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Catalysis by Precious Metals, Past and Future
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Catalysis by Precious Metals, Past and Future

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

Deadline for manuscript submissions: closed (31 July 2019) | Viewed by 60028

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editors

Dr. Marcela Martinez Tejada

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Guest Editor
Departamento de Química Inorgánica - Instituto de Ciencia de Materiales de Sevilla, Universidad de Sevilla - CSIC, Av. Américo Vespucio 49, 41092 Sevilla, Spain
Interests: heterogeneous catalysis; catalysis by noble metals; catalysis by transition metals; structured reactors; H2 production and clean-up; steam reforming; water–gas shift reaction; CO oxidation; CO preferential oxidation; CO and CO2 methanation; CO2 capture; carbon-based catalysts
Special Issues, Collections and Topics in MDPI journals
Prof. Dr. Svetlana Ivanova

E-Mail Website
Guest Editor
Department of Inorganic Chemistry, Institute of Materials Science of Sevilla, University of Seville, 41092 Seville, Spain
Interests: Design and application of heterogeneous catalysts, CO and hydrocarbons oxidation, H2 clean-up processes, biorefinery, CO2 capture and utilization, biomass chemical valorization
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

“Shiny, malleable, and resistant to corrosion”—that is the first obvious definition of precious metals, to which expensive and scarce can be added. Their use in jewellery, trade, and arts has led to a new era in which metal catalytic potential has been discovered, and, nowadays, precious metals are key players in the chemical industry. Platinum, alone or in combination with rhodium, was the first precious metal to participate catalytically in the sulfuric and nitric acid production processes. Gold, in return, has entered the group of catalytically active metals in the last few decades. The use of all those metals, in their bulk form, was successively limited due to their high cost and the highly dispersed and supported metal nanoparticles that appeared on the scene. The use of supports improves the dispersion of the precious metals, thus reducing their quantity and decreasing the cost of the final catalyst and also preventing metal sintering, loss of catalytically active sites, and deactivation. Both support and precious metals cooperate in the formation of an efficient catalytic machine. The precious metal-support interaction depends on many factors, like precious metal contents, the nature of support and metal, employed preparation methods, and also metal nanoparticles morphology. The addition of small amounts of noble metals into the formulation of other transition metals catalysts and the use of bimetallic noble metal catalysts are also quite attractive, since they can enhance the precious metal-support interaction. Thus, the diversity of supported precious metal catalysts is reflected in their versatility and enlarges their current and future horizons.

This Special Issue will reveal the importance of precious metals catalysis and will be focused on mono- and bi-metallic formulations, on any supported catalysts, and on the promoted catalytic effect of others transition metals catalysts using the precious metal effect. The application of precious metals in diverse reactions of interest, either homogeneous or heterogeneous, and complete studies of the preparation, characterization, and structuring of the supported precious metal catalysts, are welcomed, as well as operando and/or kinetics studies of mechanisms and catalytic performance.

Prof. Marcela Martinez Tejada
Prof. Svetlana Ivanova
Guest Editors

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Keywords

  • heterogeneous catalysis
  • homogeneous catalysis
  • precious metals catalysis
  • monometallic catalysts
  • bimetallic catalysts
  • gold catalysts
  • palladium catalysts
  • platinum catalysts
  • ruthenium catalysts
  • rhodium catalysts
  • silver catalysts
  • iridium catalysts
  • microchannel reactors
  • kinetic studies
  • in situ and operando studies
  • catalysts characterization

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Published Papers (13 papers)

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Editorial

Jump to: Research, Review

3 pages, 365 KiB  
Editorial
Editorial: Special Issue Catalysis by Precious Metals, Past and Future
by Svetlana Ivanova and Marcela Martínez Tejada
Catalysts 2020, 10(2), 247; https://doi.org/10.3390/catal10020247 - 19 Feb 2020
Cited by 5 | Viewed by 3004
Abstract
Precious metal catalysis is often synonymous with diversity and versatility [...] Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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Research

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12 pages, 1962 KiB  
Article
Gas Phase Catalytic Hydrogenation of C4 Alkynols over Pd/Al2O3
by Alberto González-Fernández, Chiara Pischetola and Fernando Cárdenas-Lizana
Catalysts 2019, 9(11), 924; https://doi.org/10.3390/catal9110924 - 6 Nov 2019
Cited by 9 | Viewed by 3863
Abstract
Alkenols are commercially important chemicals employed in the pharmaceutical and agro-food industries. The conventional production route via liquid phase (batch) alkynol hydrogenation suffers from the requirement for separation/purification unit operations to extract the target product. We have examined, for the first time, the [...] Read more.
Alkenols are commercially important chemicals employed in the pharmaceutical and agro-food industries. The conventional production route via liquid phase (batch) alkynol hydrogenation suffers from the requirement for separation/purification unit operations to extract the target product. We have examined, for the first time, the continuous gas phase hydrogenation (P = 1 atm; T = 373 K) of primary (3-butyn-1-ol), secondary (3-butyn-2-ol) and tertiary (2-methyl-3-butyn-2-ol) C4 alkynols using a 1.2% wt. Pd/Al2O3 catalyst. Post-TPR, the catalyst exhibited a narrow distribution of Pdδ- (based on XPS) nanoparticles in the size range 1-6 nm (mean size = 3 nm from STEM). Hydrogenation of the primary and secondary alkynols was observed to occur in a stepwise fashion (-C≡C- → -C=C- → -C-C-) while alkanol formation via direct -C≡C- → -C-C- bond transformation was in evidence in the conversion of 2-methyl-3-butyn-2-ol. Ketone formation via double bond migration was promoted to a greater extent in the transformation of secondary (vs. primary) alkynol. Hydrogenation rate increased in the order primary < secondary < tertiary. The selectivity and reactivity trends are accounted for in terms of electronic effects. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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24 pages, 8809 KiB  
Article
Synthesis, Structure, and Catalytic Reactivity of Pd(II) Complexes of Proline and Proline Homologs
by David B. Hobart, Jr., Joseph S. Merola, Hannah M. Rogers, Sonia Sahgal, James Mitchell, Jacqueline Florio and Jeffrey W. Merola
Catalysts 2019, 9(6), 515; https://doi.org/10.3390/catal9060515 - 10 Jun 2019
Cited by 13 | Viewed by 4858
Abstract
Palladium(II) acetate reacts with proline and proline homologs in acetone/water to yield square planar bis-chelated palladium amino acid complexes. These compounds are all catalytically active with respect to oxidative coupling of olefins and phenylboronic acids. Some enantioselectivity is observed and formation of products [...] Read more.
Palladium(II) acetate reacts with proline and proline homologs in acetone/water to yield square planar bis-chelated palladium amino acid complexes. These compounds are all catalytically active with respect to oxidative coupling of olefins and phenylboronic acids. Some enantioselectivity is observed and formation of products not reported in other Pd(II) oxidative couplings is seen. The crystal structures of nine catalyst complexes were obtained. Extended lattice structures arise from N-H••O or O••(HOH)••O hydrogen bonding. NMR, HRMS, and single-crystal XRD data obtained on all are evaluated. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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12 pages, 4642 KiB  
Article
Facile Synthesis of P25@Pd Core-Shell Catalyst with Ultrathin Pd Shell and Improved Catalytic Performance in Heterogeneous Enantioselective Hydrogenation of Acetophenone
by Xiuyun Gao, Lulu He, Juntong Xu, Xueying Chen and Heyong He
Catalysts 2019, 9(6), 513; https://doi.org/10.3390/catal9060513 - 9 Jun 2019
Cited by 5 | Viewed by 3639
Abstract
Heterogeneous enantioselective hydrogenation is an ideal method for synthesizing important chiral compounds in pesticides and pharmaceuticals. Up to the present, supported noble-metal catalysts are most widely studied in heterogeneous enantioselective hydrogenations. However, it is found that the weak interactions existing on the surface [...] Read more.
Heterogeneous enantioselective hydrogenation is an ideal method for synthesizing important chiral compounds in pesticides and pharmaceuticals. Up to the present, supported noble-metal catalysts are most widely studied in heterogeneous enantioselective hydrogenations. However, it is found that the weak interactions existing on the surface of support may have negative effects on the enantioselectivity. Herein, a new category of TiO2 (Aeroxide® P25) supported Pd catalyst with ultrathin Pd shell was successfully prepared via a simple strategy based on the reduction of PdI carbonyl complex. Characterization results show that a well-dispersed ultrathin Pd shell with an average thickness of ~1.0 nm and a Pd loading of 36 wt.% was formed over the surface of P25 support. By excluding the negative weak interactions from the support, the P25@Pd core-shell catalyst with unique electronic properties of Pd exhibits higher activity and enantioselectivity than that of Pd/P25 catalyst prepared by the impregnation method and unsupported Pd black catalyst in the enantioselective hydrogenation of acetophenone. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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13 pages, 5249 KiB  
Article
Effect of Direct Reduction Treatment on Pt–Sn/Al2O3 Catalyst for Propane Dehydrogenation
by Jae-Won Jung, Won-Il Kim, Jeong-Rang Kim, Kyeongseok Oh and Hyoung Lim Koh
Catalysts 2019, 9(5), 446; https://doi.org/10.3390/catal9050446 - 14 May 2019
Cited by 25 | Viewed by 5270
Abstract
Pt–Sn/Al2O3 catalysts were prepared by the direct reduction method at temperatures from 450 to 900 °C, denoted as an SR series (SR450 to SR900 according to reduction temperature). Direct reduction was performed immediately after catalyst drying without a calcination step. [...] Read more.
Pt–Sn/Al2O3 catalysts were prepared by the direct reduction method at temperatures from 450 to 900 °C, denoted as an SR series (SR450 to SR900 according to reduction temperature). Direct reduction was performed immediately after catalyst drying without a calcination step. The activity of SR catalysts and a conventionally prepared (Cal600) catalyst were compared to evaluate its effect on direct reduction. Among the SR catalysts, SR550 showed overall higher conversion of propane and propylene selectivity than Cal600. The nano-sized dispersion of metals on SR550 was verified by transmission electron microscopy (TEM) observation. The phases of the bimetallic Pt–Sn alloys were examined by X-ray diffraction, TEM, and energy dispersive X-ray spectroscopy (EDS). Two characteristic peaks of Pt3Sn and PtSn alloys were observed in the XRD patterns, and these phases affected the catalytic performance. Moreover, EDS confirmed the formation of Pt3Sn and PtSn alloys on the catalyst surface. In terms of catalytic activity, the Pt3Sn alloy showed better performance than the PtSn alloy. Relationships between the intermetallic interactions and catalytic activity were investigated using X-ray photoelectron spectroscopy. Furthermore, qualitative analysis of coke formation was conducted after propane dehydrogenation using differential thermal analysis. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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21 pages, 3672 KiB  
Article
Energy Efficient and Intermittently Variable Ammonia Synthesis over Mesoporous Carbon-Supported Cs-Ru Nanocatalysts
by Masayasu Nishi, Shih-Yuan Chen and Hideyuki Takagi
Catalysts 2019, 9(5), 406; https://doi.org/10.3390/catal9050406 - 30 Apr 2019
Cited by 16 | Viewed by 4106
Abstract
The Cs-promoted Ru nanocatalysts supported on mesoporous carbon materials (denoted as Cs-Ru/MPC) and microporous activated carbon materials (denoted as Cs-Ru/AC) were prepared for the sustainable synthesis of ammonia under mild reaction conditions (<500 °C, 1 MPa). Both Ru and Cs species were homogeneously [...] Read more.
The Cs-promoted Ru nanocatalysts supported on mesoporous carbon materials (denoted as Cs-Ru/MPC) and microporous activated carbon materials (denoted as Cs-Ru/AC) were prepared for the sustainable synthesis of ammonia under mild reaction conditions (<500 °C, 1 MPa). Both Ru and Cs species were homogeneously impregnated into the mesostructures of three commercial available mesoporous carbon materials annealed at 1500, 1800 and 2100 °C (termed MPC-15, MPC-18 and MPC-21, respectively), resulting in a series of Cs-Ru/MPC catalysts with Ru loadings of 2.5–10 wt % and a fixed Cs loading of 33 wt %, corresponding to Cs/Ru molar ratios of 2.5–10. However, the Ru and Cs species are larger than the pore mouths of microporous activated carbon (shortly termed AC) and, as a consequence, were mostly aggregated on the outer surface of the Cs-Ru/AC catalysts. The Cs-Ru/MPC catalysts are superior to the Cs-Ru/AC catalyst in catalysing mild ammonia synthesis, especially for the 2.5Cs-10Ru/MPC-18 catalyst with a Ru loading of 10 wt % and a Cs/Ru ratio of 2.5, which exhibited the highest activity across a wide SV range. It also showed an excellent response and stability during cycling tests over a severe temperature jump in a short time, presumably due to the open mesoporous carbon framework and suitable surface concentrations of CsOH and metallic Ru species at the catalytically active sites. This 2.5Cs-10Ru/MPC-18 catalyst with high activity, fast responsibility and good stability has potential application in intermittently variable ammonia synthesis using CO2-free hydrogen derived from electrolysis of water using renewable energy with fast variability. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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15 pages, 2334 KiB  
Article
Differences in the Catalytic Behavior of Au-Metalized TiO2 Systems During Phenol Photo-Degradation and CO Oxidation
by Oscar H. Laguna, Julie J. Murcia, Hugo Rojas, Cesar Jaramillo-Paez, Jose A. Navío and Maria C. Hidalgo
Catalysts 2019, 9(4), 331; https://doi.org/10.3390/catal9040331 - 3 Apr 2019
Cited by 8 | Viewed by 3607
Abstract
For this present work, a series of Au-metallized TiO2 catalysts were synthesized and characterized in order to compare their performance in two different catalytic environments: the phenol degradation that occurs during the liquid phase and in the CO oxidation phase, which proceeds [...] Read more.
For this present work, a series of Au-metallized TiO2 catalysts were synthesized and characterized in order to compare their performance in two different catalytic environments: the phenol degradation that occurs during the liquid phase and in the CO oxidation phase, which proceeds the gas phase. The obtained materials were analyzed by different techniques such as XRF, SBET, XRD, TEM, XPS, and UV-Vis DRS. Although the metallization was not totally efficient in all cases, the amount of noble metal loaded depended strongly on the deposition time. Furthermore, the differences in the amount of loaded gold were important factors influencing the physicochemical properties of the catalysts, and consequently, their performances in the studied reactors. The addition of gold represented a considerable increase in the phenol conversion when compared with that of the TiO2, despite the small amount of noble metal loaded. However, this was not the case in the CO oxidation reaction. Beyond the differences in the phase where the reaction occurred, the loss of catalytic activity during the CO oxidation reaction was directly related to the sintering of the gold nanoparticles. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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12 pages, 4548 KiB  
Article
Immobilization of Stabilized Gold Nanoparticles on Various Ceria-Based Oxides: Influence of the Protecting Agent on the Glucose Oxidation Reaction
by Meriem Chenouf, Cristina Megías-Sayago, Fatima Ammari, Svetlana Ivanova, Miguel Angel Centeno and José Antonio Odriozola
Catalysts 2019, 9(2), 125; https://doi.org/10.3390/catal9020125 - 31 Jan 2019
Cited by 10 | Viewed by 3328
Abstract
The influence of the protecting agent’s nature on gold particle size and dispersion was studied in this work over a series of gold-based catalysts. CO and glucose oxidation were chosen as catalytic reactions to determine the catalyst’s structure–activity relationship. The nature of the [...] Read more.
The influence of the protecting agent’s nature on gold particle size and dispersion was studied in this work over a series of gold-based catalysts. CO and glucose oxidation were chosen as catalytic reactions to determine the catalyst’s structure–activity relationship. The nature of the support appeared to be the predominant factor for the increase in activity, as the oxygen mobility was decisive for the CO oxidation in the same way that the Lewis acidity was decisive for the glucose oxidation. For the same catalyst composition, the use of montmorillonite as the stabilizing agent resulted in better catalytic performance. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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14 pages, 3458 KiB  
Article
Properties of Carbon-supported Precious Metals Catalysts under Reductive Treatment and Their Influence in the Hydrodechlorination of Dichloromethane
by Alejandra Arevalo-Bastante, Maria Martin-Martinez, M. Ariadna Álvarez-Montero, Juan J. Rodriguez and Luisa M. Gómez-Sainero
Catalysts 2018, 8(12), 664; https://doi.org/10.3390/catal8120664 - 18 Dec 2018
Cited by 12 | Viewed by 3460
Abstract
This study analyzes the effect of the reduction temperature on the properties of Rh, Pt and Pd catalysts supported on activated carbon and their performance in the hydrodechlorination (HDC) of dichloromethane (DCM). The reduction temperature plays an important role in the oxidation state, [...] Read more.
This study analyzes the effect of the reduction temperature on the properties of Rh, Pt and Pd catalysts supported on activated carbon and their performance in the hydrodechlorination (HDC) of dichloromethane (DCM). The reduction temperature plays an important role in the oxidation state, size and dispersion of the metallic phase. Pd is more prone to sintering, followed by Pt, while Rh is more resistant. The ratio of zero-valent to electro-deficient metal increases with the reduction temperature, with that effect being more remarkable for Pd and Pt. The higher resistance to sintering of Rh and the higher stability of electro-deficient species under thermal reductive treatment can be attributed to a stronger interaction with surface oxygen functionalities. Dechlorination activity and a TOF increase with reduction temperature (250–450 °C) occurred in the case of Pt/C catalyst, while a great decrease of both was observed for Pd/C, and no significant effect was found for Rh/C. Pt0 represents the main active species for HDC reaction in Pt/C. Therefore, increasing the relative amount of these species increased the TOF value, compensating for the loss of dispersion. In contrast, Pdn+ appears as the main active species in Pd/C and their relatively decreasing occurrence together with the significant decrease of metallic area reduces the HDC activity. Rh/C catalyst suffered only small changes in dispersion and metal oxidation state with the reduction temperature and thus this variable barely affected its HDC activity. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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11 pages, 4366 KiB  
Article
Palladium Supported on Carbon Nanotubes as a High-Performance Catalyst for the Dehydrogenation of Dodecahydro-N-ethylcarbazole
by Mengyan Zhu, Lixin Xu, Lin Du, Yue An and Chao Wan
Catalysts 2018, 8(12), 638; https://doi.org/10.3390/catal8120638 - 8 Dec 2018
Cited by 34 | Viewed by 4852
Abstract
Hydrogen storage in the form of liquid organic hydrides, especially N-ethylcarbazole, has been regarded as a promising technology for substituting traditional fossil fuels owing to its unique merits such as high volumetric, gravimetric hydrogen capacity and safe transportation. However, unsatisfactory dehydrogenation has impeded [...] Read more.
Hydrogen storage in the form of liquid organic hydrides, especially N-ethylcarbazole, has been regarded as a promising technology for substituting traditional fossil fuels owing to its unique merits such as high volumetric, gravimetric hydrogen capacity and safe transportation. However, unsatisfactory dehydrogenation has impeded the widespread application of N-ethylcarbazole as ideal hydrogen storage materials in hydrogen energy. Therefore, designing catalysts with outstanding performance is of importance to address this problem. In the present work, for the first time, we have synthesized Pd nanoparticles immobilized on carbon nanotubes (Pd/CNTs) with different palladium loading through an alcohol reduction technique. A series of characterization technologies, such as X-ray diffraction (XRD), inductively coupled plasma-atomic emission spectrometer (ICP-AES), X-ray photoelectron spectroscopy (XPS) and transmission electron spectroscopy (TEM) were adopted to systematically explore the structure, composition, surface properties and morphology of the catalysts. The results reveal that the Pd NPs with a mean diameter of 2.6 ± 0.6 nm could be dispersed uniformly on the surface of CNTs. Furthermore, Pd/CNTs with different Pd contents were applied in the hydrogen release of dodecahydro-N-ethylcarbazole. Among all of the catalysts tested, 3.0 wt% Pd/CNTs exhibited excellent catalytic performance with the conversion of 99.6% producing 5.8 wt% hydrogen at 533 K, low activation energy of 43.8 ± 0.2 kJ/mol and a high recycling stability (>96.4% conversion at 5th reuse). Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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18 pages, 7093 KiB  
Article
Toward the Sustainable Synthesis of Propanols from Renewable Glycerol over MoO3-Al2O3 Supported Palladium Catalysts
by Shanthi Priya Samudrala and Sankar Bhattacharya
Catalysts 2018, 8(9), 385; https://doi.org/10.3390/catal8090385 - 9 Sep 2018
Cited by 22 | Viewed by 5013
Abstract
The catalytic conversion of glycerol to value-added propanols is a promising synthetic route that holds the potential to overcome the glycerol oversupply from the biodiesel industry. In this study, selective hydrogenolysis of 10 wt% aqueous bio-glycerol to 1-propanol and 2-propanol was performed in [...] Read more.
The catalytic conversion of glycerol to value-added propanols is a promising synthetic route that holds the potential to overcome the glycerol oversupply from the biodiesel industry. In this study, selective hydrogenolysis of 10 wt% aqueous bio-glycerol to 1-propanol and 2-propanol was performed in the vapor phase, fixed-bed reactor by using environmentally friendly bifunctional Pd/MoO3-Al2O3 catalysts prepared by wetness impregnation method. The physicochemical properties of these catalysts were derived from various techniques such as X-ray diffraction, NH3-temperature programmed desorption, scanning electron microscopy, 27Al NMR spectroscopy, surface area analysis, and thermogravimetric analysis. The catalytic activity results depicted that a high catalytic activity (>80%) with very high selectivity (>90%) to 1-propanol and 2-propanol was obtained over all the catalysts evaluated in a continuously fed, fixed-bed reactor. However, among all others, 2 wt% Pd/MoO3-Al2O3 catalyst was the most active and selective to propanols. The synergic interaction between the palladium and MoO3 on Al2O3 support and high strength weak to moderate acid sites of the catalyst were solely responsible for the high catalytic activity. The maximum glycerol conversion of 88.4% with 91.3% selectivity to propanols was achieved at an optimum reaction condition of 210 ∘ C and 1 bar pressure after 3 h of glycerol hydrogenolysis reaction. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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8 pages, 1215 KiB  
Article
Effect of Microwave Drying, Calcination and Aging of Pt/Al2O3 on Platinum Dispersion
by Xavier Auvray and Anthony Thuault
Catalysts 2018, 8(9), 348; https://doi.org/10.3390/catal8090348 - 26 Aug 2018
Cited by 9 | Viewed by 6545
Abstract
The effect of heating method employed for drying and calcination during the synthesis of 1 wt% Pt/Al2O3 catalyst was investigated. Conventional heating (CH) in resistive oven and microwave heating (MW) in single mode were applied, and the Pt dispersion and [...] Read more.
The effect of heating method employed for drying and calcination during the synthesis of 1 wt% Pt/Al2O3 catalyst was investigated. Conventional heating (CH) in resistive oven and microwave heating (MW) in single mode were applied, and the Pt dispersion and Brunauer-Emmett-Teller (BET) surface area were measured to characterize the samples. It was evidenced that the fast and homogeneous heating offered by the microwave heating led to higher Pt dispersion. However, this benefit was only achieved when the subsequent calcination was performed in a conventional oven. The aging in microwave oven of conventionally prepared—as well as MW-prepared—catalysts demonstrated the great ability of microwave irradiation to accelerate platinum sintering. After 1 h at 800 °C under microwave, catalysts showed a dispersion of 5%. Therefore, microwave treatment should be considered for accelerated catalyst aging but should be avoided as a calcination technique for the synthesis of highly dispersed Pt/Al2O3. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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Review

Jump to: Editorial, Research

24 pages, 2650 KiB  
Review
Perovskite Structure Associated with Precious Metals: Influence on Heterogenous Catalytic Process
by Guilhermina Ferreira Teixeira, Euripedes Silva Junior, Ramon Vilela, Maria Aparecida Zaghete and Flávio Colmati
Catalysts 2019, 9(9), 721; https://doi.org/10.3390/catal9090721 - 27 Aug 2019
Cited by 36 | Viewed by 5519
Abstract
The use of perovskite-based materials and their derivatives can have an important role in the heterogeneous catalytic field based on photochemical processes. Photochemical reactions have a great potential to solve environmental damage issues. The presence of precious metals in the perovskite structure (i.e., [...] Read more.
The use of perovskite-based materials and their derivatives can have an important role in the heterogeneous catalytic field based on photochemical processes. Photochemical reactions have a great potential to solve environmental damage issues. The presence of precious metals in the perovskite structure (i.e., Ag, Au, or Pt) may improve its efficiency significantly. The precious metal may comprise the perovskite lattice as well as form a heterostructure with it. The efficiency of catalytic materials is directly related to processing conditions. Based on this, this review will address the use of perovskite materials combined with precious metal as well as their processing methods for the use in catalyzed reactions. Full article
(This article belongs to the Special Issue Catalysis by Precious Metals, Past and Future)
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