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Ebrahim AM, Plonka AM, Rui N, Hwang S, Gordon WO, Balboa A, Senanayake SD, Frenkel AI. Capture and Decomposition of the Nerve Agent Simulant, DMCP, Using the Zeolitic Imidazolate Framework (ZIF-8). ACS APPLIED MATERIALS & INTERFACES 2020; 12:58326-58338. [PMID: 33327718 DOI: 10.1021/acsami.0c12985] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Understanding mechanisms of decontamination of chemical warfare agents (CWA) is an area of intense research aimed at developing new filtration materials to protect soldiers and civilians in case of state-sponsored or terrorist attack. In this study, we employed complementary structural, chemical, and dynamic probes and in situ data collection, to elucidate the complex chemistry, capture, and decomposition of the CWA simulant, dimethyl chlorophosphonate (DMCP). Our work reveals key details of the reactive adsorption of DMCP and demonstrates the versatility of zeolitic imidazolate framework (ZIF-8) as a plausible material for CWA capture and decomposition. The in situ synchrotron-based powder X-ray diffraction (PXRD) and pair distribution function (PDF) studies, combined with Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), zinc K-edge X-ray absorption near edge structure (XANES), and Raman spectroscopies, showed that the unique structure, chemical state, and topology of ZIF-8 enable accessibility, adsorption, and hydrolysis of DMCP into the pores and revealed the importance of linker chemistry and Zn2+ sites for nerve agent decomposition. DMCP decontamination and decomposition product(s) formation were observed by thermogravimetric analysis, FT-IR spectroscopy, and phosphorus (P) K-edge XANES studies. Differential PDF analysis indicated that the average structure of ZIF-8 (at the 30 Å scale) remains unchanged after DMCP dosing and provided information on the dynamics of interactions of DMCP with the ZIF-8 framework. Using in situ PXRD and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), we showed that nearly 90% regeneration of the ZIF-8 structure and complete liberation of DMCP and decomposition products occur upon heating.
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Guo Y, Liu Z, Zhang F, Wang D, Yuan K, Huang L, Liu H, Senanayake SD, Rodriguez JA, Yan C, Zhang Y. Modulation of the Effective Metal‐Support Interactions for the Selectivity of Ceria Supported Noble Metal Nanoclusters in Atmospheric CO
2
Hydrogenation. ChemCatChem 2020. [DOI: 10.1002/cctc.202001531] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lustemberg PG, Zhang F, Gutiérrez RA, Ramírez PJ, Senanayake SD, Rodriguez JA, Ganduglia-Pirovano MV. Breaking Simple Scaling Relations through Metal-Oxide Interactions: Understanding Room-Temperature Activation of Methane on M/CeO 2 (M = Pt, Ni, or Co) Interfaces. J Phys Chem Lett 2020; 11:9131-9137. [PMID: 33052684 DOI: 10.1021/acs.jpclett.0c02109] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The clean activation of methane at low temperatures remains an eminent challenge and a field of competitive research. In particular, on late transition metal surfaces such as Pt(111) or Ni(111), higher temperatures are necessary to activate the hydrocarbon molecule, but a massive deposition of carbon makes the metal surface useless for catalytic activity. However, on very low-loaded M/CeO2 (M = Pt, Ni, or Co) surfaces, the dissociation of methane occurs at room temperature, which is unexpected considering simple linear scaling relationships. This intriguing phenomenon has been studied using a combination of experimental techniques (ambient-pressure X-ray photoelectron spectroscopy, time-resolved X-ray diffraction, and X-ray absorption spectroscopy) and density functional theory-based calculations. The experimental and theoretical studies show that the size and morphology of the supported nanoparticles together with strong metal-support interactions are behind the deviations from the scaling relations. These findings point toward a possible strategy for circumventing scaling relations, producing active and stable catalysts that can be employed for methane activation and conversion.
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Metavarayuth K, Ejegbavwo O, McCarver G, Myrick ML, Makris TM, Vogiatzis KD, Senanayake SD, Manley OM, Ebrahim AM, Frenkel AI, Hwang S, Rajeshkumar T, Jimenez JD, Chen K, Shustova NB, Chen DA. Direct Identification of Mixed-Metal Centers in Metal-Organic Frameworks: Cu 3(BTC) 2 Transmetalated with Rh 2+ Ions. J Phys Chem Lett 2020; 11:8138-8144. [PMID: 32894952 DOI: 10.1021/acs.jpclett.0c02539] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Raman spectroscopy was used to establish direct evidence of heterometallic metal centers in a metal-organic framework (MOF). The Cu3(BTC)2 MOF HKUST-1 (BTC3- = benzenetricarboxylate) was transmetalated by heating it in a solution of RhCl3 to substitute Rh2+ ions for Cu2+ ions in the dinuclear paddlewheel nodes of the framework. In addition to the Cu-Cu and Rh-Rh stretching modes, Raman spectra of (CuxRh1-x)3(BTC)2 show the Cu-Rh stretching mode, indicating that mixed-metal Cu-Rh nodes are formed after transmetalation. Density functional theory studies confirmed the assignment of a Raman peak at 285 cm-1 to the Cu-Rh stretching vibration. Electron paramagnetic resonance spectroscopy experiments further supported the conclusion that Rh2+ ions are substituted into the paddlewheel nodes of Cu3(BTC)2 to form an isostructural heterometallic MOF, and electron microscopy studies showed that Rh and Cu are homogeneously distributed in (CuxRh1-x)3(BTC)2 on the nanoscale.
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Senanayake SD, Rodriguez JA, Weaver JF. Low Temperature Activation of Methane on Metal-Oxides and Complex Interfaces: Insights from Surface Science. Acc Chem Res 2020; 53:1488-1497. [PMID: 32659076 DOI: 10.1021/acs.accounts.0c00194] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
ConspectusThe abundance of cheap, natural gas has transformed the energy landscape, whereby revealing new possibilities for sustainable chemical technologies or impacting those that have relied on traditional fossil fuels. The primary component, methane, is underutilized and wastefully exhausted, leading to anthropogenic global warming. Historically, the manipulation of methane remained "clavis aurea," an insurmountable yet rewarding challenge and thus the focus of intense research. This is primarily due to an inability to dissociate C-H bonds in methane selectively, which requires a high energy penalty and is an essential prerequisite for the direct conversion of methane into a large set of value-added products. The discovery of such processes would promise an energy gainful use of natural gas benefiting several essential chemical processes associated with C1 chemistry. This first C-H bond dissociation step of the methane molecule appears in numerous catalytic mechanisms as the rate-determining step or most essential barrier sequence for all subsequent steps that follow in the production of C-C, C-O, or Cx-Hy-Oz bonds found in value added products. A main goal is to catalytically reduce the energy barrier for the first C-H bond dissociation to be able to achieve the activation of methane at low or moderate temperatures. As such there is great value in understanding the fundamental nature of the active sites responsible for bond breaking or formation and thus be able to facilitate better control of this chemistry, leading to the development of new technologies for fuel production and chemical conversion. Surface science studies offer enhanced perspectives for a careful manipulation of bonds over the last layer atoms of catalyst surfaces, an essential factor for the design of atomically precise catalysts and unravelling of the reaction mechanism. With the advent of new surface imaging, spectroscopy, and in situ tools, it has been possible to decipher the surface chemistry of complex materials systems and further our understanding of atomic active sites on the surfaces of metals, oxides, and carbides or metal-oxide and metal-carbide interfaces. The once considered near impossible step of C-H bond activation is now observed at low temperatures with high propensity over a collection of oxide, metal-oxide, and metal-carbide systems in a conventional or inverse configuration (oxide or carbide on metal). The enabling of C-H activation at low temperature has opened interesting possibilities for the specific production of chemicals such as methanol directly from methane, a step toward facile synthesis of liquid fuels. We highlight the most recent of these results and present the key aspects of active site configurations engineered from surface science studies which enable such a simple reactive event through careful manipulation of the last surface layer of atoms found in the catalyst structure. New concepts which help in the activation and conversion of methane are discussed.
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Vovchok D, Zhang C, Hwang S, Jiao L, Zhang F, Liu Z, Senanayake SD, Rodriguez JA. Deciphering Dynamic Structural and Mechanistic Complexity in Cu/CeO2/ZSM-5 Catalysts for the Reverse Water-Gas Shift Reaction. ACS Catal 2020. [DOI: 10.1021/acscatal.0c01584] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Rui N, Zhang F, Sun K, Liu Z, Xu W, Stavitski E, Senanayake SD, Rodriguez JA, Liu CJ. Hydrogenation of CO2 to Methanol on a Auδ+–In2O3–x Catalyst. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02120] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Liu Z, Huang E, Orozco I, Liao W, Palomino RM, Rui N, Duchoň T, Nemšák S, Grinter DC, Mahapatra M, Liu P, Rodriguez JA, Senanayake SD. Water-promoted interfacial pathways in methane oxidation to methanol on a CeO 2-Cu 2O catalyst. Science 2020; 368:513-517. [PMID: 32355028 DOI: 10.1126/science.aba5005] [Citation(s) in RCA: 113] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 03/26/2020] [Indexed: 01/15/2023]
Abstract
Highly selective oxidation of methane to methanol has long been challenging in catalysis. Here, we reveal key steps for the pro-motion of this reaction by water when tuning the selectivity of a well-defined CeO2/Cu2O/Cu(111) catalyst from carbon monoxide and carbon dioxide to methanol under a reaction environment with methane, oxygen, and water. Ambient-pressure x-ray photoelectron spectroscopy showed that water added to methane and oxygen led to surface methoxy groups and accelerated methanol production. These results were consistent with density functional theory calculations and kinetic Monte Carlo simulations, which showed that water preferentially dissociates over the active cerium ions at the CeO2-Cu2O/Cu(111) interface. The adsorbed hydroxyl species blocked O-O bond cleavage that would dehydrogenate methoxy groups to carbon monoxide and carbon dioxide, and it directly converted this species to methanol, while oxygen reoxidized the reduced surface. Water adsorption also displaced the produced methanol into the gas phase.
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Ebrahim AM, Plonka AM, Tian Y, Senanayake SD, Gordon WO, Balboa A, Wang H, Collins-Wildman DL, Hill CL, Musaev DG, Morris JR, Troya D, Frenkel AI. Multimodal Characterization of Materials and Decontamination Processes for Chemical Warfare Protection. ACS APPLIED MATERIALS & INTERFACES 2020; 12:14721-14738. [PMID: 31815428 DOI: 10.1021/acsami.9b19494] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
This Review summarizes the recent progress made in the field of chemical threat reduction by utilizing new in situ analytical techniques and combinations thereof to study multifunctional materials designed for capture and decomposition of nerve gases and their simulants. The emphasis is on the use of in situ experiments that simulate realistic operating conditions (solid-gas interface, ambient pressures and temperatures, time-resolved measurements) and advanced synchrotron methods, such as in situ X-ray absorption and scattering methods, a combination thereof with other complementary measurements (e.g., XPS, Raman, DRIFTS, NMR), and theoretical modeling. The examples presented in this Review range from studies of the adsorption and decomposition of nerve agents and their simulants on Zr-based metal organic frameworks to Nb and Zr-based polyoxometalates and metal (hydro)oxide materials. The approaches employed in these studies ultimately demonstrate how advanced synchrotron-based in situ X-ray absorption spectroscopy and diffraction can be exploited to develop an atomic- level understanding of interfacial binding and reaction of chemical warfare agents, which impacts the development of novel filtration media and other protective materials.
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Kang J, Mahapatra M, Rui N, Orozco I, Shi R, Senanayake SD, Rodriguez JA. Growth and structural studies of In/Au(111) alloys and InO x/Au(111) inverse oxide/metal model catalysts. J Chem Phys 2020; 152:054702. [PMID: 32035457 DOI: 10.1063/1.5139237] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Indium oxide has received attention as an exciting candidate for catalyzing the CO2 hydrogenation to methanol due to its high selectivity (>80%). Compared to the extent of research on the activity of indium oxide-based powder catalysts, very little is known about the phenomena associated with the formation of surface alloys involving indium or the growth mechanism for indium oxide nanoparticles. In this report, scanning tunneling microscopy and X-ray photoelectron spectroscopy (XPS) were employed to elucidate the growth mode, structure, and chemical state of In/Au(111) alloys and InOx/Au(111) inverse model catalysts. Our study reveals distinct morphological differences between In/Au(111) and InOx/Au(111), and the InOx structure also depends strongly on the preparation conditions. In/Au surface alloy systems with extremely low coverage (0.02 ML) form islands preferentially on the elbow sites of reconstructed Au(111) herringbone, regardless of hexagonally closed packed and face centered cubic stacking. At higher coverage (0.1 ML), the In islands expand over the herringbone in the ⟨110⟩ direction and create two dimensional domain structures over the entire surfaces. Moreover, this 2D domain structure is disturbed by temperature with high dispersion of indium atoms observed during the annealing process. Oxidation of the In/Au(111) surface alloys with O2 at 550 K produces InOx/Au(111) systems which contain various sizes of InOx aggregates (from 0.7 nm to 10 nm). On the other hand, InOx/Au(111) surfaces prepared by vapor deposition of In at 550 K in an O2 background exhibit highly dispersed and uniformly small InOx particles (∼1 nm). Both InOx systems were confirmed to be partially oxidized by XPS.
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Hamlyn R, Mahapatra M, Orozco I, Hunt A, Waluyo I, White MG, Senanayake SD, Rodriguez J. Morphology and chemical behavior of model CsOx/Cu2O/Cu(111) nanocatalysts for methanol synthesis: Reaction with CO2 and H2. J Chem Phys 2020; 152:044701. [DOI: 10.1063/1.5129152] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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Zhang F, Liu Z, Chen X, Rui N, Betancourt LE, Lin L, Xu W, Sun CJ, Abeykoon AMM, Rodriguez JA, Teržan J, Lorber K, Djinović P, Senanayake SD. Effects of Zr Doping into Ceria for the Dry Reforming of Methane over Ni/CeZrO2 Catalysts: In Situ Studies with XRD, XAFS, and AP-XPS. ACS Catal 2020. [DOI: 10.1021/acscatal.9b04451] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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38
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Deng K, Lin L, Rui N, Vovchok D, Zhang F, Zhang S, Senanayake SD, Kim T, Rodriguez JA. Studies of CO2 hydrogenation over cobalt/ceria catalysts with in situ characterization: the effect of cobalt loading and metal–support interactions on the catalytic activity. Catal Sci Technol 2020. [DOI: 10.1039/d0cy00962h] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Metal–oxide interactions affect the catalytic properties of Co/CeO2 and can be used to control activity and selectivity.
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Rodriguez JA, Remesal ER, Ramírez PJ, Orozco I, Liu Z, Graciani J, Senanayake SD, Sanz JF. Water–Gas Shift Reaction on K/Cu(111) and Cu/K/TiO2(110) Surfaces: Alkali Promotion of Water Dissociation and Production of H2. ACS Catal 2019. [DOI: 10.1021/acscatal.9b03922] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Shakya DM, Ejegbavwo OA, Rajeshkumar T, Senanayake SD, Brandt AJ, Farzandh S, Acharya N, Ebrahim AM, Frenkel AI, Rui N, Tate GL, Monnier JR, Vogiatzis KD, Shustova NB, Chen DA. Selective Catalytic Chemistry at Rhodium(II) Nodes in Bimetallic Metal–Organic Frameworks. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201908761] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Shakya DM, Ejegbavwo OA, Rajeshkumar T, Senanayake SD, Brandt AJ, Farzandh S, Acharya N, Ebrahim AM, Frenkel AI, Rui N, Tate GL, Monnier JR, Vogiatzis KD, Shustova NB, Chen DA. Selective Catalytic Chemistry at Rhodium(II) Nodes in Bimetallic Metal-Organic Frameworks. Angew Chem Int Ed Engl 2019; 58:16533-16537. [PMID: 31529667 DOI: 10.1002/anie.201908761] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 08/15/2019] [Indexed: 11/06/2022]
Abstract
We report the first study of a gas-phase reaction catalyzed by highly dispersed sites at the metal nodes of a crystalline metal-organic framework (MOF). Specifically, CuRhBTC (BTC3- =benzenetricarboxylate) exhibited hydrogenation activity, while other isostructural monometallic and bimetallic MOFs did not. Our multi-technique characterization identifies the oxidation state of Rh in CuRhBTC as +2, which is a Rh oxidation state that has not previously been observed for crystalline MOF metal nodes. These Rh2+ sites are active for the catalytic hydrogenation of propylene to propane at room temperature, and the MOF structure stabilizes the Rh2+ oxidation state under reaction conditions. Density functional theory calculations suggest a mechanism in which hydrogen dissociation and propylene adsorption occur at the Rh2+ sites. The ability to tailor the geometry and ensemble size of the metal nodes in MOFs allows for unprecedented control of the active sites and could lead to significant advances in rational catalyst design.
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Kottwitz M, Li Y, Palomino RM, Liu Z, Wang G, Wu Q, Huang J, Timoshenko J, Senanayake SD, Balasubramanian M, Lu D, Nuzzo RG, Frenkel AI. Local Structure and Electronic State of Atomically Dispersed Pt Supported on Nanosized CeO2. ACS Catal 2019. [DOI: 10.1021/acscatal.9b02083] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Kettner M, Duchoň T, Wolf MJ, Kullgren J, Senanayake SD, Hermansson K, Veltruská K, Nehasil V. Anion-mediated electronic effects in reducible oxides: Tuning the valence band of ceria via fluorine doping. J Chem Phys 2019; 151:044701. [PMID: 31370552 DOI: 10.1063/1.5109955] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Combining experimental spectroscopy and hybrid density functional theory calculations, we show that the incorporation of fluoride ions into a prototypical reducible oxide surface, namely, ceria(111), can induce a variety of nontrivial changes to the local electronic structure, beyond the expected increase in the number of Ce3+ ions. Our resonant photoemission spectroscopy results reveal new states above, within, and below the valence band, which are unique to the presence of fluoride ions at the surface. With the help of hybrid density functional calculations, we show that the different states arise from fluoride ions in different atomic layers in the near surface region. In particular, we identify a structure in which a fluoride ion substitutes for an oxygen ion at the surface, with a second fluoride ion on top of a surface Ce4+ ion giving rise to F 2p states which overlap the top of the O 2p band. The nature of this adsorbate F--Ce4+ resonant enhancement feature suggests that this bond is at least partially covalent. Our results demonstrate the versatility of anion doping as a potential means of tuning the valence band electronic structure of ceria.
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Yao S, Lin L, Liao W, Rui N, Li N, Liu Z, Cen J, Zhang F, Li X, Song L, Betancourt De Leon L, Su D, Senanayake SD, Liu P, Ma D, Chen JG, Rodriguez JA. Exploring Metal–Support Interactions To Immobilize Subnanometer Co Clusters on γ–Mo2N: A Highly Selective and Stable Catalyst for CO2 Activation. ACS Catal 2019. [DOI: 10.1021/acscatal.9b01945] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Tian Y, Plonka AM, Ebrahim AM, Palomino RM, Senanayake SD, Balboa A, Gordon WO, Troya D, Musaev DG, Morris JR, Mitchell MB, Collins-Wildman DL, Hill CL, Frenkel AI. Correlated Multimodal Approach Reveals Key Details of Nerve-Agent Decomposition by Single-Site Zr-Based Polyoxometalates. J Phys Chem Lett 2019; 10:2295-2299. [PMID: 31002759 DOI: 10.1021/acs.jpclett.9b01002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Development of technologies for protection against chemical warfare agents (CWAs) is critically important. Recently, polyoxometalates have attracted attention as potential catalysts for nerve-agent decomposition. Improvement of their effectiveness in real operating conditions requires an atomic-level understanding of CWA decomposition at the gas-solid interface. We investigated decomposition of the nerve agent Sarin and its simulant, dimethyl chlorophosphate (DMCP), by zirconium polytungstate. Using a multimodal approach, we showed that upon DMCP and Sarin exposure the dimeric tungstate undergoes monomerization, making coordinatively unsaturated Zr(IV) centers available, which activate nucleophilic hydrolysis. Further, DMCP is shown to be a good model system of reduced toxicity for studies of CWA deactivation at the gas-solid interface.
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Liu Z, Zhang F, Rui N, Li X, Lin L, Betancourt LE, Su D, Xu W, Cen J, Attenkofer K, Idriss H, Rodriguez JA, Senanayake SD. Highly Active Ceria-Supported Ru Catalyst for the Dry Reforming of Methane: In Situ Identification of Ruδ+–Ce3+ Interactions for Enhanced Conversion. ACS Catal 2019. [DOI: 10.1021/acscatal.8b05162] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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47
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Vovchok D, Tata J, Orozco I, Zhang F, Palomino RM, Xu W, Harper L, Khatib SJ, Rodriguez JA, Senanayake SD. Location and chemical speciation of Cu in ZSM-5 during the water-gas shift reaction. Catal Today 2019. [DOI: 10.1016/j.cattod.2018.07.049] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Lin L, Yao S, Rui N, Han L, Zhang F, Gerlak CA, Liu Z, Cen J, Song L, Senanayake SD, Xin HL, Chen JG, Rodriguez JA. Conversion of CO2 on a highly active and stable Cu/FeOx/CeO2 catalyst: tuning catalytic performance by oxide-oxide interactions. Catal Sci Technol 2019. [DOI: 10.1039/c9cy00722a] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Oxide–oxide interactions have been used to control textural properties and produce active and stable Cu/FeOx/CeO2 catalysts.
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Flege JI, Höcker J, Sadowski JT, Senanayake SD, Falta J. Nucleation, morphology, and structure of sub‐nm thin ceria islands on Rh(111). SURF INTERFACE ANAL 2018. [DOI: 10.1002/sia.6567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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50
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Liu Z, Yao S, Johnston-Peck A, Xu W, Rodriguez JA, Senanayake SD. Methanol steam reforming over Ni-CeO2 model and powder catalysts: Pathways to high stability and selectivity for H2/CO2 production. Catal Today 2018. [DOI: 10.1016/j.cattod.2017.08.041] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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