Commemorative Issue in Honor of Professor Gerhard Ertl on the Occasion of His 85th Birthday

A special issue of Catalysts (ISSN 2073-4344). This special issue belongs to the section "Environmental Catalysis".

Deadline for manuscript submissions: closed (10 October 2021) | Viewed by 40772

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Department of Nanomaterials in Natural Sciences, Institute for Nanomaterials, Advanced Technology and Innovation, Technical University of Liberec, Studentska 1402/2, Liberec, Czech Republic
Interests: environmental chemistry; sustainable chemistry; water and wastewater treatmentł advanced oxidation processes
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Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering (ChEE), University of Cincinnati, Cincinnati, OH, USA
Interests: advanced oxidation; nanotechnology; water treatment; water quality; environmental sensors; environmental catalysis
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Faculty of Chemistry, University of Warsaw, 1 Pasteur St., 02-093 Warsaw, Poland
Interests: synthesis of new nanomaterials for Raman spectroscopy analysis of surfaces; photochemical synthesis and reconstruction of silver nanostructures including their so-called plasmon-driven transformation; application of surface enhanced Raman spectroscopy for DNA detection
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Co-Guest Editor
South Carolina Center of Economic Excellence for Strategic Approaches to the Generation of Electricity (SAGE), Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208, USA
Interests: high-throughput catalysis; fabrication of conducting polymer nanofilms; non-linear dynamics of heterogeneously catalyzed reactions; time-resolved IR spectroscopy of supported catalysts

Special Issue Information

Dear Colleagues,

Our journal is pleased to publish a Special Issue in honor of Professor Gerhard Ertl for his 85th birthday. Prof. Ertl (born 10 October 1936) is a German physicist and a Professor emeritus at the Department of Physical Chemistry, Fritz-Haber-Institut der Max-Planck-Gesellschaft in Berlin, Germany. He was awarded the 2007 Nobel Prize in Chemistry for his study of chemical processes on solid surfaces. The Royal Swedish Academy of Sciences said that Prof. Ertl’s research laid the foundation of modern surface chemistry, which has helped to explain how fuel cells produce energy without pollution, how catalytic converters clean up car exhausts, etc. Moreover, his research has helped to explain why the ozone layer is thinning.

In honor and recognition of Professor Gerhard Ertl’s outstanding career contributions to the field of heterogeneous catalysis, this Special Issue of Catalysts welcomes the submission of original research manuscripts or reviews in this area. We plan to receive submissions from now to 10 October 2021. Manuscripts will be published online on an ongoing basis after being processed.

“This Special Issue is dedicated to honor Professor Gerhard Ertl for his 85th birthday, a key figure in the topic of heterogeneous catalysis.” Authors are invited to add this sentence in the acknowledgement of their contributions.

Dr. Stanisław Wacławek
Prof. Dr. Dionysios (Dion) D. Dionysiou
Dr. Andrzej Kudelski
Guest Editors

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Catalysts is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2200 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Selected Awards and Honors of Prof. Ertl:

  • Member of the German Academy of Natural Scientists (Deutschen Akademie der Naturforscher) Leopoldina (since 1986), the Berlin-Brandenburg Academy of Sciences (Berlin-Brandenburgischen Akademie der Wissenschaften) and the Academia Europaea;
  • Corresponding member of the Brunswick Scientific Society (Braunschweigischen Wissenschaftlichen Gesellschaft), the Austrian Academy of Sciences (AAS), the Bavarian Academy of Sciences (BAdW) and the North Rhine-Westphalian Academy of Sciences and Arts;
  • Honorary professorships at three Universities in Berlin;
  • Several honorary doctorates: including from the Ruhr-University Bochum, Westphalia (1992); from the University of Münster (2000) and by the Belgian Katholieke Universiteit Leuven (2003), the Swedish Chalmers University and the Danish Aarhus Universitet;
  • Carl-Friedrich-Gauss Medal of Brunswick Scientific Society (1985);
  • Liebig Medal of the German Chemical Society (1987);
  • First Alwin Mittasch Medal (1990);
  • Bunsen Medal of the German Bunsen Society for Physical Chemistry (1992);
  • Honorary Member of the German Bunsen Society for Physical Chemistry (2006);
  • Japan Prize (1992) and the Great Cross of Merit of the Federal Republic of Germany (1992);
  • Honorary Member of the Royal Society of Edinburgh (RSE; 1993);
  • Honorary Member of the American Academy of Arts and Sciences (1993);
  • Foreign Associate of the National Academy of Sciences (USA; 2002);
  • Nobel Prize in Chemistry for his "studies of chemical processes on solid surfaces" (October 10, 2007);
  • Awarded the Otto Hahn Prize (November 27, 2007);
  • The Great Cross of Merit with Star of the Order of Merit of the Federal Republic of Germany (April 8, 2008);
  • Order of Merit of the State of Baden-Wuerttemberg from the Prime Minister Günther Oettinger (April 26, 2008);
  • Honorary membership of the DECHEMA Society for Chemical Engineering and Biotechnology (September 8, 2008);
  • The comprehensive school Sprendlingen (district Mainz-Bingen) received the name IGS Gerhard Ertl (September 27, 2008);
  • A chemistry building of the LMU Munich was named to Gerhard Ertl (December 16, 2008);
  • Honorary Member of the Physical Society (October 29, 2008);
  • Honorary membership at the TU Berlin (December 4, 2009);
  • Foreign Member of the Polish Academy of Sciences (2009);
  • The "Gerhard Ertl Center" was opened on the campus of TU Berlin Charlottenburg. It is the main building of the Berlin Cluster of Excellence "Unifying Concepts in Catalysis" (October 2012);
  • Honorary Member of the German Physical Society (2012).

Keywords

  • heterogeneous catalysis
  • fuel cells
  • Haber–Bosch process
  • environmental catalysis
  • surface chemistry

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Published Papers (11 papers)

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Editorial

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2 pages, 178 KiB  
Editorial
Commemorative Issue in Honor of Professor Gerhard Ertl on the Occasion of His 85th Birthday
by Stanisław Wacławek, Andrzej Kudelski, Jochen A. Lauterbach and Dionysios D. Dionysiou
Catalysts 2022, 12(6), 624; https://doi.org/10.3390/catal12060624 - 6 Jun 2022
Cited by 1 | Viewed by 1483
Abstract
This Special Issue (SI) is dedicated to Professor Gerhard Ertl on his eighty-fifth birthday [...] Full article

Research

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12 pages, 16342 KiB  
Article
Anomaly Negative Resistance Phenomena in Highly Epitaxial PrBa0.7Ca0.3Co2O5+δ Thin Films Induced from Superfast Redox Reactions
by Yumei Luo, Xing Xu, Yudong Xia, Shengli Pang, Fen Xu, Myung-Hwan Whangbo, Lixian Sun and Chonglin Chen
Catalysts 2021, 11(12), 1441; https://doi.org/10.3390/catal11121441 - 26 Nov 2021
Cited by 2 | Viewed by 1746
Abstract
Thin films of Ca-doped double perovskite, PrBa0.7Ca0.3Co2O5+δ (PBCC), were epitaxially grown on (001) SrTiO3, and their redox reactions under a switching flow of H2 and O2 gases were examined at various temperatures [...] Read more.
Thin films of Ca-doped double perovskite, PrBa0.7Ca0.3Co2O5+δ (PBCC), were epitaxially grown on (001) SrTiO3, and their redox reactions under a switching flow of H2 and O2 gases were examined at various temperatures by measuring the resistance R(t) of the films as a function of the gas flow time t. In the temperature range between 350 and 725 °C, these thin films are reduced and oxidized in an ultrafast manner under the flow of H2 and O2 gases, respectively, suggesting that PBCC thin films are promising candidates for developing ultra-sensitive oxygen sensors or SOFC cathodes at intermediate or high temperatures. When the gas flow is switched to O2, the reduced PBCC thin films exhibit a negative resistance at temperatures above 600 °C but a positive resistance at temperatures below 600 °C. The probable cause for these anomalous transport properties is the diffusion of the H atoms from the cathode to the anode in the PBCC film, which provides a current opposite to that resulting from the external voltage. Full article
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15 pages, 2546 KiB  
Article
Boosting the H2 Production Efficiency via Photocatalytic Organic Reforming: The Role of Additional Hole Scavenging System
by Yamen AlSalka, Osama Al-Madanat, Amer Hakki and Detlef W. Bahnemann
Catalysts 2021, 11(12), 1423; https://doi.org/10.3390/catal11121423 - 23 Nov 2021
Cited by 20 | Viewed by 2564
Abstract
The simultaneous photocatalytic H2 evolution with environmental remediation over semiconducting metal oxides is a fascinating process for sustainable fuel production. However, most of the previously reported photocatalytic reforming showed nonstoichiometric amounts of the evolved H2 when organic substrates were used. To [...] Read more.
The simultaneous photocatalytic H2 evolution with environmental remediation over semiconducting metal oxides is a fascinating process for sustainable fuel production. However, most of the previously reported photocatalytic reforming showed nonstoichiometric amounts of the evolved H2 when organic substrates were used. To explain the reasons for this phenomenon, a careful analysis of the products and intermediates in gas and aqueous phases upon the photocatalytic hydrogen evolution from oxalic acid using Pt/TiO2 was performed. A quadrupole mass spectrometer (QMS) was used for the continuous flow monitoring of the evolved gases, while high performance ion chromatography (HPIC), isotopic labeling, and electron paramagnetic resonance (EPR) were employed to understand the reactions in the solution. The entire consumption of oxalic acid led to a ~30% lower H2 amount than theoretically expected. Due to the contribution of the photo-Kolbe reaction mechanism, a tiny amount of formic acid was produced then disappeared shortly after the complete consumption of oxalic acid. Nevertheless, a much lower concentration of formic acid was generated compared to the nonstoichiometric difference between the formed H2 and the consumed oxalic acid. Isotopic labeling measurements showed that the evolved H2, HD, and/or D2 matched those of the solvent; however, using D2O decreased the reaction rate. Interestingly, the presence of KI as an additional hole scavenger with oxalic acid had a considerable impact on the reaction mechanism, and thus the hydrogen yield, as indicated by the QMS and the EPR measurements. The added KI promoted H2 evolution to reach the theoretically predictable amount and inhibited the formation of intermediates without affecting the oxalic acid degradation rate. The proposed mechanism, by which KI boosts the photocatalytic performance, is of great importance in enhancing the overall energy efficiency for hydrogen production via photocatalytic organic reforming. Full article
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15 pages, 1695 KiB  
Article
Crystal Imperfections of Industrial Vanadium Phosphorous Oxide Catalysts
by Isabella Kappel, Sebastian Böcklein, SoHyun Park, Michael Wharmby, Gerhard Mestl and Wolfgang W. Schmahl
Catalysts 2021, 11(11), 1325; https://doi.org/10.3390/catal11111325 - 31 Oct 2021
Cited by 2 | Viewed by 1973
Abstract
This study presents information about crystal imperfections in the main phase of industrial vanadium phosphorous oxide catalysts that are used to catalyze the oxidation of n-butane to maleic anhydride, being an important intermediate in the chemical industry. The mechanism of this reaction [...] Read more.
This study presents information about crystal imperfections in the main phase of industrial vanadium phosphorous oxide catalysts that are used to catalyze the oxidation of n-butane to maleic anhydride, being an important intermediate in the chemical industry. The mechanism of this reaction is still debated, and the catalytically active and selective surface centers have not yet been identified. The results presented are based on X-ray diffraction data obtained by both laboratory-scale and synchrotron powder diffraction experiments, as well as laboratory-scale single-crystal diffraction experiments. It has been proven that pronounced Bragg reflection broadening effects found in laboratory-scale powder diffraction patterns of industrial VPO catalysts are real and not due to an insufficient 2-θ resolution of the apparatus. In the framework of this work, a powder diffraction full profile fitting strategy was developed using the TOPAS software, which was applied to analyze the X-ray diffraction data of four differently activated industrial catalyst samples, originating from one batch after they had been catalytically tested. It was found that the reflection broadening is mainly caused by an anisotropic crystal size, which results in platelet-shaped crystallites of vanadyl pyrophosphate. A further contribution to the reflex broadening, especially for (111), was found to be a result of stacking faults perpendicular to the a direction in the crystal structure of vanadyl pyrophosphate. These results were used to elaborate on possible correlations between structural proxies and catalytic performance. A direct correlation between the extension of coherently scattering domains in the z direction and the catalyst’s selectivity could be proven, whereas the activity turned out to be dependent on the crystallite shape. Regarding the phase contents, it could be shown that sample catalysts containing a higher amount of β-VO(PO3)2 showed increased catalytic activity. Full article
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15 pages, 5541 KiB  
Article
What Is the Real State of Single-Atom Catalysts under Electrochemical Conditions—From Adsorption to Surface Pourbaix Plots?
by Ana S. Dobrota, Tanja Đokić, Natalia V. Skorodumova, Slavko V. Mentus and Igor A. Pašti
Catalysts 2021, 11(10), 1207; https://doi.org/10.3390/catal11101207 - 8 Oct 2021
Cited by 5 | Viewed by 2977
Abstract
The interest in single-atom catalysts (SACs) is increasing, as these materials have the ultimate level of catalyst utilization, while novel reactions where SACs are used are constantly being discovered. However, to properly understand SACs and to further improve these materials, it is necessary [...] Read more.
The interest in single-atom catalysts (SACs) is increasing, as these materials have the ultimate level of catalyst utilization, while novel reactions where SACs are used are constantly being discovered. However, to properly understand SACs and to further improve these materials, it is necessary to consider the nature of active sites under operating conditions. This is particularly important when SACs are used as electrocatalysts due to harsh experimental conditions, including extreme pH values or high anodic and cathodic potential. In this contribution, density functional theory-based thermodynamic modelling is used to address the nature of metal centers in SACs formed by embedding single metal atoms (Ru, Rh, Ir, Ni, Pd, Pt, Cu, Ag, and Au) into graphene monovacancy. Our results suggest that none of these SAC metal centers are clean at any potential or pH in the water thermodynamic stability region. Instead, metal centers are covered with Hads, OHads, or Oads, and in some cases, we observed the restructuring of the metal sites due to oxygen incorporation. Based on these findings, it is suggested that setting up theoretical models for SAC modelling and the interpretation of ex situ characterization results using ultra-high vacuum (UHV) techniques requires special care, as the nature of SAC active sites under operating conditions can significantly diverge from the basic models or the pictures set by the UHV measurements. Full article
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22 pages, 4542 KiB  
Article
Phosphate Enrichment of Niobium-Based Catalytic Surfaces in Relation to Reactions of Carbohydrate Biomass Conversion: The Case Studies of Inulin Hydrolysis and Fructose Dehydration
by Mariana N. Catrinck, Sebastiano Campisi, Paolo Carniti, Reinaldo F. Teófilo, Filippo Bossola and Antonella Gervasini
Catalysts 2021, 11(9), 1077; https://doi.org/10.3390/catal11091077 - 7 Sep 2021
Cited by 14 | Viewed by 2704
Abstract
In this work, some physical mixtures of Nb2O5·nH2O and NbOPO4 were prepared to study the role of phosphate groups in the total acidity of samples and in two reactions involving carbohydrate biomass: hydrolysis of polyfructane and [...] Read more.
In this work, some physical mixtures of Nb2O5·nH2O and NbOPO4 were prepared to study the role of phosphate groups in the total acidity of samples and in two reactions involving carbohydrate biomass: hydrolysis of polyfructane and dehydration of fructose/glucose to 5-hydroxymethylfurfural (HMF). The acid and catalytic properties of the mixtures were dominated by the phosphate group enrichment. Lewis and Brønsted acid sites were detected by FT-IR experiments with pyridine adsorption/desorption under dry and wet conditions. Lewis acidity decreased with NbP in the composition, while total acidity of the samples, measured by titrations with phenylethylamine in cyclohexane (~3.5 μeq m−2) and water (~2.7 μeq m−2), maintained almost the same values. Inulin conversion took advantage of the presence of surfaces rich in Brønsted sites, and NbOPO4 showed the best hydrolysis activity with glucose/fructose formation. The catalyst with a more phosphated surface showed less deactivation during the dehydration of fructose/glucose into HMF. Full article
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22 pages, 5284 KiB  
Article
Extracting Turnover Frequencies of Electron Transfer in Heterogeneous Catalysis: A Study of IrO2-TiO2 Anatase for Water Oxidation Using Ce4+ Cations
by Mogbel Alrushaid, Muhammad A. Nadeem, Khaja A. Wahab and Hicham Idriss
Catalysts 2021, 11(9), 1030; https://doi.org/10.3390/catal11091030 - 26 Aug 2021
Cited by 7 | Viewed by 3404
Abstract
Within the context of electron transfer during the catalytic water oxidation reaction, the Ir-based system is among the most active. The reaction, mimicking photosynthesis II, requires the use of an electron acceptor such the Ce4+ cation. This complex reaction, involving adsorbed water [...] Read more.
Within the context of electron transfer during the catalytic water oxidation reaction, the Ir-based system is among the most active. The reaction, mimicking photosynthesis II, requires the use of an electron acceptor such the Ce4+ cation. This complex reaction, involving adsorbed water at the interface of the metal cation and Ce4+, has mostly been studied in homogenous systems. To address the ambiguity regarding the gradual transformation of a homogenous system into a heterogeneous one, we prepared and studied a heterogeneous catalyst system composed of IrO2, with a mean particle size ranging from about 5 Å to 10 Å, dispersed on a TiO2 anatase support, with the objective of probing into the different parameters of the reaction, as well as the compositional changes and rates. The system was stable for many of the runs that were conducted (five consecutive runs with 0.18 M of Ce4+ showed the same reaction rate with TON > 56,000) and, equally importantly, was stable without induction periods. Extraction of the reaction rates from the set of catalysts, with an attempt to normalize them with respect to Ir loading and, therefore, to obtain turnover frequencies (TOF), was conducted. While, within reasonable deviations, the TOF numbers extracted from TPR and XPS Ir4f were close, those extracted from the particle shape (HR-STEM) were considerably larger. The difference indicates that bulk Ir atoms contribute to the electron transfer reaction, which may indicate that the reaction rate is dominated by the reorganization energy between the redox couples involved. Therefore, the normalization of reaction rates with surface atoms may lead to an overestimation of the site activity. Full article
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17 pages, 2762 KiB  
Article
Kinetics Study of the Hydrodeoxygenation of Xylitol over a ReOx-Pd/CeO2 Catalyst
by Blake MacQueen, Michael Royko, Bradie S. Crandall, Andreas Heyden, Yomaira J. Pagán-Torres and Jochen Lauterbach
Catalysts 2021, 11(1), 108; https://doi.org/10.3390/catal11010108 - 14 Jan 2021
Cited by 12 | Viewed by 3125
Abstract
In this study, we elucidate the reaction kinetics for the simultaneous hydrodeoxygenation of xylitol to 1,2-dideoxypentitol and 1,2,5-pentanetriol over a ReOx-Pd/CeO2 (2.0 weight% Re, 0.30 weight% Pd) catalyst. The reaction was determined to be a zero-order reaction with respect to [...] Read more.
In this study, we elucidate the reaction kinetics for the simultaneous hydrodeoxygenation of xylitol to 1,2-dideoxypentitol and 1,2,5-pentanetriol over a ReOx-Pd/CeO2 (2.0 weight% Re, 0.30 weight% Pd) catalyst. The reaction was determined to be a zero-order reaction with respect to xylitol. The activation energy was elucidated through an Arrhenius relationship as well as non-Arrhenius kinetics. The Arrhenius relationship was investigated at 150–170 °C and a constant H2 pressure of 10 bar resulting in an activation energy of 48.7 ± 10.5 kJ/mol. The investigation of non-Arrhenius kinetics was conducted at 120–170 °C and a sub-Arrhenius relation was elucidated with activation energy being dependent on temperature, and ranging from 10.2–51.8 kJ/mol in the temperature range investigated. Internal and external mass transfer were investigated through evaluating the Weisz–Prater criterion and the effect of varying stirring rate on the reaction rate, respectively. There were no internal or external mass transfer limitations present in the reaction. Full article
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20 pages, 5073 KiB  
Article
Comparison of Catalytic Properties of Vanadium Centers Introduced into BEA Zeolite and Present on (010) V2O5 Surface–DFT Studies
by Agnieszka Drzewiecka-Matuszek, Renata Tokarz-Sobieraj, Małgorzata Witko and Dorota Rutkowska-Zbik
Catalysts 2020, 10(9), 1080; https://doi.org/10.3390/catal10091080 - 18 Sep 2020
Cited by 5 | Viewed by 3269
Abstract
Vanadium-based catalysts, in which vanadium is present either as bulk V2O5 or as isolated species, are active in numerous oxidation reactions. In the present study, vanadium speciation and the possibility of its introduction in various forms (V=O, V–OH, V(=O)(–OH)) into [...] Read more.
Vanadium-based catalysts, in which vanadium is present either as bulk V2O5 or as isolated species, are active in numerous oxidation reactions. In the present study, vanadium speciation and the possibility of its introduction in various forms (V=O, V–OH, V(=O)(–OH)) into the structurally different crystallographic positions in BEA zeolite was considered by means of Density Functional Theory (DFT). Out of nine nonequivalent positions, T2 and T3 positions are the most preferred. The former may accommodate V=O or V–OH, the latter V–OH or V(=O)(–OH). The structural and electronic properties of all possible centers present in the BEA zeolite are then compared with the characteristics of the same species on the most abundant (010) V2O5 surface. It is demonstrated that they exhibit higher nucleophilic character when introduced into the zeolite, and thus, may be more relevant for catalysis. Full article
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Review

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26 pages, 2460 KiB  
Review
Propylene Synthesis: Recent Advances in the Use of Pt-Based Catalysts for Propane Dehydrogenation Reaction
by Marco Martino, Eugenio Meloni, Giovanni Festa and Vincenzo Palma
Catalysts 2021, 11(9), 1070; https://doi.org/10.3390/catal11091070 - 3 Sep 2021
Cited by 28 | Viewed by 10347
Abstract
Propylene is one of the most important feedstocks in the chemical industry, as it is used in the production of widely diffused materials such as polypropylene. Conventionally, propylene is obtained by cracking petroleum-derived naphtha and is a by-product of ethylene production. To ensure [...] Read more.
Propylene is one of the most important feedstocks in the chemical industry, as it is used in the production of widely diffused materials such as polypropylene. Conventionally, propylene is obtained by cracking petroleum-derived naphtha and is a by-product of ethylene production. To ensure adequate propylene production, an alternative is needed, and propane dehydrogenation is considered the most interesting process. In literature, the catalysts that have shown the best performance in the dehydrogenation reaction are Cr-based and Pt-based. Chromium has the non-negligible disadvantage of toxicity; on the other hand, platinum shows several advantages, such as a higher reaction rate and stability. This review article summarizes the latest published results on the use of platinum-based catalysts for the propane dehydrogenation reaction. The manuscript is based on relevant articles from the past three years and mainly focuses on how both promoters and supports may affect the catalytic activity. The published results clearly show the crucial importance of the choice of the support, as not only the use of promoters but also the use of supports with tuned acid/base properties and particular shape can suppress the formation of coke and prevent the deep dehydrogenation of propylene. Full article
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25 pages, 2924 KiB  
Review
Facet-Dependent Reactivity of Ceria Nanoparticles Exemplified by CeO2-Based Transition Metal Catalysts: A Critical Review
by Michalis Konsolakis and Maria Lykaki
Catalysts 2021, 11(4), 452; https://doi.org/10.3390/catal11040452 - 31 Mar 2021
Cited by 42 | Viewed by 5360
Abstract
The rational design and fabrication of highly-active and cost-efficient catalytic materials constitutes the main research pillar in catalysis field. In this context, the fine-tuning of size and shape at the nanometer scale can exert an intense impact not only on the inherent reactivity [...] Read more.
The rational design and fabrication of highly-active and cost-efficient catalytic materials constitutes the main research pillar in catalysis field. In this context, the fine-tuning of size and shape at the nanometer scale can exert an intense impact not only on the inherent reactivity of catalyst’s counterparts but also on their interfacial interactions; it can also opening up new horizons for the development of highly active and robust materials. The present critical review, focusing mainly on our recent advances on the topic, aims to highlight the pivotal role of shape engineering in catalysis, exemplified by noble metal-free, CeO2-based transition metal catalysts (TMs/CeO2). The underlying mechanism of facet-dependent reactivity is initially discussed. The main implications of ceria nanoparticles’ shape engineering (rods, cubes, and polyhedra) in catalysis are next discussed, on the ground of some of the most pertinent heterogeneous reactions, such as CO2 hydrogenation, CO oxidation, and N2O decomposition. It is clearly revealed that shape functionalization can remarkably affect the intrinsic features and in turn the reactivity of ceria nanoparticles. More importantly, by combining ceria nanoparticles (CeO2 NPs) of specific architecture with various transition metals (e.g., Cu, Fe, Co, and Ni) remarkably active multifunctional composites can be obtained due mainly to the synergistic metalceria interactions. From the practical point of view, novel catalyst formulations with similar or even superior reactivity to that of noble metals can be obtained by co-adjusting the shape and composition of mixed oxides, such as Cu/ceria nanorods for CO oxidation and Ni/ceria nanorods for CO2 hydrogenation. The conclusions derived could provide the design principles of earth-abundant metal oxide catalysts for various real-life environmental and energy applications. Full article
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