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Theoretical Study of Zirconium Isomorphous Substitution into Zeolite Frameworks. Molecules 2019; 24:molecules24244466. [PMID: 31817516 PMCID: PMC6943428 DOI: 10.3390/molecules24244466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 11/28/2019] [Accepted: 12/03/2019] [Indexed: 11/30/2022] Open
Abstract
Systematic periodic density functional theory computations including dispersion correction (DFT-D) were carried out to determine the preferred location site of Zr atoms in sodalite (SOD) and CHA-type topology frameworks, including alumino-phosphate-34 (AlPO-34) and silico-alumino-phosphate-34 (SAPO-34), and to determine the relative stability and Brönsted acidity of Zr-substituted forms of SOD, AlPO-34, and SAPO-34. Mono and multiple Zr atom substitutions were considered. The Zr substitution causes obvious structural distortion because of the larger atomic radius of Zr than that of Si, however, Zr-substituted forms of zeolites are found to be more stable than pristine zeolites. Our results demonstrate that in the most stable configurations, the preferred favorable substitutions of Zr in substituted SOD have Zr located at the neighboring sites of the Al-substituted site. However, in the AlPO-34 and SAPO-34 frameworks, the Zr atoms are more easily distributed in a dispersed form, rather than being centralized. Brönsted acidity of substituted zeolites strongly depends on Zr content. For SOD, substitution of Zr atoms reduces Brönsted acidity. However, for Zr-substituted forms of AlPO-34 and SAPO-34, Brönsted acidity of the Zr-O(H)-Al acid sites are, at first, reduced and, then, the presence of Zr atoms substantially increased Brönsted acidity of the Zr-O(H)-Al acid site. The results in the SAPO-34-Zr indicate that more Zr atoms substantially increase Brönsted acidity of the Si-O(H)-Al acid site. It is suggested that substituted heteroatoms play an important role in regulating and controlling structural stability and Brönsted acidity of zeolites.
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Wang J, Chen Z, Yu Y, Tang Z, Shen K, Wang R, Liu H, Huang X, Liu Y. Hollow core-shell structured TS-1@S-1 as an efficient catalyst for alkene epoxidation. RSC Adv 2019; 9:37801-37808. [PMID: 35541812 PMCID: PMC9075760 DOI: 10.1039/c9ra07893b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 11/11/2019] [Indexed: 11/21/2022] Open
Abstract
Hollow core-shell structured TS-1@S-1 zeolite (HCS-TS) was prepared successfully for the first time, which exhibited excellent activity in the epoxidation of alkenes. Combining TEM, UV-vis, UV-Raman, pyridine-IR, solid-state MAS NMR, XPS and so on characterization, the improvement in the catalytic performance of hollow core-shell structured TS-1@S-1 zeolite was credited to the newly formed superior active sites: defective Ti(OSi)3(OH) species in HCS-TS and six-coordinated titanium active species in uncalcined HCS-TS (HCS-TSP). Interestingly, these two different titanium active species in the samples could be constructed through calcination or not in the same synthesis process. A possible formation mechanism was investigated in detail; it indicated that the hollowing treatment of TS-1 in the first step was conducive to the construction of the new superior active sites in the samples, and there was a synergistic effect on the formation of these active sites between TPAOH and TEOS in the second step of the synthesis process. This strategy is feasible to enhance the catalytic performance of TS-1, and is suitable for the synthesis of TS-1 on an industrial scale.
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Affiliation(s)
- J Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University North Zhongshan Rd 3663 Shanghai 200062 P. R. China +86-21-6223-2058 +86-21-6223-2058
| | - Z Chen
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University North Zhongshan Rd 3663 Shanghai 200062 P. R. China +86-21-6223-2058 +86-21-6223-2058
| | - Y Yu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University North Zhongshan Rd 3663 Shanghai 200062 P. R. China +86-21-6223-2058 +86-21-6223-2058
| | - Z Tang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University North Zhongshan Rd 3663 Shanghai 200062 P. R. China +86-21-6223-2058 +86-21-6223-2058
| | - K Shen
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University North Zhongshan Rd 3663 Shanghai 200062 P. R. China +86-21-6223-2058 +86-21-6223-2058
| | - R Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University North Zhongshan Rd 3663 Shanghai 200062 P. R. China +86-21-6223-2058 +86-21-6223-2058
| | - H Liu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University North Zhongshan Rd 3663 Shanghai 200062 P. R. China +86-21-6223-2058 +86-21-6223-2058
| | - X Huang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University North Zhongshan Rd 3663 Shanghai 200062 P. R. China +86-21-6223-2058 +86-21-6223-2058
| | - Y Liu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University North Zhongshan Rd 3663 Shanghai 200062 P. R. China +86-21-6223-2058 +86-21-6223-2058
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Fang X, Wu L, Yu Y, Sun L, Liu Y. Improving the catalytic performance of TS-1 through Zn(AC)2 modification. CATAL COMMUN 2018. [DOI: 10.1016/j.catcom.2018.05.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022] Open
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Yang G, Zhou L. Active Sites of M(IV)-incorporated Zeolites (M = Sn, Ti, Ge, Zr). Sci Rep 2017; 7:16113. [PMID: 29170532 PMCID: PMC5701051 DOI: 10.1038/s41598-017-16409-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 11/13/2017] [Indexed: 12/16/2022] Open
Abstract
M(IV)-incorporated zeolites have recently aroused wide interest due to outstanding catalytic effects while their active sites remain largely elusive. Here periodic density functional theory calculations are conducted finding that active sites are determined jointly by identity of M(IV) ions, topology of zeolites, type of framework species and choice of T sites. All M2(IV) active sites in BEA zeolites are penta-coordinated with chemisorption of one water while subsequent water molecules that form only H-bonds promote chemisorption of the first water, especially the second water possessing comparable or even higher adsorption strengths as the first water; Ti(IV) and Ge(IV) active sites at the intersection remain penta-coordinated and Sn(IV) and Zr(IV) active sites prefer to hexa-coordination although potentially expanded to hepta-coordination. Different from other zeolites, Ti(IV) active sites in FER zeolites are hexa-coordinated as Sn(IV) active sites, due to the promoting effect of the first water. Lewis acidic defects expand Ti(IV) active sites to hexa-coordination while inhibit the formation of hepta-coordinated Sn(IV) species. Two forms of Brϕnsted acidic defects exist for Sn(IV) sites instead of only one for Ti(IV) sites, and all M(IV) Brϕnsted acidic defects, regardless of different acidic forms and M(IV) ions, can chemisorb only one water.
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Affiliation(s)
- Gang Yang
- College of Resources and Environment, Southwest University, Chongqing, 400715, China.
- Schuit Institute of Catalysis, Eindhoven University of Technology, Eindhoven, 5600MB, The Netherlands.
| | - Lijun Zhou
- College of Resources and Environment, Southwest University, Chongqing, 400715, China
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Zheng A, Liu SB, Deng F. 31P NMR Chemical Shifts of Phosphorus Probes as Reliable and Practical Acidity Scales for Solid and Liquid Catalysts. Chem Rev 2017; 117:12475-12531. [DOI: 10.1021/acs.chemrev.7b00289] [Citation(s) in RCA: 196] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anmin Zheng
- State
Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
National Center for Magnetic Resonance in Wuhan, Key Laboratory of
Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, the Chinese Academy of Sciences, Wuhan 430071, China
| | - Shang-Bin Liu
- Institute
of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Feng Deng
- State
Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
National Center for Magnetic Resonance in Wuhan, Key Laboratory of
Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, the Chinese Academy of Sciences, Wuhan 430071, China
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Wu L, Zhao S, Lin L, Fang X, Liu Y, He M. In-depth understanding of acid catalysis of solvolysis of propene oxide over titanosilicates and titanosilicate/H2O2 systems. J Catal 2016. [DOI: 10.1016/j.jcat.2016.01.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Wu L, Deng X, Zhao S, Yin H, Zhuo Z, Fang X, Liu Y, He M. Synthesis of a highly active oxidation catalyst with improved distribution of titanium coordination states. Chem Commun (Camb) 2016; 52:8679-82. [DOI: 10.1039/c6cc03318k] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A facile strategy was carried out to construct a high-performance titanosilicate oxidation catalyst with optimized distribution of titanium coordination states.
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Affiliation(s)
- Lizhi Wu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Xiujuan Deng
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Shufang Zhao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Hanmei Yin
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Zuoxi Zhuo
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | | | - Yueming Liu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Mingyuan He
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
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Zhuang J, Han X, Bao X. In-situ 31P MAS NMR probing of the active centers in Ti silicalite molecular sieve. CATAL COMMUN 2015. [DOI: 10.1016/j.catcom.2015.01.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Zwitterionic versus canonical amino acids over the various defects in zeolites: a two-layer ONIOM calculation. Sci Rep 2014; 4:6594. [PMID: 25307449 PMCID: PMC4194432 DOI: 10.1038/srep06594] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 09/17/2014] [Indexed: 12/01/2022] Open
Abstract
Defects are often considered as the active sites for chemical reactions. Here a variety of defects in zeolites are used to stabilize zwitterionic glycine that is not self-stable in gas phase; in addition, effects of acidic strengths and zeolite channels on zwitterionic stabilization are demonstrated. Glycine zwitterions can be stabilized by all these defects and energetically prefer to canonical structures over Al and Ga Lewis acidic sites rather than Ti Lewis acidic site, silanol and titanol hydroxyls. For titanol (Ti-OH), glycine interacts with framework Ti and hydroxyl sites competitively, and the former with Lewis acidity predominates. The transformations from canonical to zwitterionic glycine are obviously more facile over Al and Ga Lewis acidic sites than over Ti Lewis acidic site, titanol and silanol hydroxyls. Charge transfers that generally increase with adsorption energies are found to largely decide the zwitterionic stabilization effects. Zeolite channels play a significant role during the stabilization process. In absence of zeolite channels, canonical structures predominate for all defects; glycine zwitterions remain stable over Al and Ga Lewis acidic sites and only with synergy of H-bonding interactions can exist over Ti Lewis acidic site, while automatically transform to canonical structures over silanol and titanol hydroxyls.
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Zhuo Z, Wu L, Wang L, Ding Y, Zhang X, Liu Y, He M. Lewis acidic strength controlled highly selective synthesis of oxime via liquid-phase ammoximation over titanosilicates. RSC Adv 2014. [DOI: 10.1039/c4ra08799b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The Lewis acidity of titanosilicates determines oxime selectivity in ammoximation by influencing the reaction activation energy of Ti–OOH for the highly efficient formation of NH2OH.
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Affiliation(s)
- Zuoxi Zhuo
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai, China
| | - Lizhi Wu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai, China
| | - Lei Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai, China
| | - Yichun Ding
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai, China
| | - Xiaoqian Zhang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai, China
| | - Yueming Liu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai, China
| | - Mingyuan He
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai, China
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Zheng A, Liu SB, Deng F. Acidity characterization of heterogeneous catalysts by solid-state NMR spectroscopy using probe molecules. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2013; 55-56:12-27. [PMID: 24094848 DOI: 10.1016/j.ssnmr.2013.09.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 09/02/2013] [Accepted: 09/04/2013] [Indexed: 06/02/2023]
Abstract
Characterization of the surface acidic properties of solid acid catalysts is a key issue in heterogeneous catalysis. Important acid features of solid acids, such as their type (Brønsted vs. Lewis acid), distribution and accessibility (internal vs. external sites), concentration (amount), and strength of acid sites are crucial factors dictating their reactivity and selectivity. This short review provides information on different solid-state NMR techniques used for acidity characterization of solid acid catalysts. In particular, different approaches using probe molecules containing a specific nucleus of interest, such as pyridine-d5, 2-(13)C-acetone, trimethylphosphine, and trimethylphosphine oxide, are compared. Incorporation of valuable information (such as the adsorption structure, deprotonation energy, and NMR parameters) from density functional theory (DFT) calculations can yield explicit correlations between the chemical shift of adsorbed probe molecules and the intrinsic acid strength of solid acids. Methods that combine experimental NMR data with DFT calculations can therefore provide both qualitative and quantitative information on acid sites.
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Affiliation(s)
- Anmin Zheng
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
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Wu X, Yang G, Zhou L, Han X. How significant the charge density of olefins to their epoxidation reactions over M4+-substituted zeolitic catalysts: A DFT investigation. COMPUT THEOR CHEM 2013. [DOI: 10.1016/j.comptc.2013.05.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Progress in development and application of solid-state NMR for solid acid catalysis. CHINESE JOURNAL OF CATALYSIS 2013. [DOI: 10.1016/s1872-2067(12)60528-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Lewis and Brönsted acidic sites in M4+-doped zeolites (M=Ti, Zr, Ge, Sn, Pb) as well as interactions with probe molecules: A DFT study. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.molcata.2012.07.013] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Fang X, Wang Q, Zheng A, Liu Y, Wang Y, Deng X, Wu H, Deng F, He M, Wu P. Fluorine-planted titanosilicate with enhanced catalytic activity in alkene epoxidation with hydrogen peroxide. Catal Sci Technol 2012. [DOI: 10.1039/c2cy20446k] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Zhang W, Xu S, Han X, Bao X. In situsolid-state NMR for heterogeneous catalysis: a joint experimental and theoretical approach. Chem Soc Rev 2012; 41:192-210. [DOI: 10.1039/c1cs15009j] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Yang G, Zhou L, Liu X, Han X, Bao X. Density functional calculations on the distribution, acidity, and catalysis of Ti(IV) and Ti(III) ions in MCM-22 zeolite. Chemistry 2011; 17:1614-21. [PMID: 21268164 DOI: 10.1002/chem.201002241] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Indexed: 11/11/2022]
Abstract
Isolated Ti species in zeolites show unique catalytic activities for a variety of chemical reactions. In this work, density functional calculations were used to explore three current concerns: 1) the distributions of Ti(IV) and Ti(III) ions in the MCM-22 zeolite; 2) the Lewis acidity of the Ti(IV) and Ti(III) sites; and 3) activation of alkane C-H bonds by photocatalysis with Ti-doped zeolites. Neither the Ti(IV) nor Ti(III) ions are randomly distributed in the MCM-22 zeolite. The orders of relative stability are very close for the eight Ti(IV) and Ti(III) sites, and the T3 site is the most probable in both cases. The wavelengths for Ti(IV)-Ti(III) excitations were calculated to lie in the range λ=246.9-290.2 nm. The Ti3(IV) site shows Lewis acidity toward NH(3) in two different modes, and these two modes can coexist with each other. The calculated Ti(IV) coordination numbers, Ti(IV)-O bond elongations, and charge transfers caused by NH(3) adsorption are in good agreement with previous results. Similarly, two different NH(3) adsorption modes exist for the Ti3(III) site; the site that exhibits radical transfer from the lattice O to N atoms is preferred due to the higher adsorption energy. This indicates that the Ti3(III) site does not show Lewis acidity, in contrast to the Ti3(IV) site. At the Ti3(III) site, the energy barrier for activating the methane C-H bond was calculated to be 33.3 kJ mol(-1) and is greatly reduced by replacing the hydrogen atoms with methyl groups. In addition, the reactivity is improved when switching from MCM-22 to TS-1 zeolite. The studies on the various Ti species reveal that lattice O atoms rather than Ti(III) radicals are crucial to the activation of alkane C-H bonds. This work provides new insights into and aids understanding of the catalysis by isolated Ti species in zeolites.
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Affiliation(s)
- Gang Yang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, P. R. China.
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Zheng A, Huang SJ, Liu SB, Deng F. Acid properties of solid acid catalysts characterized by solid-state 31P NMR of adsorbed phosphorous probe molecules. Phys Chem Chem Phys 2011; 13:14889-901. [DOI: 10.1039/c1cp20417c] [Citation(s) in RCA: 181] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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LIU X, YIN D, ZHU H, SHEN G. Probe Reactions Catalyzed by Surface Acid Sites of HTS-1. CHINESE JOURNAL OF CATALYSIS 2010. [DOI: 10.3724/sp.j.1088.2010.90516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Guan J, Li X, Yang G, Zhang W, Liu X, Han X, Bao X. Interactions of phosphorous molecules with the acid sites of H-Beta zeolite: Insights from solid-state NMR techniques and theoretical calculations. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.molcata.2009.06.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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