indexed: 11/11/2022]
Abstract
The use of CH4 and CO2 to produce value-added chemicals via direct C-C coupling is a challenging chemistry problem because of the inertness of these two molecules. Herein, mass spectrometric experiments and high-level quantum-chemical calculations have identified the first diatomic species (CuB+ ) that can couple CH4 with CO2 under thermal collision conditions to produce ketene (H2 C=C=O), an important intermediate in synthetic chemistry. The order to feed the reactants (CH4 and CO2 ) is important and CH4 should be firstly fed to produce the C2 product. Molecular-level mechanisms including control of product selectivity have been revealed for coupling of CH4 with CO2 under mild conditions.
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Affiliation(s)
- Qiang Chen
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center of Excellence in Molecular Sciences, Beijing, 100190, P. R. China
| | - Yan-Xia Zhao
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center of Excellence in Molecular Sciences, Beijing, 100190, P. R. China
| | - Li-Xue Jiang
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center of Excellence in Molecular Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Jiao-Jiao Chen
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center of Excellence in Molecular Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Sheng-Gui He
- State Key Laboratory for Structural Chemistry of, Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center of Excellence in Molecular Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
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