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Meledina M, Krishnan D, Ozsoy-Keskinbora C, Heidari H, Wu X, Simon U, Lazar S, Tiemeijer P, Longo P. Multimodal EELS and EDX Spectroscopy in 2D and 3D for Analysis of Catalysts at the Nanoscale. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:1983-1984. [PMID: 37612951 DOI: 10.1093/micmic/ozad067.1027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Maria Meledina
- Thermo Fisher Scientific, Materials & Structural Analysis, Eindhoven, the Netherlands
| | - Dileep Krishnan
- Thermo Fisher Scientific, Materials & Structural Analysis, Eindhoven, the Netherlands
| | | | - Hamed Heidari
- Thermo Fisher Scientific, Materials & Structural Analysis, Eindhoven, the Netherlands
| | - Xiaochao Wu
- Institute of Inorganic Chemistry, RWTH Aachen University, Aachen, Germany
- Center for Automotive Catalytic Systems Aachen, RWTH Aachen University, Aachen, Germany
| | - Ulrich Simon
- Institute of Inorganic Chemistry, RWTH Aachen University, Aachen, Germany
- Center for Automotive Catalytic Systems Aachen, RWTH Aachen University, Aachen, Germany
| | - Sorin Lazar
- Thermo Fisher Scientific, Materials & Structural Analysis, Eindhoven, the Netherlands
| | - Peter Tiemeijer
- Thermo Fisher Scientific, Materials & Structural Analysis, Eindhoven, the Netherlands
| | - Paolo Longo
- Thermo Fisher Scientific, Materials & Structural Analysis, Eindhoven, the Netherlands
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2
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Effect of doping of iron on structural, optical and magnetic properties of CeO2 nanoparticles. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.140110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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3
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Reverse Water Gas Shift by Chemical Looping with Iron-Substituted Hexaaluminate Catalysts. Catalysts 2020. [DOI: 10.3390/catal10091082] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The Fe-substituted Ba-hexaaluminates (BaFeHAl) are active catalysts for reverse water-gas shift (RWGS) reaction conducted in chemical looping mode. Increasing of the degree of substitution of Al3+ for Fe3+ ions in co-precipitated BaHAl from 60% (BaFeHAl) to 100% (BaFe-hexaferrite, BaFeHF), growing its surface area from 5 to 30 m2/g, and promotion with potassium increased the CO capacity in isothermal RWGS-CL runs at 350–450 °C, where the hexaaluminate/hexaferrite structure is stable. Increasing H2-reduction temperature converts BaFeHAl to a thermally stable BaFeHF modification that contains additional Ba-O-Fe bridges in its structure, reinforcing the connection between alternatively stacked spinel blocks. This material displayed the highest CO capacity of 400 µmol/g at isothermal RWGS-CL run conducted at 550 °C due to increased concentration of oxygen vacancies reflected by greater surface Fe2+/Fe3+ ratio detected by XPS. The results demonstrate direct connection between CO capacity measured in RWGS-CL experiments and calculated CO2 conversion.
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4
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Gokcekaya O, Ueda K, Narushima T, Nakano T. Using HAADF-STEM for atomic-scale evaluation of incorporation of antibacterial Ag atoms in a β-tricalcium phosphate structure. NANOSCALE 2020; 12:16596-16604. [PMID: 32756641 DOI: 10.1039/d0nr04208k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Structural evaluation of ionic additions in calcium phosphates that enhance their performance is a long-lasting area of research in the field of biomedical materials. Ionic incorporation in β-tricalcium phosphate (β-TCP) structures is indispensable for obtaining desirable properties for specific functions and applications. Owing to its complex structure and beam-sensitive nature, determining the extent of ion incorporation and its corresponding location in the β-TCP structure is challenging. Further, very few experimental studies have been able to estimate the location of Ag atoms incorporated in a β-TCP structure while considering the associated changes in lattice parameters. Although the incorporation alters the lattice parameters, the alteration is not significant enough for estimating the location of the incorporated Ag atoms. Here, Ag incorporation in a β-TCP structure was evaluated on atomic scale using scanning transmission electron microscopy (STEM). To the best of our knowledge, this is the first report to unambiguously determine the location of the incorporated Ag atoms in the β-TCP structure by comparing z-contrast profiles of the Ag and Ca atoms by combining the state-of-art STEM observations and STEM image simulations. The Ag incorporation in the Ca(4) sites of β-TCP, as estimated by the Rietveld refinement, was in good agreement with the high-angle annular dark-field STEM observations and the simulations of the location of Ag atoms for [001] and [010] zone axes.
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Affiliation(s)
- Ozkan Gokcekaya
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
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5
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Abstract
Methane activation chemistry, despite being widely reported in literature, remains to date a subject of debate. The challenges in this reaction are not limited to methane activation but extend to stabilization of the intermediate species. The low C-H dissociation energy of intermediates vs. reactants leads to CO2 formation. For selective oxidation, nature presents methane monooxygenase as a benchmark. This enzyme selectively consumes methane by breaking it down into methanol. To assemble an active site similar to monooxygenase, the literature reports Cu-ZSM-5, Fe-ZSM-5, and Cu-MOR, using zeolites and systems like CeO2/Cu2O/Cu. However, the trade-off between methane activation and methanol selectivity remains a challenge. Density functional theory (DFT) calculations and spectroscopic studies indicate catalyst reducibility, oxygen mobility, and water as co-feed as primary factors that can assist in enabling higher selectivity. The use of chemical looping can further improve selectivity. However, in all systems, improvements in productivity per cycle are required in order to meet the economical/industrial standards.
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6
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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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Affiliation(s)
- Lili Lin
- Chemistry Department
- Brookhaven National Laboratory
- Upton
- USA
| | - Siyu Yao
- Chemistry Department
- Brookhaven National Laboratory
- Upton
- USA
| | - Ning Rui
- Chemistry Department
- Brookhaven National Laboratory
- Upton
- USA
| | - Lili Han
- Department of Physics and Astronomy
- University of California
- Irvine
- USA
| | - Feng Zhang
- Materials Science and Chemical Engineering Department
- State University of New York
- Stony Brook
- USA
| | | | - Zongyuan Liu
- Chemistry Department
- Brookhaven National Laboratory
- Upton
- USA
| | - Jiajie Cen
- Materials Science and Chemical Engineering Department
- State University of New York
- Stony Brook
- USA
| | - Liang Song
- Materials Science and Chemical Engineering Department
- State University of New York
- Stony Brook
- USA
| | | | - Huolin L. Xin
- Department of Physics and Astronomy
- University of California
- Irvine
- USA
| | | | - José A. Rodriguez
- Chemistry Department
- Brookhaven National Laboratory
- Upton
- USA
- Materials Science and Chemical Engineering Department
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7
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Fe-Based Nano-Materials in Catalysis. MATERIALS 2018; 11:ma11050831. [PMID: 29772842 PMCID: PMC5978208 DOI: 10.3390/ma11050831] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 05/04/2018] [Accepted: 05/10/2018] [Indexed: 01/29/2023]
Abstract
The role of iron in view of its further utilization in chemical processes is presented, based on current knowledge of its properties. The addition of iron to a catalyst provides redox functionality, enhancing its resistance to carbon deposition. FeOx species can be formed in the presence of an oxidizing agent, such as CO2, H2O or O2, during reaction, which can further react via a redox mechanism with the carbon deposits. This can be exploited in the synthesis of active and stable catalysts for several processes, such as syngas and chemicals production, catalytic oxidation in exhaust converters, etc. Iron is considered an important promoter or co-catalyst, due to its high availability and low toxicity that can enhance the overall catalytic performance. However, its operation is more subtle and diverse than first sight reveals. Hence, iron and its oxides start to become a hot topic for more scientists and their findings are most promising. The scope of this article is to provide a review on iron/iron-oxide containing catalytic systems, including experimental and theoretical evidence, highlighting their properties mainly in view of syngas production, chemical looping, methane decomposition for carbon nanotubes production and propane dehydrogenation, over the last decade. The main focus goes to Fe-containing nano-alloys and specifically to the Fe–Ni nano-alloy, which is a very versatile material.
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8
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Zhu X, Zhang M, Li K, Wei Y, Zheng Y, Hu J, Wang H. Chemical-looping water splitting over ceria-modified iron oxide: Performance evolution and element migration during redox cycling. Chem Eng Sci 2018. [DOI: 10.1016/j.ces.2018.01.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Dharanipragada N, Galvita VV, Poelman H, Buelens LC, Marin GB, Longo A. Insight in kinetics from pre-edge features using time resolved in situ
XAS. AIChE J 2017. [DOI: 10.1002/aic.16017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- N.V.R.A. Dharanipragada
- Dept. of Materials, Textiles and Chemical Engineering, Laboratory for Chemical Technology; Ghent University, Technologiepark 914; B-9052 Ghent Belgium
| | - Vladimir V. Galvita
- Dept. of Materials, Textiles and Chemical Engineering, Laboratory for Chemical Technology; Ghent University, Technologiepark 914; B-9052 Ghent Belgium
| | - Hilde Poelman
- Dept. of Materials, Textiles and Chemical Engineering, Laboratory for Chemical Technology; Ghent University, Technologiepark 914; B-9052 Ghent Belgium
| | - Lukas C. Buelens
- Dept. of Materials, Textiles and Chemical Engineering, Laboratory for Chemical Technology; Ghent University, Technologiepark 914; B-9052 Ghent Belgium
| | - Guy B. Marin
- Dept. of Materials, Textiles and Chemical Engineering, Laboratory for Chemical Technology; Ghent University, Technologiepark 914; B-9052 Ghent Belgium
| | - Alessandro Longo
- Institution Netherlands Organization for Scientific Research (NWO); The European Synchrotron, CS40220, 38043, 71 Avenue des Martyrs; 38000 Grenoble France
- Istituto per lo Studio dei Materiali Nanostrutturati (ISMN); CNR, UOS Palermo, Via Ugo La Malfa, 153; 90146 Palermo Italy
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10
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Oxygen uptake, selectivity and reversibility of Tb–CeO2 mixed oxides for air separation. ADSORPTION 2017. [DOI: 10.1007/s10450-016-9855-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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11
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Goris B, Meledina M, Turner S, Zhong Z, Batenburg KJ, Bals S. Three dimensional mapping of Fe dopants in ceria nanocrystals using direct spectroscopic electron tomography. Ultramicroscopy 2016; 171:55-62. [DOI: 10.1016/j.ultramic.2016.08.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 08/22/2016] [Accepted: 08/29/2016] [Indexed: 11/26/2022]
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12
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Chong S, Zhang G, Zhang N, Liu Y, Zhu J, Huang T, Fang S. Preparation of FeCeOx by ultrasonic impregnation method for heterogeneous Fenton degradation of diclofenac. ULTRASONICS SONOCHEMISTRY 2016; 32:231-240. [PMID: 27150766 DOI: 10.1016/j.ultsonch.2016.03.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 03/19/2016] [Accepted: 03/19/2016] [Indexed: 05/20/2023]
Abstract
FeCeOx has been successfully synthesized by ultrasonic impregnation method and applied in diclofenac removal in heterogeneous Fenton process. The effects of ultrasonic density, impregnation time, mole ratio of Fe and Ce and calcination temperature were investigated. Nitrogen adsorption/desorption, SEM, XRD, HRTEM, Raman and XPS analyses were characterized. Stability and reusability of FeCeOx were evaluated. The results indicated that 83% degradation efficiency of diclofenac was achieved by FeCeOx under the optimum preparation conditions. Fe ions were distributed uniformly in crystal structure and the solid solution structure of FeCeOx with a lattice constriction was formed. Exposed crystalline plane (200) with a relatively high surface energy may be the main reason to provide high catalytic activity of FeCeOx. Oxygen vacancies took part in catalytic process and a portion of them were oxidized after reaction. FeCeOx showed an excellent chemical stability and reusability in heterogeneous Fenton process.
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Affiliation(s)
- Shan Chong
- School of Environment & Natural Resource, Renmin University of China, Beijing 100872, China.
| | - Guangming Zhang
- School of Environment & Natural Resource, Renmin University of China, Beijing 100872, China.
| | - Nan Zhang
- School of Environment & Natural Resource, Renmin University of China, Beijing 100872, China.
| | - Yucan Liu
- School of Environment & Natural Resource, Renmin University of China, Beijing 100872, China.
| | - Jia Zhu
- School of Construction and Environment Engineering, Shenzhen Polytechnic, Shenzhen 518055, China.
| | - Ting Huang
- School of Environment & Natural Resource, Renmin University of China, Beijing 100872, China.
| | - Shunyan Fang
- School of Environment & Natural Resource, Renmin University of China, Beijing 100872, China.
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13
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Dharanipragada NVRA, Meledina M, Galvita VV, Poelman H, Turner S, Van Tendeloo G, Detavernier C, Marin GB. Deactivation Study of Fe2O3–CeO2 during Redox Cycles for CO Production from CO2. Ind Eng Chem Res 2016. [DOI: 10.1021/acs.iecr.6b00963] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Maria Meledina
- Electron
Microscopy for Materials Science (EMAT), Department of Physics, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Vladimir V. Galvita
- Laboratory
for Chemical Technology, Ghent University, Technologiepark 914, B-9052 Gent, Belgium
| | - Hilde Poelman
- Laboratory
for Chemical Technology, Ghent University, Technologiepark 914, B-9052 Gent, Belgium
| | - Stuart Turner
- Electron
Microscopy for Materials Science (EMAT), Department of Physics, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Gustaaf Van Tendeloo
- Electron
Microscopy for Materials Science (EMAT), Department of Physics, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Christophe Detavernier
- Department
of Solid State Sciences, Ghent University, Krijgslaan 281, S1, B-9000 Ghent, Belgium
| | - Guy B. Marin
- Laboratory
for Chemical Technology, Ghent University, Technologiepark 914, B-9052 Gent, Belgium
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14
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Jampaiah D, Srinivasa Reddy T, Kandjani AE, Selvakannan PR, Sabri YM, Coyle VE, Shukla R, Bhargava SK. Fe-doped CeO2 nanorods for enhanced peroxidase-like activity and their application towards glucose detection. J Mater Chem B 2016; 4:3874-3885. [DOI: 10.1039/c6tb00422a] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Surface defects of Fe-doped CeO2 nanorods were found to be active sites for increasing peroxidase mimetic activity.
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Affiliation(s)
- Deshetti Jampaiah
- Centre for Advanced Materials & Industrial Chemistry (CAMIC)
- School of Applied Sciences
- RMIT University
- Melbourne-3001
- Australia
| | - T. Srinivasa Reddy
- Centre for Advanced Materials & Industrial Chemistry (CAMIC)
- School of Applied Sciences
- RMIT University
- Melbourne-3001
- Australia
| | - Ahmad Esmaielzadeh Kandjani
- Centre for Advanced Materials & Industrial Chemistry (CAMIC)
- School of Applied Sciences
- RMIT University
- Melbourne-3001
- Australia
| | - P. R. Selvakannan
- Centre for Advanced Materials & Industrial Chemistry (CAMIC)
- School of Applied Sciences
- RMIT University
- Melbourne-3001
- Australia
| | - Ylias M. Sabri
- Centre for Advanced Materials & Industrial Chemistry (CAMIC)
- School of Applied Sciences
- RMIT University
- Melbourne-3001
- Australia
| | - Victoria E. Coyle
- Centre for Advanced Materials & Industrial Chemistry (CAMIC)
- School of Applied Sciences
- RMIT University
- Melbourne-3001
- Australia
| | - Ravi Shukla
- Nanobiotechnology Research Laboratory
- School of Applied Sciences
- RMIT University
- Melbourne-3001
- Australia
| | - Suresh K. Bhargava
- Centre for Advanced Materials & Industrial Chemistry (CAMIC)
- School of Applied Sciences
- RMIT University
- Melbourne-3001
- Australia
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15
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Menon U, Galvita VV, Constales D, Alexopoulos K, Yablonsky G, Marin GB. Microkinetics for toluene total oxidation over CuO–CeO2/Al2O3. Catal Today 2015. [DOI: 10.1016/j.cattod.2015.07.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Substitutional doping in nanocrystal superlattices. Nature 2015; 524:450-3. [PMID: 26310766 DOI: 10.1038/nature14872] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 06/26/2015] [Indexed: 01/26/2023]
Abstract
Doping is a process in which atomic impurities are intentionally added to a host material to modify its properties. It has had a revolutionary impact in altering or introducing electronic, magnetic, luminescent, and catalytic properties for several applications, for example in semiconductors. Here we explore and demonstrate the extension of the concept of substitutional atomic doping to nanometre-scale crystal doping, in which one nanocrystal is used to replace another to form doped self-assembled superlattices. Towards this goal, we show that gold nanocrystals act as substitutional dopants in superlattices of cadmium selenide or lead selenide nanocrystals when the size of the gold nanocrystal is very close to that of the host. The gold nanocrystals occupy random positions in the superlattice and their density is readily and widely controllable, analogous to the case of atomic doping, but here through nanocrystal self-assembly. We also show that the electronic properties of the superlattices are highly tunable and strongly affected by the presence and density of the gold nanocrystal dopants. The conductivity of lead selenide films, for example, can be manipulated over at least six orders of magnitude by the addition of gold nanocrystals and is explained by a percolation model. As this process relies on the self-assembly of uniform nanocrystals, it can be generally applied to assemble a wide variety of nanocrystal-doped structures for electronic, optical, magnetic, and catalytic materials.
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