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Huang J, Klahn M, Tian X, Bartling S, Zimina A, Radtke M, Rockstroh N, Naliwajko P, Steinfeldt N, Peppel T, Grunwaldt JD, Logsdail AJ, Jiao H, Strunk J. Fundamental Structural and Electronic Understanding of Palladium Catalysts on Nitride and Oxide Supports. Angew Chem Int Ed Engl 2024:e202400174. [PMID: 38466808 DOI: 10.1002/anie.202400174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/16/2024] [Accepted: 02/22/2024] [Indexed: 03/13/2024]
Abstract
The nature of the support can fundamentally affect the function of a heterogeneous catalyst. For the novel type of isolated metal atom catalysts, sometimes referred to as single-atom catalysts, systematic correlations are still rare. Here, we report a general finding that Pd on nitride supports (non-metal and metal nitride) features a higher oxidation state compared to that on oxide supports (non-metal and metal oxide). Through thorough oxidation state investigations by X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS), CO-DRIFTS, and density functional theory (DFT) coupled with Bader charge analysis, it is found that Pd atoms prefer to interact with surface hydroxyl group to form a Pd(OH)x species on oxide supports, while on nitride supports, Pd atoms incorporate into the surface structure in the form of Pd-N bonds. Moreover, a correlation was built between the formal oxidation state and computational Bader charge, based on the periodic trend in electronegativity.
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Affiliation(s)
- Junhao Huang
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Marcus Klahn
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Xinxin Tian
- Institute of Molecular Science, Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province, Key Laboratory of Chemical Biology and Molecular Engineering of Education Ministry, Shanxi University, Taiyuan, 030006, China
| | - Stephan Bartling
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Anna Zimina
- Institute of Catalysis Research and Technology and Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Martin Radtke
- Federal Institute for Materials Research and Testing (BAM), Richard-Willstätter-Str. 11, 12489, Berlin, Germany
| | - Nils Rockstroh
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Pawel Naliwajko
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Norbert Steinfeldt
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Tim Peppel
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Jan-Dierk Grunwaldt
- Institute of Catalysis Research and Technology and Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Andrew J Logsdail
- Max Planck-Cardiff Centre on the Fundamentals of Heterogeneous Catalysis (FUNCAT), Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT, United Kingdom
| | - Haijun Jiao
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Jennifer Strunk
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059, Rostock, Germany
- Industrial Chemistry and Heterogeneous Catalysis, Technical University of Munich, Lichtenbergstrße 4, 85748, Garching, Germany
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2
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Sebek M, Krake EF, Baumann W, Strunk J, Steinfeldt N. Effect of atmosphere and relative humidity on photodegradation of clopidogrel under artificial solar and indoor light irradiation. J Pharm Biomed Anal 2023; 234:115506. [PMID: 37311375 DOI: 10.1016/j.jpba.2023.115506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/08/2023] [Accepted: 06/04/2023] [Indexed: 06/15/2023]
Abstract
Knowledge of the chemical stability of active pharmaceutical ingredients (APIs) is an important issue in the drug development process. This work describes a methodical approach and a comprehensive protocol for forced photodegradation studies of solid clopidogrel hydrogen sulfate (Clp) under artificial sunlight and indoor irradiation at different relative humidities (RHs) and atmospheres. The results showed that, at low RHs (up to 21%), this API was relatively resistant to simulated sunlight as well as indoor light. However, at higher RHs (between 52% and 100%), more degradation products were formed, and the degradation rate increased with rising RH. The influence of oxygen on the degradation was relatively low, and most degradation reactions proceeded even in humid argon atmosphere. The photodegradation products (DP) were analyzed with two different HPLC systems (LC-UV, LC-UV-MS) and selected impurities were separated by a semi-preparative HPLC and identified by high resolution mass spectrometry (ESI-TOF-MS) and 1H NMR techniques. Based on the obtained results, a light induced degradation pathway could be proposed for Clp in solid state.
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Affiliation(s)
- Michael Sebek
- Leibniz-Institut für Katalyse e.V., Albert-Einstein-Str. 29a, 18059 Rostock, Germany
| | - Everaldo F Krake
- Leibniz-Institut für Katalyse e.V., Albert-Einstein-Str. 29a, 18059 Rostock, Germany
| | - Wolfgang Baumann
- Leibniz-Institut für Katalyse e.V., Albert-Einstein-Str. 29a, 18059 Rostock, Germany
| | - Jennifer Strunk
- Leibniz-Institut für Katalyse e.V., Albert-Einstein-Str. 29a, 18059 Rostock, Germany
| | - Norbert Steinfeldt
- Leibniz-Institut für Katalyse e.V., Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
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3
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Wang C, Azofra LM, Dam P, Sebek M, Steinfeldt N, Rabeah J, El-Sepelgy O. Catalytic Desaturation of Aliphatic Amides and Imides Enabled by Excited-State Base-Metal Catalysis. ACS Catal 2022. [DOI: 10.1021/acscatal.2c01723] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Chenyang Wang
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059 Rostock, Germany
| | - Luis Miguel Azofra
- Instituto de Estudios Ambientales y Recursos Naturales (i-UNAT), Universidad de Las Palmas de Gran Canaria (ULPGC), Campus de Tafira, 35017 Las Palmas de Gran Canaria, Spain
| | - Phong Dam
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059 Rostock, Germany
| | - Michael Sebek
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059 Rostock, Germany
| | - Norbert Steinfeldt
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059 Rostock, Germany
| | - Jabor Rabeah
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059 Rostock, Germany
| | - Osama El-Sepelgy
- Leibniz Institute for Catalysis e.V., Albert-Einstein-Straße 29a, 18059 Rostock, Germany
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Vu VT, Bartling S, Peppel T, Lund H, Kreyenschulte C, Rabeah J, Moustakas NG, Surkus AE, Ta HD, Steinfeldt N. Enhanced photocatalytic performance of polymeric carbon nitride through combination of iron loading and hydrogen peroxide treatment. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2019.124383] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Steinfeldt N, Kockmann N. Experimental and Numerical Characterization of Transport Phenomena in a Falling Film Microreactor with Gas–Liquid Reaction. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.9b04154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Norbert Steinfeldt
- Leibniz-Institut für Katalyse e.V., Albert-Einstein-Straße 29a, 18069 Rostock, Germany
| | - Norbert Kockmann
- Department of Biochemical and Chemical Engineering, Equipment Design, TU Dortmund, Emil-Figge-Straße 68, 44227 Dortmund, Germany
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Konrath R, Heutz FJL, Steinfeldt N, Rockstroh N, Kamer PCJ. Facile synthesis of supported Ru-Triphos catalysts for continuous flow application in selective nitrile reduction. Chem Sci 2019; 10:8195-8201. [PMID: 31857885 PMCID: PMC6837175 DOI: 10.1039/c9sc01415b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 07/22/2019] [Indexed: 11/24/2022] Open
Abstract
Selectivity of immobilized Triphos-type catalysts can be tuned for application in nitrile hydrogenation in batch and continuous flow processes.
The selective catalytic hydrogenation of nitriles represents an important but challenging transformation for many homogeneous and heterogeneous catalysts. Herein, we report the efficient and modular solid-phase synthesis of immobilized Triphos-type ligands in very high yields, involving only minimal work-up procedures. The corresponding supported ruthenium–Triphos catalysts are tested in the hydrogenation of various nitriles. Under mild conditions and without the requirement of additives, the tunable supported catalyst library provides selective access to both primary amines and secondary imines. Moreover, the first application of a Triphos-type catalyst in a continuous flow process is presented demonstrating high catalyst life-time over at least 195 hours without significant activity loss.
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Affiliation(s)
- Robert Konrath
- School of Chemistry , University of St Andrews , North Haugh , St Andrews , Fife KY16 9ST , UK . .,Leibniz-Institut für Katalyse e. V. an der Universität Rostock , Albert-Einstein Straße 29a , 18059 Rostock , Germany .
| | - Frank J L Heutz
- School of Chemistry , University of St Andrews , North Haugh , St Andrews , Fife KY16 9ST , UK .
| | - Norbert Steinfeldt
- Leibniz-Institut für Katalyse e. V. an der Universität Rostock , Albert-Einstein Straße 29a , 18059 Rostock , Germany .
| | - Nils Rockstroh
- Leibniz-Institut für Katalyse e. V. an der Universität Rostock , Albert-Einstein Straße 29a , 18059 Rostock , Germany .
| | - Paul C J Kamer
- Leibniz-Institut für Katalyse e. V. an der Universität Rostock , Albert-Einstein Straße 29a , 18059 Rostock , Germany .
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Parnicka P, Grzyb T, Mikolajczyk A, Wang K, Kowalska E, Steinfeldt N, Klein M, Mazierski P, Zaleska-Medynska A, Nadolna J. Experimental and theoretical investigations of the influence of carbon on a Ho 3+-TiO 2 photocatalyst with Vis response. J Colloid Interface Sci 2019; 549:212-224. [PMID: 31039457 DOI: 10.1016/j.jcis.2019.04.074] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 04/23/2019] [Accepted: 04/24/2019] [Indexed: 11/16/2022]
Abstract
Due to their photon up-converting capability, lanthanide ions are ideal candidates dopants for semiconductors for developing visible light-driven photocatalytic activity. Of particular relevance, the low luminescence efficiency of Ln-based nanoparticles is one of the main factors that limits their further applications. Carbon, which is present on the surface of all TiO2 photocatalysts, can be responsible for luminescence quenching processes and, thus, decreasing the photocatalytic activity of TiO2. This article presents a systematic experimental and theoretical study of the effects of carbon on the photocatalytic performance of Ho3+-modified TiO2. Ho3+-TiO2 photocatalysts modified with various carbon contents (from 0.5 to 20 mol.%) were successfully prepared using a simple hydrothermal method. As-obtained samples were characterized by UV-Vis diffuse reflectance spectroscopy (DRS/UV-Vis), X-ray diffraction (XRD), X-ray photoelectron emission spectroscopy (XPS), N2 adsorption measurements, photoluminescent spectroscopy (PL), field-emission scanning electron microscopy (FE-SEM) and scanning transmission microscopy (STEM). The photodegradation efficiency of phenol was estimated for visible light (λ > 420 nm and λ > 455 nm). The XPS and XRD analyses and theoretical calculations revealed that the substitutional doping of holmium and carbon in the TiO2 anatase structure resulted in the appearance of a new sub-band-gap. Changes in the material texture, BET surface area and pore volume can be easily controlled via carbon content in samples. Doping of the Ho3+-TiO2 photocatalysts with carbon resulted in quenching of the emission of Ho3+ and, thus, the photodegradation of phenol, was observed in samples containing smaller amounts of carbon. Sixty minutes of irradiation resulted in 89% of phenol degradation under visible light (λ > 420 nm).
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Affiliation(s)
- Patrycja Parnicka
- Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland
| | - Tomasz Grzyb
- Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University in Poznan, 60-780 Poznan, Poland
| | - Alicja Mikolajczyk
- Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland; Laboratory of Environmental Chemometrics, Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland
| | - Kunlei Wang
- Institute for Catalysis, Hokkaido University, Sapporo 001-0021, Japan
| | - Ewa Kowalska
- Institute for Catalysis, Hokkaido University, Sapporo 001-0021, Japan
| | - Norbert Steinfeldt
- Leibniz Institute for Catalysis, University of Rostock, 18059 Rostock, Germany
| | - Marek Klein
- Institute of Fluid-Flow Machinery, Polish Academy of Sciences, 80-231 Gdansk, Poland
| | - Paweł Mazierski
- Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland
| | - Adriana Zaleska-Medynska
- Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland
| | - Joanna Nadolna
- Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland.
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8
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Shvydkiv O, Jähnisch K, Steinfeldt N, Yavorskyy A, Oelgemöller M. Visible-light photooxygenation of α-terpinene in a falling film microreactor. Catal Today 2018. [DOI: 10.1016/j.cattod.2017.11.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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9
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Alex H, Loos P, Baramov T, Barry J, Godiawala T, Hassfeld J, Steinfeldt N. Polymer Encapsulated Cobalt-Based Catalysts (Co EnCatTM
) for Selective Continuous Hydrogenation of 1-Iodo-4-nitrobenzene. ChemCatChem 2017. [DOI: 10.1002/cctc.201700391] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Hannes Alex
- Leibniz-Institut für Katalyse e.V.; Albert-Einstein-Str. 29a 18059 Rostock Germany
| | - Patrick Loos
- Leibniz-Institut für Katalyse e.V.; Albert-Einstein-Str. 29a 18059 Rostock Germany
- Bayer AG; Friedrich-Ebert-Str. 217-333 42117 Wuppertal Germany
- Present address: Mercachem B.V.; Kerkenbos 1013 6546 BB Nijmegen The Netherlands
| | - Todor Baramov
- Leibniz-Institut für Katalyse e.V.; Albert-Einstein-Str. 29a 18059 Rostock Germany
- Bayer AG; Friedrich-Ebert-Str. 217-333 42117 Wuppertal Germany
| | - John Barry
- Reaxa Limited, BioHub; Alderley Edge Cheshire SK10 4TG United Kingdom
| | - Tanmay Godiawala
- Reaxa Limited, BioHub; Alderley Edge Cheshire SK10 4TG United Kingdom
| | - Jorma Hassfeld
- Bayer AG; Friedrich-Ebert-Str. 217-333 42117 Wuppertal Germany
| | - Norbert Steinfeldt
- Leibniz-Institut für Katalyse e.V.; Albert-Einstein-Str. 29a 18059 Rostock Germany
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Loos P, Alex H, Hassfeld J, Lovis K, Platzek J, Steinfeldt N, Hübner S. Selective Hydrogenation of Halogenated Nitroaromatics to Haloanilines in Batch and Flow. Org Process Res Dev 2015. [DOI: 10.1021/acs.oprd.5b00170] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Patrick Loos
- Bayer
Pharma AG, Friedrich-Ebert-Str. 217-333, D-42117 Wuppertal, Germany
- Leibniz-Institut
für Katalyse e.V. (LIKAT), Albert-Einstein-Str.
29a, D-18059 Rostock, Germany
| | - Hannes Alex
- Leibniz-Institut
für Katalyse e.V. (LIKAT), Albert-Einstein-Str.
29a, D-18059 Rostock, Germany
| | - Jorma Hassfeld
- Bayer
Pharma AG, Friedrich-Ebert-Str. 217-333, D-42117 Wuppertal, Germany
| | - Kai Lovis
- Bayer
Pharma AG, Friedrich-Ebert-Str. 217-333, D-42117 Wuppertal, Germany
| | - Johannes Platzek
- Bayer
Pharma AG, Friedrich-Ebert-Str. 217-333, D-42117 Wuppertal, Germany
| | - Norbert Steinfeldt
- Leibniz-Institut
für Katalyse e.V. (LIKAT), Albert-Einstein-Str.
29a, D-18059 Rostock, Germany
| | - Sandra Hübner
- Leibniz-Institut
für Katalyse e.V. (LIKAT), Albert-Einstein-Str.
29a, D-18059 Rostock, Germany
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Siyo B, Schneider M, Pohl MM, Langer P, Steinfeldt N. Synthesis, Characterization, and Application of PVP-Pd NP in the Aerobic Oxidation of 5-Hydroxymethylfurfural (HMF). Catal Letters 2014. [DOI: 10.1007/s10562-013-1186-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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12
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Kondratenko EV, Amrute AP, Pohl MM, Steinfeldt N, Mondelli C, Pérez-Ramírez J. Superior activity of rutile-supported ruthenium nanoparticles for HCl oxidation. Catal Sci Technol 2013. [DOI: 10.1039/c3cy00372h] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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13
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Steinfeldt N. In situ monitoring of Pt nanoparticle formation in ethylene glycol solution by SAXS-influence of the NaOH to Pt ratio. Langmuir 2012; 28:13072-13079. [PMID: 22891651 DOI: 10.1021/la3026232] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The temporal evolution of Pt nanoparticle formation in ethylene glycol solution from H(2)PtCl(6)·6H(2)O at 90 °C for different molar ratios of NaOH to Pt (84, 6.5, and 2) in the presence or absence of poly(N-vinyl-2-pyrrolidone) (PVP) as protecting agent was followed in situ by small-angle X-ray scattering (SAXS). The SAXS profiles were analyzed regarding particle size and size distribution using the Guinier approximation and the indirect Fourier transform technique (IFT). The NaOH to Pt ratio has an influence on the integral nanoparticle formation rate as well as on the metal reduction rate and the ratio of nucleation to growth reactions. The fastest nanoparticle formation rate was observed for the NaOH/Pt ratio of 6.5. The obtained results indicate that the differences in the particle formation rate might be due to differences in the reduction rate of the formed Pt complexes. In alkaline reaction media (NaOH/Pt = 84 or 6.5), small nanoparticles with a relatively narrow size distribution were formed. Therefore, it is assumed that for these NaOH/Pt ratios the particle formation is dominated by nucleation reactions. Additionally, the in situ studies point out that nanoparticles prepared at the NaOH/Pt ratio of 84 do not grow further after attaining a certain particle size. For a NaOH to Pt ratio of 2, that means in acidic medium, particle formation should be dominated by growing processes and, therefore, larger particles are formed accompanied by a broader particle size distribution. The influence of PVP on the nanoparticle formation rate is relatively low. However, in acidic medium, the presence of PVP is necessary in order to protect the formed nanoparticles from irreversible aggregation reactions.
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Affiliation(s)
- Norbert Steinfeldt
- Leibniz-Institut für Katalyse an der Universität Rostock, Rostock, Germany.
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14
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Berger-Karin C, Sebek M, Pohl MM, Bentrup U, Kondratenko VA, Steinfeldt N, Kondratenko EV. Tailored Noble Metal Nanoparticles on γ-Al2O3for High Temperature CH4Conversion to Syngas. ChemCatChem 2012. [DOI: 10.1002/cctc.201200096] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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15
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Steinfeldt N, Bentrup U, Jähnisch K. Reaction Mechanism and in Situ ATR Spectroscopic Studies of the 1-Decene Ozonolysis in Micro- and Semibatch Reactors. Ind Eng Chem Res 2009. [DOI: 10.1021/ie900726s] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Norbert Steinfeldt
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert Einstein-Strasse 29a, D-18059 Rostock, Germany
| | - Ursula Bentrup
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert Einstein-Strasse 29a, D-18059 Rostock, Germany
| | - Klaus Jähnisch
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert Einstein-Strasse 29a, D-18059 Rostock, Germany
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16
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Steinfeldt N, Abdallah R, Dingerdissen U, Jähnisch K. Ozonolysis of Acetic Acid 1-Vinyl-hexyl Ester in a Falling Film Microreactor. Org Process Res Dev 2007. [DOI: 10.1021/op7000673] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Norbert Steinfeldt
- Leibniz-Institut für Katalyse e. V. an der Universität Rostock, Aussenstelle Berlin, Richard-Willstätter-Str. 12, Berlin D-12489, Germany
| | - Radwan Abdallah
- Leibniz-Institut für Katalyse e. V. an der Universität Rostock, Aussenstelle Berlin, Richard-Willstätter-Str. 12, Berlin D-12489, Germany
| | - Uwe Dingerdissen
- Leibniz-Institut für Katalyse e. V. an der Universität Rostock, Aussenstelle Berlin, Richard-Willstätter-Str. 12, Berlin D-12489, Germany
| | - Klaus Jähnisch
- Leibniz-Institut für Katalyse e. V. an der Universität Rostock, Aussenstelle Berlin, Richard-Willstätter-Str. 12, Berlin D-12489, Germany
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17
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Kondratenko EV, Steinfeldt N, Baerns M. Transient and steady state investigation of selective and non-selective reaction pathways in the oxidative dehydrogenation of propane over supported vanadia catalysts. Phys Chem Chem Phys 2006; 8:1624-33. [PMID: 16633647 DOI: 10.1039/b515603n] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mechanistic aspects of the formation of C3H6, CO and CO2 in the oxidative dehydrogenation of propane over VOx/gamma-Al2O3 materials have been investigated by means of steady state and transient isotopic tests. The materials possessed highly dispersed and polymerised VOx species as well as bulk-like V2O5. Propene was primarily formed via oxidative dehydrogenation of propane by lattice oxygen of VOx species. It was suggested that non-selective consecutive propene oxidation is initiated by the breaking of the C-C bond in the molecule by the lattice oxygen, forming formaldehyde as a side product, which is further oxidised to CO and CO2. The following order of initial steady state propene selectivity (at a zero degree of propane conversion) as a function of the nature of VOx species was established: a mixture of bulk-like V2O5 and polymerised VOx>polymerised VOx>highly dispersed VOx species. The low propene selectivity over highly dispersed VOx species was explained by the fact that these species do not fully cover the bare acidic surface of gamma-Al2O3 where propene adsorption and further oxidation take place. Thus, two different locations of COx formation were considered: (i) in the vicinity of acidic sites of the support and (ii) on VOx species. The propene selectivity over samples possessing polymerised VOx species and bulk-like V2O5 strongly decreased with an increasing degree of propane conversion. Contrarily, highly dispersed VOx species showed the lowest ability for consecutive propene oxidation.
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Affiliation(s)
- Evgenii V Kondratenko
- Leibniz-Institut für Katalyse e. V. an der Universität Rostock, Aussenstelle Berlin, Richard-Willstätter-Str. 12, D-12489, Berlin, Germany.
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Steinfeldt N, Dingerdissen U, Baerns M. Application of a Multichannel Microstructured Reactor for Studies of Oxidative Propane Dehydrogenation. Chem Eng Technol 2005. [DOI: 10.1002/ceat.200407171] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Steinfeldt N, Linke D, Jähnisch K, Baerns M. Anwendung eines mikrostrukturierten Mehrkanalreaktors für kinetische Untersuchungen der oxidativen Dehydrierung von Propan. CHEM-ING-TECH 2004. [DOI: 10.1002/cite.200403394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Steinfeldt N, Dropka N, Wolf D, Baerns M. Application of Multichannel Microreactors for Studying Heterogeneous Catalysed Gas Phase Reactions. Chem Eng Res Des 2003. [DOI: 10.1205/026387603322302904] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Wassermann K, Palm R, Lunk HJ, Fuchs J, Steinfeldt N, Stoesser R. Condensation of Keggin Anions Containing Chromium(III) and Aluminum(III), Respectively. 1. Synthesis and X-ray Structural Determination of [{A-.alpha.-SiO4W9O30(OH)3Cr3}2(OH)3]11-. Inorg Chem 2002. [DOI: 10.1021/ic00124a018] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wassermann K, Lunk HJ, Palm R, Fuchs J, Steinfeldt N, Stösser R, Pope MT. Polyoxoanions Derived from [gamma-SiO(4)W(10)O(32)](8-)-Containing Oxo-Centered Dinuclear Chromium(III) Carboxylato Complexes: Synthesis and Single-Crystal Structural Determination of [gamma-SiO(4)W(10)O(32)(OH)Cr(2)(OOCCH(3))(2)(OH(2))(2)](5-). Inorg Chem 1996; 35:3273-3279. [PMID: 11666528 DOI: 10.1021/ic9513954] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The previously unknown heteropolyoxometalates [gamma-SiO(4)W(10)O(32)(OH)Cr(2)(OOCR)(2)(OH(2))(2)](5-) (R = H, CH(3)) have been prepared by the reaction of [gamma-SiO(4)W(10)O(32)](8-) with [Cr(OH(2))(6)](3+) in formate or acetate buffer solution. Isolation of these new Cr(III)-substituted polyoxometalates was accomplished both as Cs(+) salts and as the Bu(4)N(+) salt for the acetate-containing anion. The compounds were characterized by elemental analysis, UV/vis, IR, and ESR spectroscopy, and cyclic voltammetry. The single-crystal X-ray structural analysis of (Bu(4)N)(3)H(2)[gamma-SiO(4)W(10)O(32)(OH)Cr(2)(OOCCH(3))(2)(OH(2))(2)].3H(2)O [P2(1)2(1)2(1); a = 17.608(12), b = 20.992(13), c = 24.464(11) Å; Z = 4; R = 0.057 for 6549 observed independent reflections] reveals that the two corner-linked CrO(6) octahedra are additionally bridged by two acetate groups, demonstrating the relationship to the well-studied oxo-centered trinuclear carboxylato complexes of Cr(III).
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Affiliation(s)
- Knut Wassermann
- Institut für Chemie der Humboldt-Universität zu Berlin, Hessische Strasse 1/2, 10115 Berlin, Germany, Fachbereich Chemie der Freien Universität, Fabeckstrasse 34-36, 14195 Berlin, Germany, and Department of Chemistry, Georgetown University, Washington, D.C. 20057
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Brückner A, Martin A, Steinfeldt N, Wolf GU, Lücke B. Investigation of vanadium phosphorus oxide catalysts (VPO) during toluene ammoxidation: new mechanistic insights by in situ EPR. ACTA ACUST UNITED AC 1996. [DOI: 10.1039/ft9969204257] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Br�ckner A, L�ck R, Calov U, Steinfeldt N. Thermisch induzierte Bewegungsvorg�nge in kristallinen Guanidiniumhexafluorometallaten, (C(NH2)3)3MF6 (M = Al, Ga, In) ? eine in situ ESR-Untersuchung. Z Anorg Allg Chem 1992. [DOI: 10.1002/zaac.19926170127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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