2,137 results on '"SILVER catalysts"'
Search Results
2. Electrocatalytic nitrate removal from water using Ag- microparticles and Ag-Poly vinyl alcohol beads: a comparative study.
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Date, Manali, Jaspal, Dipika, and Patel, Upendra
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SILVER catalysts , *SCANNING electron microscopes , *GROUNDWATER , *DENITRIFICATION , *WATER sampling , *SILVER nitrate - Abstract
Excessive application of fertilisers and illegal land disposal of untreated industrial wastewater leads to mounting nitrate content in surface and ground water sources. Conventionally explored methods have their own limitations giving rise to the need for advanced methods which are cost-effective and cause complete destruction of nitrate. In the present study, electrocatalysis has been carried upon synthetic nitrate solutions and actual ground water samples containing nitrate. Silver microparticles (Ag-MP) and silver immobilised on poly vinyl alcohol (Ag-PVA beads) were applied at current density of 15 mA/cm2, 33–35°C and initial pH in a two-compartment cell with Cation Exchange Membrane (CEM) as separator, which is a completely novel approach. Scanning Electron Microscope (SEM) observation of the Ag-PVA beads was done to understand the composition and characterisation of the beads. Three concentrations of silver nitrate solutions i.e. 3.3 mM, 6.6 mM and 9.9 mM were used for the fabrication of silver catalyst. Maximum removal (96% for Ag-MP and 90% for Ag-PVA beads) was obtained with largest concentration (9.9 mM) of silver nitrate synthesised catalyst for synthetic nitrate solutions in both the cases. Selectivity of end product was towards nitrogen gas with sparse nitrite and negligible ammonical nitrogen formation. The destruction of nitrate was due to the nucleophile AgHx generated by Ag0 and the nascent hydrogen on catalystsurface. Conversion was higher using nanoparticles than by use of immobilised beads due to more specific surface area in the former. For ground water sample, tests were carried out at 15 mA/cm2 using 6.6 mM Ag-PVA beads and gave 63% of nitrate reduction with substantial formation of nitrate and some ammonia. [ABSTRACT FROM AUTHOR] more...
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- 2024
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Catalog
3. Silver‐Catalyzed Carbamoylation and Carbonylative Cyclization of Alkenes with Oxamic Acids.
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A, Ru‐Han, Bao, Zhi‐Peng, Huo, Yong‐Wang, and Wu, Xiao‐Feng
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ORGANIC chemistry , *SILVER catalysts , *RADICALS (Chemistry) , *ALKENES , *ACIDS - Abstract
Transition metal‐catalyzed carbonylation functionalization reaction of alkenes is an attractive research area in modern organic chemistry. However, there have been very few reports on silver‐catalyzed reactions in carbonylation reactions. Herein we developed a silver‐catalyzed carbamoylation and carbonylative cyclization of alkenes with oxamic acids to obtain 2‐acetylamino‐1‐tetralone derivatives. Various desired cyclized products were formed in moderate to good yields through radical intermediates. [ABSTRACT FROM AUTHOR] more...
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- 2024
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4. Dynamically Stabilizing Oxygen Atoms in Silver Catalyst for Highly Selective and Durable CO2 Reduction Reaction.
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Mao, Yuanxin, Mao, Qing, Yang, Hongbin, Liu, Qi, Dong, Xufeng, Li, Yifan, Zhou, Shizong, and Liu, Bin
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SILVER catalysts , *CATALYTIC activity , *ELECTRONIC structure , *ELECTROCHEMISTRY , *ATOMS , *ELECTROLYTIC reduction , *CARBON dioxide reduction - Abstract
Oxide derived catalyst displays outstanding catalytic activity and selectivity in electrochemical carbon dioxide reduction reaction (CO2RR), in which, it is found that residue oxygen atoms play a pivotal role in regulating the catalyst's electronic structure and thus the CO2RR process. Unfortunately, the intrinsic thermodynamic instability of oxygen atoms in oxide derived catalyst under cathodic CO2RR potentials makes it unstable during continuous electrolysis, greatly hindering its practical industrial applications. In this work, we develop a pulsed‐bias technique that is able to dynamically stabilize the residue oxygen atoms in oxide derived catalyst during electrochemical CO2RR. As a result, the oxide derived catalyst under pulsed bias exhibits super catalytic stability in catalyzing electrochemical CO2RR, while keeping excellent catalytic activity and selectivity. [ABSTRACT FROM AUTHOR] more...
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- 2024
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5. Giant Photodegradation Rate Enabled by Vertically Grown 1T/2H MoS2 Catalyst on Top of Silver Nanoparticles.
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Mouloua, Driss, Rajput, Nitul S, Lejeune, Michael, Beruete, Miguel, El Marssi, Mimoun, El Khakani, My Ali, and Jouiad, Mustapha
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SILVER nanoparticles ,RAMAN scattering ,ENVIRONMENTAL remediation ,SILVER catalysts ,WASTEWATER treatment - Abstract
The exaltation of the photodegradation performance of dichalcogenide MoS2 grown on top of silver nanoparticles (Ag‐NPs) is reported on. The fabricated MoS2 nanosheets nucleate vertically from Ag‐NPs seeds, enabling the growth of both metallic and semiconductor phases 1T/2H‐MoS2. Findings reveal remarkable enhancement of the Raman scattering and an exceptional broadband optical absorption attributed to plasmonic effects induced by the presence of both metallic 1T‐MoS2 and Ag‐NPS at 2H‐MoS2 interfaces. To leverage this effect, photodegradation tests are conducted to remove methyl orange pollutant. Notably, results reveal a significant increase in photodegradation efficiency and rate constant, reaching up to 120% and 550% over pristine 2H‐MoS2, respectively. This finding underscores the role of Ag‐NPs and 1T‐MoS2 tandem to unlock the superior photodegradation properties of vertically aligned 2H‐MoS2 toward methyl orange, paving the way for the development of dichalcogenide‐based hybrid photocatalyst for wastewater treatment and environmental remediation. [ABSTRACT FROM AUTHOR] more...
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- 2024
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6. Design a well-dispersed Ag-based/CoFe2O4–CNT catalyst for hydrogen production via NaBH4 hydrolysis.
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Abdel-Salam, M.O., Kim, Youngsoo, Moustafa, Yasser M., and Yoon, Taeho
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CHEMICAL kinetics , *GREEN fuels , *HYDROGEN production , *INTERSTITIAL hydrogen generation , *SILVER catalysts , *SILVER - Abstract
Green hydrogen is a crucial element in the hydrogen value chain, encompassing hydrogen production, transportation, storage, and application. The production of green hydrogen via NaBH 4 hydrolysis (SBH) entails a high cost. However, the fast kinetics of this process with a catalyst compensate for the substantial cost, especially in specific applications, such as local or intermittent use. Silver is known for its excellent catalytic properties. Its high catalytic activity is a key factor in achieving efficient hydrogen generation from (SBH). In this study, a nanocomposite catalyst composed of silver nanoparticles (AgNPs), CoFe 2 O 4 , and carbon nanotubes (CNT) was investigated to demonstrate an effective catalyst design approach to achieve enhanced hydrogen generation performance. The H 2 production rate in the presence of Ag-based/CoFe 2 O 4 –CNT was 320 mL min−1 g−1, and the apparent activation energy was 14.7 kJ mol−1, superior to that of Ag-based catalysts reported in the literature. Analyses of the observed outcomes revealed that the CNT was decorated with well-dispersed AgNPs and CoFe 2 O 4 nanoparticles. The synergistic effects of AgNPs, CoFe 2 O 4 , and CNT were demonstrated by analyzing the kinetic behaviour of each component based on systematic comparisons. Furthermore, the paramagnetic property of CoFe 2 O 4 enables harvesting of the catalyst using an external magnetic field, and it was verified that the reactivity of the collected catalyst was maintained throughout seven successive cycles. The outstanding catalytic performance of Ag/CoFe 2 O 4 – CNT should be attributed to the uniform dispersion of nanoparticles on the CNT surface. Furthermore, our key approach for developing efficient Ag-based carbon advanced catalysts for SBH in the future is to ensure their suitability for industrial applications. Graphical illustration for the hydrogen production by hydrolysis process. [Display omitted] • A magnetic Ag/CoFe 2 O 4 -carbon nanotube nanocomposite was designed and synthesized. • Highly dispersed CoFe 2 O 4 and AgNPs are evenly embedded on the CNT. • Reaction kinetics followed during hydrogen production under different experimental conditions have been investigated. • The ACC catalyst demonstrated high activity, good recyclability, and low activation energy. [ABSTRACT FROM AUTHOR] more...
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- 2024
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7. Fine-tuning syngas composition using laser surface modified silver electrode for CO2 electroreduction.
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McKee, Austin, Huang, Wuji, Shen, Ninggang, Mubeen, Syed, and Ding, Hongtao
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SYNTHETIC natural gas ,SILVER catalysts ,SYNTHETIC fuels ,STANDARD hydrogen electrode ,CONTACT angle ,ELECTROLYTIC reduction - Abstract
Electrochemical reduction of CO
2 and H2 O to synthesize gas (H2 and CO mixture) is of significant interest due to established industrial pathways to tune the H2 to CO composition to generate an array of valuable products including methanol, synthetic fuel, synthetic natural gas, and hydrogen. However, controlled H2 :CO ratios are challenging on CO-active electrocatalysts like silver. We demonstrate that applying laser engineering to adjust the surface wetting state of a silver electrocatalyst with water contact angles θw ranging from 47° and 135°, H2 :CO ratios can be tuned from 1 to 4 at modest potentials (−0.7 V versus RHE, RHE—reversible hydrogen electrode) with almost total unity Faradaic efficiency. Both hydrophilic (θw = 47°) and more hydrophobic (θw = 135°) samples showed an increasing H2 :CO trend with rising potentials (0.7–1.2 V versus RHE) due to mass transport. Conversely, silver electrocatalyst with θw = 110° exhibited a constant H2 :CO ratio of 4. This indicates catalyst wettability potentially affects *H and *HOCO intermediates' adsorption, impacting H2 :CO ratios. Our results show the feasibility of syngas composition control on silver catalysts via surface wettability, providing a simpler alternative to complex multicomponent electrocatalytic systems. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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8. Anchoring Cs+ Ions on Carbon Vacancies for Selective CO2 Electroreduction to CO at High Current Densities in Membrane Electrode Assembly Electrolyzers.
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Sun, Yanhui, Chen, Junxiang, Du, XueMei, Cui, Jiwei, Chen, Xin, Wu, Chenhe, Yang, Xinmin, Liu, Lequan, and Ye, Jinhua
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HYDROGEN evolution reactions , *SILVER catalysts , *ENERGY conversion , *DENSITY functional theory , *SOLAR cells , *ELECTROLYTIC reduction - Abstract
Electrolyte cations have been demonstrated to effectively enhance the rate and selectivity of the electrochemical CO2 reduction reaction (CO2RR), yet their implementation in electrolyte‐free membrane electrode assembly (MEA) electrolyzer presents significant challenges. Herein, an anchored cation strategy that immobilizes Cs+ on carbon vacancies was designed and innovatively implemented in MEA electrolyzer, enabling highly efficient CO2 electroreduction over commercial silver catalyst. Our approach achieves a CO partial current density of approximately 500 mA cm−2 in the MEA electrolyzer, three‐fold enhancement compared to pure Ag. In situ Raman and theoretical analyses, combined with machine learning potentials, reveal anchored Cs induces an electric field that significantly promotes the adsorption of *CO2− intermediates through performing muti‐point energy calculations on each structure. Furthermore, reduced adsorption of *OH intermediates effectively hampers competing hydrogen evolution reaction, as clarified by disk electrode experiments and density functional theory studies. Additionally, coupling our system with commercial polysilicon solar cells yields a notable solar‐to‐CO energy conversion efficiency of 8.3 %. This study opens a new avenue for developing effective cation‐promoting strategy in MEA reactors for efficient CO2RR. [ABSTRACT FROM AUTHOR] more...
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- 2024
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9. Silver‐Catalyzed Decarboxylative Radical Cyclizations: Developments and Insights.
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Das, Suven and Dutta, Arpita
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SILVER salts ,SILVER catalysts ,CHARGE exchange ,RADICALS (Chemistry) ,AMINO acids ,CARBOXYLIC acids - Abstract
Transition‐metal‐catalyzed decarboxylative cross‐coupling reaction provides a powerful method for the construction C−C, C−N, C−O bonds, which have great impact on synthetic chemistry. The use of silver salts as catalyst in decarboxylative reaction gradually increases because of their easy availability, low toxicity, biocompatibility and adequate stability. In fact, various radical cyclization reactions have been accomplished by exploiting single electron transfer (SET) ability of silver salts. The present review highlights recent advances (2015‐mid 2023) in the silver‐catalyzed decarboxylative radical cyclizations for the construction of cyclic molecular scaffolds. The content of the review is organized on the basis of decarboxylative reagents, such as, α‐keto acids, aliphatic/aromatic carboxylic acids, α,α‐difluoroacetic acids, amino acids, alkynyl carboxylic acids, oxamic acids and miscellaneous acids. Additionally, mechanistic insights of most of the reactions are highlighted for well understanding of the reaction mode. [ABSTRACT FROM AUTHOR] more...
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- 2024
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10. Experimental Demonstration of the Production of Hydrogen and Water‐Free Formaldehyde Using Sodium Vapor.
- Author
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Kamienowska, Marta, Deutschmann, Max Philipp, Bender, Michael, Stoppel, Leonid, Daubner, Markus, Wetzel, Thomas, and Niedermeier, Klarissa
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SODIUM compounds , *SILVER catalysts , *SILVER oxide , *HYDROGEN production , *DEHYDROGENATION - Abstract
Conventional routes for the production of formaldehyde rely on the use of methanol and air, with the presence of catalysts such as silver or mixed‐metal oxides. These processes are highly energy intensive and therefore raise concerns in terms of cost‐effectiveness and environmental impact. In that respect, sodium or sodium compounds are more favorable as catalysts for the direct dehydrogenation of methanol to water‐free formaldehyde. A method is presented for the coproduction of hydrogen and anhydrous formaldehyde – both valuable products – on the laboratory scale, with a particular focus on the design and testing of a sodium vapor catalyst dosing unit that enables the process to be performed continuously. [ABSTRACT FROM AUTHOR] more...
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- 2024
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11. Silver‐Catalyzed Olefination of Aryl Aldehydes Using Propiolates.
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Manwar, Rina Raju and Balamurugan, Rengarajan
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WITTIG reaction , *OLEFINATION reactions , *SILVER catalysts , *ORGANIC synthesis , *REDUCING agents - Abstract
Olefination of aldehydes is one of the fundamental reactions in organic synthesis. The commonly used Wittig olefination reaction however uses stoichiometric quantities reagents under basic conditions resulting in stoichiometric amounts of byproducts. Known catalytic alternate to the Wittig reaction requires stoichiometric amounts of silane reducing agents and high temperature. Herein, we report a base‐free olefination of aryl aldehydes using propiolates as a surrogate for the Witting reagent under silver catalysis. Trimethyl orthoformate, in the presence of a silver catalyst adds to the alkynoate to form the nucleophilic silver allenolate which reacts with the reactive oxocarbenium ion formed from aldehyde under the reaction conditions. Subsequently, decarbonylation occurs to form the olefin. Trans olefin is formed exclusively from simple aryl aldehydes and cinnamaldehydes. Such a silver allenolate is conceptually novel and has not been explored so far. [ABSTRACT FROM AUTHOR] more...
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- 2024
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12. Oxide‐Encapsulated Silver Electrocatalysts for Selective and Stable Syngas Production from Reactive Carbon Capture Solutions.
- Author
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Lin, Zhexi, Blake, Nathaniel, Pang, Xueqi, He, Zhirui, Mirshekari, Gholamreza, Romiluyi, Oyinkansola, Son, Yoon Jun, Kabra, Suryansh, and Esposito, Daniel V.
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CARBON sequestration , *SILVER catalysts , *HYDROGEN evolution reactions , *ELECTROLYSIS , *BICARBONATE ions , *CHELATING agents , *ETHYLENEDIAMINETETRAACETIC acid - Abstract
Electrolysis of bicarbonate‐containing CO2 capture solutions is a promising approach towards achieving low‐cost carbon‐neutral chemicals production. However, the parasitic bicarbonate‐mediated hydrogen evolution reaction (HER) and electrode instability in the presence of trace impurities remain major obstacles to overcome. This work demonstrates that the combined use of titanium dioxide (TiO2) overlayers with the chelating agent ethylene diamine tetra‐acetic acid (EDTA) significantly enhances the selectivity and stability of Ag‐based electrocatalysts for bicarbonate electrolysis. The amorphous TiO2 overlayers suppress the HER by over 50 % at potentials more negative than −0.7 V vs. RHE, increasing the CO faradaic efficiency (FE) by 33 % (relative). In situ surface‐enhanced Raman spectroscopy (SERS) measurements reveal the absence of near‐surface bicarbonate species and an abundance of CO2 reduction intermediates at the Ag|TiO2 buried interface, suggesting that the overlayers suppress HER by blocking bicarbonate ions from reaching the buried active sites. In accelerated degradation tests with 5 ppm of Fe(III) impurity, the addition of EDTA allows stable CO production with >47 % FE, while the electrodes rapidly deactivate in the absence of EDTA. This work highlights the use of TiO2 overlayers for enhancing the CO : H2 ratio while simultaneously protecting electrocatalysts from impurities likely to be present in "open" carbon capture systems. [ABSTRACT FROM AUTHOR] more...
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- 2024
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13. Green Synthesis of Ag/ATP Catalysts Using Clove Extract for Formaldehyde Elimination.
- Author
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Hu, Yuan, Chen, Xin, Miao, Liqi, Zhang, Jing, Zhai, Ming, Chen, Dan, and Wang, Xiaozhi
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SILVER catalysts ,TRANSMISSION electron microscopes ,METAL nanoparticles ,CATALYTIC oxidation ,PLANT extracts ,SILVER nanoparticles ,SILVER - Abstract
Compared with other methods, the synthesis of metal nanoparticles by metal ion reduction using plant extracts as raw materials has the advantages of low cost, simple synthesis and environmental friendliness, and has garnered significant attention. To achieve this effect, in the form of green synthetic nano silver (AgNP), we mixed AgNO
3 with attapulgite (ATP) and stirred it with clove plant extract at 80 °C. By changing the dosage of clove extract, a series of new samples were prepared by the same method. The shape and size of the synthesized silver nanoparticles on catalysts were visualized by transmission electron microscope (TEM) observations. The particle size of the optimally prepared nanoparticles ranges from 1 to 9 nm with spherical or roughly spherical forms. The inductively coupled plasma (ICP) results further demonstrated the reducing effect of clove extract on Ag. Increasing the amount of clove extract could promote the formation and loading of Ag on ATP. An outstanding catalytic performance of Ag/ATP under HCHO outperformed that synthesized without clove extract. With the addition of clove extract, the catalytic performance was enhanced by more than 40% compared to no addition. Among different nanoparticles, the catalytic oxidation activity of HCHO was best when the volume ratio of clove extract to Ag was 10:1. Therefore, the green synthesis of Ag/ATP catalysts using clove extracts can be considered an environmentally benign, superior approach. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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14. A study of 50% liquid H2O2 decomposition on a silver catalyst for CubeSat applications.
- Author
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Parittothok, P., Promoppatum, P., and Wongwiwat, J.
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SILVER catalysts , *CUBESATS (Artificial satellites) , *SPACE exploration , *PROPELLANTS , *HYDROGEN peroxide , *SCIENTIFIC observation - Abstract
At present, microsatellites or CubeSats are widely used for various purposes including Earth observation, spacecraft technology demonstration, and scientific experiments. In general, CubeSat orbital time can be extended with an integrated micro-thruster. However, a CubeSat is too small to fit a conventional thruster. Therefore, a small-scale monopropellant thruster has been developed to extend the CubeSat orbital time. With the concept of a monopropellant thruster, 50% W/W hydrogen peroxide (H2O2) was used as a propellant, and silver pellets were used as a catalyst. Hydrogen peroxide was initially stored in a pressurized stainless-steel tank and the flow rate was controlled by adjusting the pulse per minute of the solenoid valve to flow the hydrogen peroxide through the catalyst chamber at up to 1.25 mL/min. Type K thermocouples are placed at the exhaust and at the center of the chamber, which is filled with 1.7-mm mean-diameter silver pellets, to measure the temperature from the reaction. Temperature data were recorded using a NI-cDAQ during testing. The decomposition of H2O2 and silver catalyst produced water (H2O), oxygen (O2), and a significant amount of heat. It was found from the experiment that the activation energy of H2O2 decomposition was 36.59 kJ/mol and the pre-exponential factor was 13.3×108 1/s. This study demonstrated a method to estimate reaction rate constants of H2O2 which will benefit the further development of micro-thrusters for CubeSat applications. The use of a small-scale monopropellant thruster can extend the CubeSat orbital time and facilitate various scientific experiments and observations. It is exciting to see the advancements in CubeSat technology and the potential benefits it can bring to space exploration and research. [ABSTRACT FROM AUTHOR] more...
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- 2024
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15. Recent advances in silver-mediated/catalyzed synthesis of trifluoromethoxy compounds
- Author
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Altaf, Muhammad Bilal, Luan, Yu-Xin, and Tang, Pingping
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- 2024
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16. Internal 2D networking of silver bromide with a bidentate N-heterocyclic carbene ligand enables the formation of an inherently heterogeneous reusable catalyst for multicomponent A3 coupling.
- Author
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Nallappan, Sundaravelu, Kucherak, Oleksandr, Kiss, Anita, Lapinskaite, Ringaile, Císařová, Ivana, and Rycek, Lukas
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HETEROGENEOUS catalysts , *SILVER bromide , *SILVER catalysts , *COUPLING reactions (Chemistry) , *INORGANIC polymers , *CARBENE synthesis , *CROSSLINKED polymers , *ORGANIC solvents - Abstract
We report the synthesis of a heterogenous silver catalyst stabilized by bidentate N-heterocyclic carbene ligands. The heterogeneous nature of the catalyst is inherently derived from the unprecedented internal structural features observed for the catalyst. X-ray studies show that the silver complex forms a two-dimensional cross-linked system, where one dimension of the network is formed by inorganic polymer strings and the second direction is formed by the interconnection of these inorganic strings with NHC bidentate ligands. This organized internal arrangement renders the complex insoluble in many common organic solvents and enables its utilization as a reusable heterogeneous catalyst in multicomponent A3 coupling reactions. Notably, propargylic amines were obtained with yields of up to 97%, and the catalyst demonstrated reusability for six cycles. These results can facilitate the further development of heterogeneous NHC catalysts. [ABSTRACT FROM AUTHOR] more...
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- 2024
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17. BIOGENICALLY SYNTHESIZED SILVER NANOPARTICLES CATALYZED OXIDATION OF ALIPHATIC AND CYCLIC ALCOHOLS BY KIO4: KINETIC AND THERMODYNAMIC STUDY.
- Author
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Tiwari, Anjali, Prabhu, D. V., and Parbat, Harichandra A.
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SILVER nanoparticles , *SILVER catalysts , *JUJUBE (Plant) , *MANUFACTURING processes , *OXIDATION kinetics - Abstract
The ability to generate valuable products through oxidation makes it one of the most pivotal industrial processes. While organic oxidants have traditionally been the focus in converting alcohols into carbonyl compounds, inorganic oxidants have been relatively underutilized. In this study, we delve into the influence of Potassium periodate (KIO4) in an acidic environment on the oxidation of selected alcohols, comparing its performance with that of catalyst silver nanoparticles prepared from two distinct plant sources: Madhuca longifolia flowers and Ziziphus jujuba leaves. The reactions were intentionally conducted under conditions that adhere to first-order kinetics. At regular intervals throughout the reaction, iodometric measurements were employed to monitor the progress of the reaction. It was noted that the oxidation rate exhibited a proportional increase corresponding to the concentration of alcohol for all the alcohols examined, while it decreased with an increasing concentration of the oxidant. In contrast, when AgNP catalysts were employed in conjunction with KIO4, significantly higher rate constants were achieved compared to using KIO4 alone. This research underscores the potential of silver nanoparticles prepared from plant sources as effective catalysts for alcohol oxidation, offering promising avenues for the development of more efficient and sustainable oxidation processes in the industry. [ABSTRACT FROM AUTHOR] more...
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- 2024
- Full Text
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18. Wet-Chemical Fabrication of Functional Humidity Sensors on a TiO 2 -Coated Glass Substrate via UV Photodeposition.
- Author
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Stefanov, Bozhidar I.
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SILVER catalysts ,SUBSTRATES (Materials science) ,TITANIUM dioxide ,COPPER ,HUMIDITY ,ELECTROLESS deposition ,NICKEL oxide - Abstract
This work demonstrates a completely wet-chemical procedure for the fabrication of a functional impedimetric humidity-sensing device on a titania (TiO
2 ) surface. Optically transparent anatase TiO2 thin films were deposited on a glass substrate via dip-coating from a titanium tetraisopropoxide (TTIP)–acetylacetonate (AA)-based sol and surface-functionalized with a nickel oxide (NiOx ) layer by ultraviolet (UV) photodeposition. Photodeposition was employed to form the interdigitated electrode pattern on the TiO2 surface as well through activation with a silver catalyst to promote electroless copper deposition. The relative humidity (RH) response of the pristine TiO2 - and NiOx /TiO2 -functionalized sensors was studied by impedance (Z) measurements in the 15%–90% RH range. It was found that while NiOx functionalization significantly dampens the RH–Z functional dependence, it improves its overall linearity and may successfully be employed for the purposeful design of titania-based sensing devices. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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19. Investigating the Catalytic Efficiency of Supported NHC‐Ag(I) Complexes in the Borono‐Minisci Reaction.
- Author
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Moroni, Giada, Bombonato, Elena, Bonafè, Samuele, Di Michele, Alessandro, Presenti, Sara, Guariento, Sara, Marcaccio, Massimo, Sardella, Roccaldo, Ronchi, Paolo, and Gioiello, Antimo
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REDUCTION potential , *SILVER catalysts , *CHEMICAL kinetics , *CATALYSTS , *FLOW chemistry - Abstract
A series of supported N‐heterocyclic carbene silver complexes (NHC‐Ag(I)) were prepared and characterized as catalysts for the borono‐Minisci reaction. After characterization, the synthesized catalysts were evaluated in batch mode to determine the reaction performance and kinetics. Interestingly, cyclic voltammetric analysis showed that the structure of both the complex and the ligand significantly influences the Ag(I)/Ag(II) redox potential and, in turn, the catalytic efficiency. Among the tested catalysts, the Si‐supported NHC‐Ag(I) 6 afforded the desired products in good to excellent yields in only 15 min, providing a complementary tactic to standard homogeneous approaches. [ABSTRACT FROM AUTHOR] more...
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- 2024
- Full Text
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20. Process Design for the Directly Coupled Production of Methanol and Formaldehyde Based on CO2.
- Author
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Münzer, Pia, Arnold, Ulrich, and Sauer, Jörg
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METHANOL production , *FORMALDEHYDE , *SILVER catalysts , *INTERSTITIAL hydrogen generation , *METHANOL as fuel , *INDUSTRIAL costs - Abstract
Sustainable hydrogen generation is preferred over production from fossil sources in the context of a carbon‐neutral economy. As a result, production costs for CO2‐based products are estimated to be much higher than those of their fossil equivalents. Hence, it is essential to optimize process chains regarding their hydrogen efficiency. In this study, a concept for the directly coupled production of CO2‐based methanol and formaldehyde in a modified silver catalyst process is evaluated regarding the utilization of H2. Detailed simulations in Aspen Plus allow the comparison to the separately operated synthesis of green methanol and formaldehyde. By directly connecting both production steps, utilization ratios of introduced H2 and CO2 could be improved, reaching values of 98 % and 99 %, respectively. [ABSTRACT FROM AUTHOR] more...
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- 2024
- Full Text
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21. Enhancing light trapping efficiency: Germanium-coated porous silicon structures for optimal antireflection performance.
- Author
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Ali, Adnan, Hussain, M. Sharafat, Almufarij, Rasmiah S., Ali, M. Yasir, Alharbe, Lamiaa G., Somaily, H.H., Shokralla, Elsammani Ali, Alrefaee, Salhah Hamed, Ashfaq, Arslan, and Abd-Elwahed, A.R.
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POROUS silicon , *PHOTOELECTRICITY , *SILVER catalysts , *POROUS metals , *METAL coating , *SILICON alloys , *GERMANIUM - Abstract
Porous silicon structures are effective in trapping light due to the abundance of pores on their surface, finding widespread use in optical applications like photoelectric conversion, photon collection, and detection. We have successfully created micro-porous silicon with exceptionally high antireflection performance through electrochemical etching using different concentrations of silver catalysts. Results show that this germanium coated porous silicon structure has a smaller range of pore sizes, leading to a reduced reflectivity of 2.6 % under light radiation with wavelengths. To understand the antireflective mechanism further, we explored the surface reflectivity of porous silicon structures by coating the germanium metal on the porous structure. Importantly, germanium coated porous silicon structures with high surface quality and well-preserved pore integrity are identified as beneficial for achieving lower reflectivity in the incident light wavelength range of 300–1200 nm. These findings are significant for the design of porous silicon antireflective materials. [ABSTRACT FROM AUTHOR] more...
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- 2024
- Full Text
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22. Process Design for the Directly Coupled Production of Methanol and Formaldehyde Based on CO2.
- Author
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Münzer, Pia, Arnold, Ulrich, and Sauer, Jörg
- Subjects
METHANOL production ,FORMALDEHYDE ,SILVER catalysts ,INTERSTITIAL hydrogen generation ,METHANOL as fuel ,INDUSTRIAL costs - Abstract
Sustainable hydrogen generation is preferred over production from fossil sources in the context of a carbon‐neutral economy. As a result, production costs for CO2‐based products are estimated to be much higher than those of their fossil equivalents. Hence, it is essential to optimize process chains regarding their hydrogen efficiency. In this study, a concept for the directly coupled production of CO2‐based methanol and formaldehyde in a modified silver catalyst process is evaluated regarding the utilization of H2. Detailed simulations in Aspen Plus allow the comparison to the separately operated synthesis of green methanol and formaldehyde. By directly connecting both production steps, utilization ratios of introduced H2 and CO2 could be improved, reaching values of 98 % and 99 %, respectively. [ABSTRACT FROM AUTHOR] more...
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- 2024
- Full Text
- View/download PDF
23. Chemical solution deposition of a (GaAl)2O3 single layer with high thickness and silver-enhanced crystal quality.
- Author
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Tang, Xiao, AlQanbar, Wesam A., Hassine, Mohamed Ben, Lu, Yi, Cao, Haicheng, Wang, Chuanju, Jiang, Zixian, Liu, Tingang, Xiao, Na, Nong, Mingtao, Khandelwal, Vishal, and Li, Xiaohang
- Subjects
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CHEMICAL solution deposition , *SILVER nitrate , *SILVER , *SILVER catalysts , *CRYSTALS , *MASS production , *EPITAXY - Abstract
Traditional chemical solution deposition (CSD) methods for growing Ga2O3 films face two main issues: limited thickness per deposition, necessitating multiple coating-annealing cycles for adequate film thickness, and a decline in crystal quality with increased thickness. This study introduces an innovative CSD technique for fabricating (GaAl)2O3 films, achieving both high thickness and superior crystal quality, where the aluminum content results from the diffusion of aluminum from sapphire substrates during annealing. The technique uses a precursor solution with high viscosity and cation concentration, allowing single-layer thicknesses of up to 180 nm. Additionally, the incorporation of silver nitrate for silver doping enhances nucleation, growth, and epitaxial quality, inducing a unique twelve-fold symmetry in the (−201) oriented (GaAl)2O3 films. Notably, silver serves as a catalyst and largely evaporates at high temperatures, thus preserving the film's final composition and performance. This study highlights the effectiveness of this CSD approach in simultaneously improving crystal quality and achieving desired film thickness, making it a promising method for mass production of high-quality (GaAl)2O3 films. [ABSTRACT FROM AUTHOR] more...
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- 2024
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24. Testing functional anchor groups for the efficient immobilization of molecular catalysts on silver surfaces.
- Author
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Bunjes, Ole, Rittmeier, Alexandra, Hedman, Daniel, Hua, Shao-An, Paul, Lucas A., Meyer, Franc, Ding, Feng, and Wenderoth, Martin
- Subjects
- *
SILVER catalysts , *NUCLEAR magnetic resonance spectroscopy , *SCANNING tunneling microscopy , *FUNCTIONAL groups , *CARBON dioxide reduction , *INFRARED absorption , *SUBLIMATION (Chemistry) - Abstract
Modifications of complexes by attachment of anchor groups are widely used to control molecule-surface interactions. This is of importance for the fabrication of (catalytically active) hybrid systems, viz. of surface immobilized molecular catalysts. In this study, the complex fac-Re(S-Sbpy)(CO)3Cl (S-Sbpy = 3,3′-disulfide-2,2′-bipyridine), a sulfurated derivative of the prominent Re(bpy)(CO)3Cl class of CO2 reduction catalysts, was deposited onto the clean Ag(001) surface at room temperature. The complex is thermostable upon sublimation as supported by infrared absorption and nuclear magnetic resonance spectroscopy. Its anchoring process has been analyzed using scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. The growth behavior was directly contrasted to the one of the parent complex fac-Re(bpy)(CO)3Cl (bpy = 2,2′-bipyridine). The sulfurated complex nucleates as single molecule at different surface sites and at molecule clusters. In contrast, for the parent complex nucleation only occurs in clusters of several molecules at specifically oriented surface steps. While this shows that surface immobilization of the sulfurated complex is more efficient as compared to the parent, symmetry analysis of the STM topographic data supported by DFT calculations indicates that more than 90% of the complexes adsorb in a geometric configuration very similar to the one of the parent complex. Thiolate groups are promising anchors to immobilize catalysts, particularly on coinage metal surfaces, but the anchor group's impact on the local adsorption configuration of the catalyst is often overlooked. Here, the authors study a sulfurated derivative of the prominent Re(bpy)(CO)3Cl carbon dioxide reduction catalysts on a Ag(001) surface at room temperature. [ABSTRACT FROM AUTHOR] more...
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- 2024
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25. Plastron effect enhanced electrochemical CO2 reduction activity over hydrophobic three-dimensional nanoporous silver.
- Author
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Xue, Yu, Zhu, Yingming, He, Chuan, Wu, Kejing, Liu, Yingying, Wang, Binshen, Lu, Houfang, and Liang, Bin
- Subjects
- *
SILVER catalysts , *MASS transfer , *CONTACT angle , *ELECTROLYTIC reduction , *AQUEOUS solutions , *HYDROPHOBIC surfaces , *SILVER - Abstract
The electrochemical reduction of CO2 on catalyst surfaces is hindered by the inefficient mass transfer of CO2 in aqueous solutions. In this study, we employed an electrochemical reduction approach to fabricate a hydrophobic three-dimensional nanoporous silver catalyst with a plastron effect, aiming to enhance the CO2 diffusion. The resulting catalyst exhibited an exceptional performance with the FECO peaking at 95% at −0.65 V (vs. RHE) and demonstrated remarkable stability during continuous electrolysis for 48 hours. Control experiments, together with Tafel analysis, EIS measurements, and contact angle results, confirmed that the notable enhancement of performance was attributed to the hydrophobic porous structure that facilitated efficient storage and rapid mass transfer of low-solubility CO2 gas reactants. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
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26. Catalytic Epoxidation Reaction.
- Author
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Leveneur, Sébastien, Tolvanen, Pasi, and Russo, Vincenzo
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- *
EPOXIDATION , *GRAPE seed oil , *SUPERCRITICAL carbon dioxide , *SILVER catalysts , *PROPYLENE oxide , *PINENE - Abstract
This document is a summary of a special issue of the journal Catalysts titled "Catalytic Epoxidation Reaction." The special issue focuses on the research efforts in catalyst and process intensification in the epoxidation of various substances, including gaseous molecules, molecules in multiphase, triglycerides, terpenes, and olefins. The special issue includes nine research articles and two reviews, covering topics such as kinetic modeling, catalyst preparation and characterization, and enzymatic catalysis. The articles provide insights into the epoxidation process and offer potential advancements for future research in this field. [Extracted from the article] more...
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- 2024
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27. Extrinsic hydrophobicity-controlled silver nanoparticles as efficient and stable catalysts for CO2 electrolysis.
- Author
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Ko, Young-Jin, Lim, Chulwan, Jin, Junyoung, Kim, Min Gyu, Lee, Ji Yeong, Seong, Tae-Yeon, Lee, Kwan-Young, Min, Byoung Koun, Choi, Jae-Young, Noh, Taegeun, Hwang, Gyu Weon, Lee, Woong Hee, and Oh, Hyung-Suk more...
- Subjects
SILVER nanoparticles ,COMPUTED tomography ,ELECTROLYTIC reduction ,ELECTROCATALYSTS ,HYDROGEN evolution reactions ,ELECTROLYSIS ,SILVER catalysts ,MASS transfer ,PHOTOCATHODES - Abstract
To realize economically feasible electrochemical CO
2 conversion, achieving a high partial current density for value-added products is particularly vital. However, acceleration of the hydrogen evolution reaction due to cathode flooding in a high-current-density region makes this challenging. Herein, we find that partially ligand-derived Ag nanoparticles (Ag-NPs) could prevent electrolyte flooding while maintaining catalytic activity for CO2 electroreduction. This results in a high Faradaic efficiency for CO (>90%) and high partial current density (298.39 mA cm‒2 ), even under harsh stability test conditions (3.4 V). The suppressed splitting/detachment of Ag particles, due to the lipid ligand, enhance the uniform hydrophobicity retention of the Ag-NP electrode at high cathodic overpotentials and prevent flooding and current fluctuations. The mass transfer of gaseous CO2 is maintained in the catalytic region of several hundred nanometers, with the smooth formation of a triple phase boundary, which facilitate the occurrence of CO2 RR instead of HER. We analyze catalyst degradation and cathode flooding during CO2 electrolysis through identical-location transmission electron microscopy and operando synchrotron-based X-ray computed tomography. This study develops an efficient strategy for designing active and durable electrocatalysts for CO2 electrolysis. A key factor for the electrochemical reduction of CO2 to CO is limiting the competing H2 evolution reaction. Here, authors use real-time synchrotron X-ray computed tomography to show that a silver nanoparticle-ligand catalyst structure improves water management, thereby maintaining CO production. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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28. Tailoring the Electronic Metal‐Support Interactions in Supported Silver Catalysts through Al modification for Efficient Ethylene Epoxidation.
- Author
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Yang, Hongling, Li, Ganggang, Liu, Qinggang, Cheng, Haixia, Wang, Xiaoxu, Cheng, Jie, Jiang, Guoxia, Zhang, Fenglian, Zhang, Zhongshen, and Hao, Zhengping
- Subjects
- *
SILVER catalysts , *EPOXIDATION , *ETHYLENE , *ACTIVATION energy , *HETEROGENEOUS catalysis , *HETEROGENEOUS catalysts , *SILVER - Abstract
Metal‐modified catalysts have attracted extraordinary research attention in heterogeneous catalysis due to their enhanced geometric and electronic structures and outstanding catalytic performances. Silver (Ag) possesses necessary active sites for ethylene epoxidation, but the catalyst activity is usually sacrificed to obtain high selectivity towards ethylene oxide (EO). Herein, we report that using Al can help in tailoring the unoccupied 3d state of Ag on the MnO2 support through strong electronic metal‐support interactions (EMSIs), overcoming the activity‐selectivity trade‐off for ethylene epoxidation and resulting in a very high ethylene conversion rate (~100 %) with 90 % selectivity for EO under mild conditions (170 °C and atmospheric pressure). Structural characterization and theoretical calculations revealed that the EMSIs obtained by the Al modification tailor the unoccupied 3d state of Ag, modulating the adsorption of ethylene (C2H4) and oxygen (O2) and facilitating EO desorption, resulting in high C2H4 conversion. Meanwhile, the increased number of positively charge Ag+ lowers the energy barrier for C2H4(ads) oxidation to produce oxametallacycle (OMC), inducing the unexpectedly high EO selectivity. Such an extraordinary electronic promotion provides new promising pathways for designing advanced metal catalysts with high activity and selectivity in selective oxidation reactions. [ABSTRACT FROM AUTHOR] more...
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- 2024
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29. Ruthenium(II)-Catalyzed Selective C–H Bond Activation of Biindoles and Coupling with Sulfoxonium: An Efficient Access to Pyrido[1,2- a :4,3- b ′]diindole frameworks.
- Author
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Jatoth, Ramanna, Gugulothu, Kishan, Valappil, Rasika Meloth, Nelson, Nithya, and Kumar, K. Shiva
- Subjects
- *
RUTHENIUM catalysts , *ANNULATION , *YLIDES , *RUTHENIUM , *SILVER catalysts , *CYCLIC compounds , *PHYSICAL sciences , *BONDS (Finance) - Abstract
This article presents a study on the synthesis of pyrido[1,2-a:4,3-b']diindoles through a ruthenium-catalyzed coupling/cyclization reaction. The researchers investigated the reaction conditions and found that electron-donating groups and certain substitutions on the indole ring were well tolerated, resulting in good yields of the desired products. The proposed reaction pathway involves the formation of a ruthenacycle intermediate, followed by the insertion of a sulfur ylide and subsequent cyclization. The authors suggest that these pyrido[1,2-a:4,3-b']diindole derivatives may have potential pharmaceutical applications. [Extracted from the article] more...
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- 2024
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30. Silver‐Catalyzed Decarboxylative Acylfluorination of Two Alkenes with Ketonic Acids.
- Author
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Liu, Ren‐Xiang, Wang, Wei, and Yang, Luo
- Subjects
- *
KETONIC acids , *ALKENES , *SILVER catalysts , *BENZYL compounds , *CARBOXYLIC acids , *RADICALS (Chemistry) , *BORONIC acids - Abstract
An acylative fluorination of two different alkenes is developed, assisted by the interaction of silver catalyst and Selectflour. Various α‐ketonic acids can be decarboxylated to form acyl radicals at 35 °C, sequentially add to the electron‐deficient and electron‐ rich alkenes to provide the benzyl fluorinated compounds containing diversified functional groups. [ABSTRACT FROM AUTHOR] more...
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- 2024
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31. Mesoporous Silica Gel Doped with Dysprosium, Lanthanum and Modified with Silver as a Catalyst for Selective Hydrogenation of a 1-Heptyne/1-Heptene Mixture.
- Author
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Tokranov, A. A., Tokranova, E. O., Shafigulin, R. V., Pavlova, L. V., Platonov, I. A., and Bulanova, A. V.
- Subjects
- *
SILICA gel , *SILVER catalysts , *MESOPOROUS silica , *INDUCTIVELY coupled plasma mass spectrometry , *LANTHANUM , *DYSPROSIUM - Abstract
Mesoporous silica gel doped with dysprosium, lanthanum and modified with silver (Dy-Ag/MPS, La-Ag/MPS) was obtained by the template method. The physicochemical characteristics of the obtained catalyst were studied by scanning electron microscopy, X-ray fluorescence and X-ray diffraction analysis, inductively coupled plasma mass spectrometry and temperature-programmed reduction. In addition, the possibility of using obtained materials as an efficient and selective catalysts in the hydrogenation of a 1-heptyne/1-heptene mixture (with 30% of alkyne content) in a temperature range of 140–160 °C and a hydrogen pressure of 3 atm was studied. It was found that after 15 min from the start of the hydrogenation reaction at 140 °C on the La-Ag/MPS catalyst, total conversion of 1-heptyne was observed and selectivity for 1-heptene was 84%. Moreover, it was shown that on a Dy-Ag/MPS at 150 °C 1-heptyne conversion was 84%, the selectivity for alkene was 79%. Furthermore, with an increase in temperature to 160 °C, the conversion of 1-heptyne reaches 95%, the selectivity for 1-heptene—84%. [ABSTRACT FROM AUTHOR] more...
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- 2024
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32. Silver‐Catalyzed Dearomative Skeletal Editing of Indazoles by Donor Carbene Insertion.
- Author
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Li, Linxuan, Chen, Hongzhu, Liu, Menglin, Zhu, Qingwen, Zhang, Hongru, de Ruiter, Graham, and Bi, Xihe
- Subjects
- *
INDAZOLES , *SILVER catalysts , *SCISSION (Chemistry) , *FUNCTIONAL groups , *EDITING , *CARBENES , *SILVER - Abstract
Given the prevalence of heterocyclic scaffolds in drug‐related molecules, converting these highly modular heterocyclic scaffolds into structural diversified and dearomatized analogs is an ideal strategy for improving their physicochemical and pharmacokinetic properties. Here, we described an efficient method for silver carbene‐mediated dearomative N−N bond cleavage leading to skeletal hopping between indazole and 1,2‐dihydroquinazoline via a highly selective single‐carbon insertion procedure. Using this methodology, a series of dihydroquinazoline analogues with diarylmethylene‐substituted quaternary carbon centers were constructed with excellent yields and good functional group compatibility, which was further illustrated by the late‐stage diversification of important pharmaceutically active ingredients. DFT calculations indicated that the silver catalyst not only induces the formation of the silver carbene, but also activates the diazahexatriene intermediate, which plays a crucial role in the formation of the C−N bond. [ABSTRACT FROM AUTHOR] more...
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- 2024
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33. Molecular Dynamic Simulations of Aqueous Micellar Organometallic Catalysis: Methane Functionalization as a Case Study.
- Author
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Matamoros‐Recio, Alejandra, Alonso‐Rueda, Elia, Borrego, Elena, Caballero, Ana, Pérez, Pedro J., and Martín‐Santamaría, Sonsoles
- Subjects
- *
MICELLAR catalysis , *DYNAMIC simulation , *CHEMICAL systems , *PERFLUOROOCTANE sulfonate , *MICELLAR solutions , *CATALYST poisoning , *SILVER catalysts , *METHANE as fuel , *SULFONATES - Abstract
Molecular Dynamics (MD) simulations constitute a powerful tool that provides a 3D perspective of the dynamical behavior of chemical systems. Herein the first MD study of the dynamics of a catalytic organometallic system, in micellar media, is presented. The challenging methane catalytic functionalization into ethyl propionate through a silver‐catalyzed process has been targeted as the case study. The intimate nature of the micelles formed with the surfactants sodium dodecylsulfate (SDS) and potassium perfluorooctane sulfonate (PFOS) has been ascertained, as well as the relative distribution of the main actors in this transformation, namely methane, the diazo reagent and the silver catalyst, the latter in two different forms: the initial compound and a silver‐carbene intermediate. Catalyst deactivation occurs with halide containing surfactants dodecyltrimethylammonium chloride (DTAC) and Triton X‐100. Computed simulations allow explaining the experimental results, indicating that micelles behave differently regarding the degree of accumulation and the local distribution of the reactants and their effect in the molecular collisions leading to net reaction. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
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34. Photocatalytic degradation of 2,4-dichlorophenol using nanomaterials silver halide catalysts.
- Author
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Moja, Mahlako Mary, Mapossa, António Benjamim, Chirwa, Evans Martin Nkhalambayausi, and Tichapondwa, Shepherd
- Subjects
SILVER halides ,CHLOROPHENOLS ,PHOTOCATALYSTS ,PRECIPITATION (Chemistry) ,VISIBLE spectra ,PHOTODEGRADATION ,NANOSTRUCTURED materials ,SILVER catalysts - Abstract
In this study, the photocatalytic activity of nanomaterials Ag/AgX (X = Cl, Br, I) is reported. Highly efficient silver halide (Ag/AgX where X = Cl, Br, I) photocatalysts were synthesized through a hydrothermal method. The samples were characterized using a range of techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) to check their structural, morphology, textural and optical properties. In addition, the photocatalytic activity of photocatalysts was evaluated through the degradation of 2,4-dichlorophenol (2,4-DCP) under UV and visible light irradiation. XRD analysis confirmed the presence of a single-phase structure (pure phase) in the synthesized photocatalysts. SEM micrographs showed agglomeration with a non-uniform distribution of particles, which is a characteristic of surfactant-free precipitation reactions in aqueous media. The Ag/AgBr photocatalyst exhibited the best degradation efficiency, resulting in 83.37% and 89.39% photodegradation after 5 h of UV and visible light irradiation, respectively. The effect of catalyst loading, initial solution pH, and 2,4-DCP concentration was investigated for the best-performing Ag/AgBr photocatalyst. The degradation kinetics were best described by the pseudo-first-order Langmuir–Hinshelwood model. The photocatalytic capacity of Ag/AgBr decreased by 50% after five reuse cycles. SEM images revealed heightened levels of photodegradation on the catalyst surface. The study proved the feasibility of using simple synthesis methods to produce visible light active photocatalysts capable of degrading refractory phenolic pollutants in aqueous systems. [ABSTRACT FROM AUTHOR] more...
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- 2024
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35. Modification of SmMn 2 O 5 Catalyst with Silver for Soot Oxidation: Ag Loading and Metal–Support Interactions.
- Author
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Jin, Baofang, Liu, Yuxin, Ma, Yue, Li, Zhenguo, Li, Kaixiang, Liu, Shuang, Ran, Rui, and Wu, Xiaodong
- Subjects
- *
SILVER catalysts , *SOOT , *METHANATION , *X-ray photoelectron spectroscopy , *X-ray powder diffraction , *TRANSMISSION electron microscopy - Abstract
A series of Ag-modified manganese-mullite (SmMn2O5) catalysts with different Ag contents (1, 3, and 6 wt.%) were prepared via a citric acid sol–gel method for catalytic soot oxidation. The catalysts were characterized by powder X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Raman spectroscopy, transmission electron microscopy (TEM), high-resolution transmission electron microscopy analysis (HRTEM), X-ray photoelectron spectroscopy (XPS), and H2 temperature-programmed reduction (H2-TPR). The soot oxidation activity of the mullite was significantly promoted by the addition of silver and affected by the loading amount of the metal. Herein, the influences of silver loading on the metal size distribution and its interactions with the mullite were studied. Based on these characterizations, a possible soot oxidation reaction mechanism was proposed for silver-modified SmMn2O5. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
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36. Silver(I)-catalyzed stereoselective Meyer–Schuster-type rearrangement: synthesis of densely substituted α-iodo α,β-unsaturated thioesters.
- Author
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Lopes, José L., Baldassari, Lucas L., and Lüdtke, Diogo S.
- Subjects
- *
THIOESTERS , *SILVER catalysts , *SILVER sulfide , *SILVER , *IODINE , *ALKENES , *CATALYSTS - Abstract
Herein, we report our approach for a Meyer–Schuster type rearrangement to access α-iodo α,β-unsaturated thioesters from propargyl thioalkynes using a silver(I) catalyst and N-iodosuccinimide as an electrophilic iodine source. The reaction proceeds smoothly for a range of propargyl thioalkynes, thus delivering tri- and tetrasubstituted olefins in good yields and, for a number of examples, (Z)-selectivity. The silver catalyst presumably plays a dual role involving both the activation of the π-system by the alkynophilic Ag(I) and the activation of the NIS, ultimately leading to a sulfur-stabilized vinyl cation/ketenethionium intermediate. This reactive intermediate is trapped intramolecularly to yield an oxetane, which then readily undergoes decomposition to deliver the final product. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
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37. Enhanced CO oxidation performance over hierarchical flower-like Co3O4 based nanosheets via optimizing oxygen activation and CO chemisorption.
- Author
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Wang, Xinyang, Li, Rui, Luo, Xinyu, Mu, Jincheng, Peng, Jianbiao, Yan, Guangxuan, Wei, Pengkun, Tian, Zhenbang, Huang, Zuohua, and Cao, Zhiguo
- Subjects
- *
OXIDATION of carbon monoxide , *CHEMISORPTION , *SILVER catalysts , *CATALYTIC oxidation , *NANOSTRUCTURED materials , *CHARGE exchange - Abstract
The interfacial interaction between AgCoO 2 and Co 3 O 4 enhanced CO conversion to CO 2 but not inert carbonates, by optimizing oxygen activation and CO chemisorption. [Display omitted] • The doped silver species highly dispersed in the form of AgCoO 2 in Co 3 O 4 based catalysts. • The interfacial interaction and electron transfer optimized CO chemisorption strength and oxygen activation. • The chemisorbed CO is preferentially converted to CO 2 but not inert carbonates on Ag 0.02 Co. • The silver doped catalysts exhibited superior CO oxidation activity and 6.3-fold higher reaction rate. Enhancing low-temperature activity is a focus for carbon monoxide (CO) elimination by catalytic oxidation. In this work, the hierarchical flower-like silver (Ag) modified cobalt oxides (Co 3 O 4) nanosheets were prepared by solvothermal method and applied into catalytic CO oxidation. The doped Ag species in the form of AgCoO 2 induced the prolongated surface Co–O bond and weaker bond intensity. Consequently, the oxygen activation/migration ability and redox capacity of Ag 0.02 Co were enhanced with more oxygen vacancies. The chemisorbed CO was preferentially converted to CO 2 but not carbonates. The inhibited carbonates accumulation could avoid the coverage of active sites. According to Density functional theory (DFT) calculations, the electron transfer from AgCoO 2 to Co 3 O 4 promote electron donation ability of Co 3 O 4 layer, benefiting for oxygen activation. Moreover, the longer Co–C and C–O bond length suggest the weakened chemisorption strength and higher active of CO molecule. The Ag modified Co 3 O 4 exhibited more satisfactory activity at lower temperature. Typically, it realized 100% CO conversion at 90 °C, and displayed 6.3-fold higher reaction rate than pristine Co 3 O 4 at 40 °C. Moreover, the Ag 0.02 Co exhibited outstanding long-term stability and water resistance. In summary, the optimized oxygen activation, CO chemisorption and interfacial electron transfer synergistically boosted the CO oxidation activity on Ag modified Co 3 O 4. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
38. Ethylene polymerization using N-Heterocyclic carbene complexes of silver and aluminum.
- Author
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Kimura, Nanako, Takeuchi, Daisuke, Ogura, Sayoko, Takazawa, Ayaka, Kakiage, Masaki, Yamanobe, Takeshi, and Uehara, Hiroki
- Subjects
- *
TRANSITION metal catalysts , *POLYMERIZATION , *ETHYLENE , *SILVER catalysts , *ALUMINUM , *MELTING points , *RING-opening polymerization , *SILVER - Abstract
Various transition metal catalysts have been utilized for ethylene polymerization. Silver catalysts have attracted less attention as the catalysts, but are potential for production of high molecular weight polyethylene. Herein, we report that silver complexes with various N-heterocyclic carbene (NHC) ligands in combination with modified methylaluminoxane (MMAO) afford polyethylene with high molecular weight (melting point over 140°C). SEM observation showed that the produced polyethylene has ultra-high molecular weight. NMR investigation of the reaction between the silver complexes with organoaluminums indicate that the NHC ligands transfer from the silver complex to aluminum to produce NHC aluminum complexes. Ph3C[B(C6F5)4] abstract methyl group from the NHC aluminum complex to afford cationic aluminum complex. The NHC aluminum complex promoted ethylene polymerization in the presence of Ph3C[B(C6F5)4] and organoaluminums. NHC ligand also promoted ethylene polymerization in combination with MMAO to produce polyethylene with high melting point (140.7°C). Thus, the aluminum complexes are considered to be the actual active species in silver-catalyzed ethylene polymerization. [ABSTRACT FROM AUTHOR] more...
- Published
- 2023
- Full Text
- View/download PDF
39. Dipolarophile‐Steered Formal Stereodivergent Synthesis of 2,5‐cis/trans‐Pyrrolidines Based on Asymmetric 1,3‐Dipolar Cycloaddition of Imino Lactones.
- Author
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Furuya, Shohei, Muroi, Kenji, Kanemoto, Kazuya, and Fukuzawa, Shin‐ichi
- Subjects
- *
PYRROLIDINE synthesis , *RING formation (Chemistry) , *CARBONYL compounds , *LACTONES , *ASYMMETRIC synthesis , *ISOXAZOLIDINES , *SILVER catalysts , *DECARBOXYLATION , *ALKENES - Abstract
The stereodivergent asymmetric synthesis of 2,5‐trans/cis pyrrolidines by 1,3‐dipolar cycloaddition using two different types of activated alkenes is described. When ylidene‐isoxazolones were employed as dipolarophiles, the Ag/(S,Sp)‐iPr‐FcPHOX‐catalyzed asymmetric [3+2] cycloaddition of imino lactones proceeded with 2,5‐trans selectivity. Subsequent decarboxylation of the isoxazolone rings produced pyrrolidines with 2,5‐trans stereoretention. In the reaction using acyclic enones as activated alkenes, the Ag/(R,Sp)‐ThioClickFerrophos complex‐catalyzed asymmetric [3+2] cycloaddition afforded 2,5‐cis substituted pyrrolidines in high yields and enantioselectivities. Therefore, these methods can be considered as a formal stereodivergent synthesis of 2,5‐cis/trans pyrrolidines. [ABSTRACT FROM AUTHOR] more...
- Published
- 2023
- Full Text
- View/download PDF
40. The Study of Antioxidant Activity of Silver Nanoparticles by the Method of Luminol-Activated Chemiluminescence in the H2O2–Horseradish Peroxidase System.
- Author
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Zvereva, M. V., Zhmurova, A. V., and Sapozhnikov, A. N.
- Subjects
- *
SILVER nanoparticles , *HORSERADISH peroxidase , *CHEMILUMINESCENCE , *PEROXIDASE , *ARABINOGALACTAN , *ANTIOXIDANTS , *SILVER catalysts - Abstract
The work presents the results of the synthesis and characterization of arabinogalactan-stabilized Ag0NPs nanoparticles, and also the assessment of their radical-binding ability by the luminol-activated chemiluminescence method using the radical-generating horseradish peroxidase–H2O2 system. The obtained water-soluble nanocomposites containing 0.5–5.0% of the inorganic phase are formed as nanoparticles of zero-valent silver stabilized by arabinogalactan macromolecules. The shape of the nanoparticles is close to spherical, and the average size varies in the range of 3.0–5.4 nm. Using the method of activated chemiluminescence and the protocol for processing the obtained TAR values, it was shown for the first time that aqueous solutions of the resulting nanocomposites have antiradical activity with a pronounced concentration-dependent nature. [ABSTRACT FROM AUTHOR] more...
- Published
- 2023
- Full Text
- View/download PDF
41. Catalytic Activity and Stability of Oxygen Reduction Catalysts Based on Silver and Nickel in Alkali-Ethanol Media.
- Author
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Tarantseva, K. R., Tarantsev, K. V., and Korosteleva, A. V.
- Subjects
- *
CATALYTIC activity , *SILVER catalysts , *OXYGEN reduction , *FOAM , *NICKEL , *NICKEL catalysts , *COPPER , *ELECTROLYTIC oxidation - Abstract
Catalytic activity and stability of silver and nickel catalysts deposited on various copper substrates for oxygen reduction in ethanol-alkaline media EtOH + KOH + H2O (pH = 13.1), previously proposed for low-temperature electro-oxidation of ethanol, are studied. It is established that the original silver catalytic activity towards oxygen reduction is high, although chemical instability of silver in alkaline media limits the possibility of using it for low-temperature oxidation of ethanol within strongly alkaline ethanolic media. Under these conditions, catalysts based upon nickel foam are more stable, which makes them more promising for practical use, despite the lower oxygen reduction currents. [ABSTRACT FROM AUTHOR] more...
- Published
- 2023
- Full Text
- View/download PDF
42. Silver Catalysts Supported on High Surface Area α‐Alumina: Effect of Carbohydrate Template Size and Heat Treatment on Phase Purity.
- Author
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Keijzer, Claudia J., Dalebout, Remco, de Rijk, Jan Willem, Lockemeyer, John R., Lohr, Tracy L., van den Brink, Peter, and de Jongh, Petra E.
- Subjects
- *
SILVER catalysts , *CATALYST supports , *SURFACE area , *HEAT treatment , *ETHYLENE oxide , *OXIDE ceramics , *POLYMETHYLMETHACRYLATE , *METALLOCENE catalysts - Abstract
α‐Alumina is a non‐porous metal oxide with applications in ceramics and catalysis. Introducing pores into this material to create catalytically relevant surface area is challenging due to phase transitions over a wide temperature range. Current synthesis strategies involve hard templates such as synthetic polymers, e. g. polymethylmethacrylate (PMMA). Here, we compare cellulose and carbonized glucose as low‐cost and natural alternative templates for high surface area α‐alumina with a two‐step heating method. Quantitative XRD was used to methodically investigate alumina phase purity. Increasing the template size in the range of 220–1000 nm improved α‐alumina purity from 75 to 98 %, while maintaining high surface areas (21–29 m2 g−1). Phase purity increases substantially by prolonging the calcination time. The synthesized high surface area α‐alumina was studied as support for silver catalysts in the epoxidation of ethylene and allowed high silver loadings. Ethylene oxide selectivity increased with enhanced α‐alumina phase purity. Our 30 wt % silver catalyst on pure high surface area α‐alumina did not show loss in selectivity compared to a 15 wt % silver catalyst on commercial non‐porous α‐alumina. This shows the potential of carbohydrate templates, the importance of templating parameters and the benefits of pure high surface area α‐alumina as support for silver catalysts. [ABSTRACT FROM AUTHOR] more...
- Published
- 2023
- Full Text
- View/download PDF
43. Study on hydrogen peroxide synergistic nitric acid leaching of silver in a failed silver catalyst.
- Author
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YANG Quan, CHEN Mingjun, HAN Jibiao, HU Jianjun, YAO Yiqin, YAO Yanbo, FU Hao, and LI Yong
- Subjects
SILVER nitrate ,SILVER catalysts ,NITROGEN oxides ,HYDROGEN peroxide ,NITRIC acid ,LEACHING - Abstract
The effect of hydrogen peroxide leaching of silver was studied on the basis of traditional nitric acid leaching of silver from spent silver catalysts. The silver leaching rate was 99.76% by slowly adding hydrogen peroxide in the conditions of 2 mol/L HNO
3 , leaching temperature 70 °C, leaching time 120 minutes, and solid-liquid ratio 1:4, which had good leaching effect. Hydrogen peroxide oxidizes Ag to Ag2 O, which can effectively improve the leaching rate of silver, while the nitrogen oxide produced by the reaction between nitric acid and silver is oxidized by H2 O2 to generate nitric acid and continue to participate the reaction. The use of nitric acid hydrogen peroxide as a leaching agent ensures efficient silver leaching, reduces the emission of nitrogen oxides, and provides a theoretical basis and technical support for the green and efficient recovery of spent silver catalysts. [ABSTRACT FROM AUTHOR] more...- Published
- 2023
44. Going Beyond Silver in Ethylene Epoxidation with First‐Principles Catalyst Screening.
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Huš, Matej, Grilc, Miha, Teržan, Janvit, Gyergyek, Sašo, Likozar, Blaž, and Hellman, Anders
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- *
SILVER catalysts , *EPOXIDATION , *AB-initio calculations , *ETHYLENE , *CATALYSTS , *SILVER - Abstract
Ethylene epoxidation is industrially and commercially one of the most important selective oxidations. Silver catalysts have been state‐of‐the‐art for decades, their efficiency steadily improving with empirical discoveries of dopants and co‐catalysts. Herein, we perform a computational screening of the metals in the periodic table, identify prospective superior catalysts and experimentally demonstrate that Ag/CuPb, Ag/CuCd and Ag/CuTl outperform the pure‐Ag catalysts, while they still confer an easily scalable synthesis protocol. Furthermore, we show that to harness the potential of computationally‐led discovery of catalysts fully, it is essential to include the relevant in situ conditions e.g., surface oxidation, parasitic side reactions and ethylene epoxide decomposition, as neglecting such effects leads to erroneous predictions. We combine ab initio calculations, scaling relations, and rigorous reactor microkinetic modelling, which goes beyond conventional simplified steady‐state or rate‐determining modelling on immutable catalyst surfaces. The modelling insights have enabled us to both synthesise novel catalysts and theoretically understand experimental findings, thus, bridging the gap between first‐principles simulations and industrial applications. We show that the computational catalyst design can be easily extended to include larger reaction networks and other effects, such as surface oxidations. The feasibility was confirmed by experimental agreement. [ABSTRACT FROM AUTHOR] more...
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- 2023
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45. Au和Ag修饰TNTAs阵列及光电催化甘油转化研究.
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王旭东, 王剑, 田入峰, 张王刚, 刘一鸣, and 李晓红
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TITANIUM dioxide , *NANOTUBES , *PHOTOELECTROCHEMISTRY , *SILVER catalysts , *HYDROGEN production , *GLYCERIN , *SURFACE plasmon resonance - Abstract
TiO2 nanotube arrays (TNTAs) were prepared by anodic oxidation with a tube diameter of 60 nm and a tube length of 5.4/im. Further Au- and Ag-modified TNT As/Au and TNT As/Ag nanotube arrays were prepared by electrodeposition. The effects of loading with different Au and Ag contents on the photoanodic photo-electrocatalytic conversion of glycerol-coupled hydrogen production coupling were evaluated. The results showed that TNT As loaded with Au and Ag could photo catalytically convert glycerol into high value-added products such as glyceraldehyde (GLI)) and dihydroxy ace tone (T)H A) and produce hyd rogen synergistically. TNT As/Au (0.08 m mol/L) and TNT As/Ag (0.04 mM) showed the highest catalytic performance with hydrogen production rates of 213.8/imol/cm²/h and 198.1/imol/cm1/h, glycerol conversion of 4.6 % and 4.4%, and T)H A selectivity of 15.4% and 15.3%, respectively. The best performance of the samples was attributed to the plasmon resonance effect of the metal nanoparticles, i.e., the metal acted as an electron trap to effectively gather the photoexcited electrons, and the electrons in the TiO2 conduction band were transferred to the metal to prevent the compounding of photogenerated electron-hole pairs, which effectively improved the catalytic performance of the TiO2 nanotube arrays. [ABSTRACT FROM AUTHOR] more...
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- 2023
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46. Alumina-Supported Silver Catalyst for O3-Assisted Catalytic Abatement of CO: Effect of Ag Loading.
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Mytareva, Alina I., Kanaev, Sergey A., Bokarev, Dmitriy A., Kazakov, Alexander V., Baeva, Galina N., and Stakheev, Alexander Yu.
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- *
SILVER catalysts , *SILVER , *CHEMICAL decomposition , *CATALYTIC oxidation , *REACTIVE oxygen species , *ULTRAVIOLET-visible spectroscopy , *WATER gas shift reactions , *AGGLOMERATION (Materials) - Abstract
A series of Ag/Al2O3 catalysts with different Ag loading in a range of 0.5–10 wt% was synthesized by incipient wetness impregnation. The obtained catalysts were characterized by XRD, SEM-EDX, TEM and UV-Visible spectroscopy. It was shown that at low Ag loading (0.5 and 1 wt% Ag) an isolated Ag+ species predominate on the alumina surface. The formation of Agn clusters begins as Ag content was increased to 3 wt% Ag. Higher Ag loading (10 wt%) causes an agglomeration of Agn clusters and formation of relatively large Ag nanoparticles (AgNPs). The catalytic performance of the Ag/Al2O3 catalysts was studied in the conventional (with O2) and O3-assisted catalytic CO oxidation (with O3) and O3 decomposition reactions within the temperature range of 25–350 °C. Analysis of the data obtained allows concluding that conventional CO oxidation proceeds mainly over Agn clusters, while for O3-assited CO oxidation Ag+ species are also necessary. The Ag+ species promote the ozone decomposition and, as a consequence, the formation of highly reactive atomic oxygen species, which are favorable for low-temperature CO activation. The contribution of large metal species (large Agn clusters and AgNPs) to the overall catalytic performance appears to be less pronounced. [ABSTRACT FROM AUTHOR] more...
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- 2023
- Full Text
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47. Solid-State Silver-Catalyzed Ring-Opening Fluorination of Cyclobutanols by Using Mechanochemistry.
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Isshiki, Ryota, Kubota, Koji, and Ito, Hajime
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FLUORINATION , *MECHANICAL chemistry , *ORGANIC chemistry , *SCISSION (Chemistry) , *SILVER catalysts , *CYCLIC compounds , *RING-opening reactions - Abstract
Although the benefits of mechanochemistry for solid-state reactions of compounds with reactive bonds, such as organic halides, have been well demonstrated, nonactivated bond cleavage through mechanochemical transformation remains unexplored. Keywords: C-C bond cleavage; fluorination; mechanochemistry; ball-milling; solid-state chemistry; silver catalysis EN C-C bond cleavage fluorination mechanochemistry ball-milling solid-state chemistry silver catalysis 1419 1424 6 07/11/23 20230725 NES 230725 Graph In recent years, solvent-free solid-state organic transformations using ball-milling, known as mechanochemical reactions, have been extensively studied as new tools for organic chemistry. C-C bond cleavage, fluorination, mechanochemistry, ball-milling, silver catalysis, solid-state chemistry. [Extracted from the article] more...
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- 2023
- Full Text
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48. Hydroxypillar[5]arene‐Confined Silver Nanocatalyst for Selective Electrochemical Reduction of CO2 to Ethanol.
- Author
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Qin, Junjie, Wang, Tao, Zhai, Mingming, Wu, Chengyu, Liu, Yahu A., Yang, Bo, Yang, Hui, Wen, Ke, and Hu, Weibo
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- *
ELECTROLYTIC reduction , *NANOPARTICLES , *SILVER catalysts , *ETHANOL , *DENSITY functional theory , *COUPLING reactions (Chemistry) , *SILVER - Abstract
CO is usually the dominant product on silver‐based catalysts in electrochemical CO2 reduction reaction (CO2RR) possibly due to weak *CO adsorption. In this report, a hydroxypillar[5]arene‐extended porous polymer‐confined silver catalyst (PAF‐PA5‐Ag‐0.8) for electrochemical CO2RR which can selectively produce ethanol with a maximum Faradaic efficiency of 55% at 11 mA cm−1 is described. The study reveals that the hydroxypillar[5]arene‐confined Ag clusters are the active sites for ethanol formation. Moreover, temperature‐programmed desorption measurements demonstrate an enhanced adsorption strength of CO* on PAF‐PA5‐Ag‐0.8 compared with that on commercial Ag nanoparticles, which is favored by the C‐C coupling to form ethanol. The density functional theory study indicates that the confined Ag clusters in PAF‐PA5‐Ag‐0.8 contribute to high C2 selectivity in CO2RR through facilitating *COOH formation, stabilizing *CO intermediates, and inhibiting hydrogen evolution. This work provides a new design strategy by modulating *CO adsorption strength on non‐copper electrocatalysts in converting CO2 into "green" C2 products. [ABSTRACT FROM AUTHOR] more...
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- 2023
- Full Text
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49. Silver-Catalyzed Decarboxylative Acylation of Isocyanides Accesses to α-Ketoamides with Air as a Sole Oxidant.
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Xu, Jia, Li, Xue, Chen, Xing-Yu, He, Yu-Ting, Lei, Jie, Chen, Zhong-Zhu, and Xu, Zhi-Gang
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- *
ISOCYANIDES , *ACYLATION , *OXIDIZING agents , *SILVER catalysts , *FUNCTIONAL groups - Abstract
α-Ketoamide moieties, as privileged units, may represent a valuable option to develop compounds with favorable biological activities, such as low toxicity, promising PK and drug-like properties. An efficient silver-catalyzed decarboxylative acylation of α-oxocarboxylic acids with isocyanides was developed to derivatize the α-ketoamide functional group via a multicomponent reaction (MCR) cascade sequence in one pot. A series of α-ketoamides was synthesized with three components of isocyanides, aromatic α-oxocarboxylic acid analogues and water in moderate yields. Based on the research, the silver-catalyzed decarboxylative acylation confirmed that an oxygen atom of the amide moiety was derived from the water and air as a sole oxidant for the whole process. [ABSTRACT FROM AUTHOR] more...
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- 2023
- Full Text
- View/download PDF
50. Nanoscale Management of CO Transport in CO2 Electroreduction: Boosting Faradaic Efficiency to Multicarbon Products via Nanostructured Tandem Electrocatalysts.
- Author
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Wei, Chaolong, Yang, Yuehua, Ma, Haibin, Sun, Guangxin, Wang, Xin, Cheng, Yaqi, Zhang, Caiwei, Yeo, Boon Siang, He, Chunnian, and Wong, Andrew Barnabas
- Subjects
- *
ELECTROCATALYSTS , *SILVER catalysts , *ELECTROLYTIC reduction , *RAMAN spectroscopy , *FINITE element method , *SILVER nanoparticles , *CARBON dioxide reduction - Abstract
Tandem catalysis presents a promising strategy to improve the selectivity toward multicarbon products in the electrocatalytic carbon dioxide reduction reaction (CO2RR). For CO2RR, CO is a critical intermediate for producing multicarbon products. However, the management of CO localization and CO diffusion remains underexplored despite its critical role. Herein, a 3D tandem catalyst electrode with silver nanoparticles (Ag NPs) is designed to generate CO as an intermediate product within a copper (Cu) nanoneedle array. Via this nanostructured design, CO2 forms C2+ products with a high Faradaic efficiency (FEC2+) of 64% in an H‐cell and 70% in a flow cell with a current density of 350 mA cm−2. These figures‐of‐merit are currently among the top literature reports. More importantly, in situ Raman spectroscopy and finite‐element method calculations are employed to elucidate the origins of enhanced selectivity. These approaches reveal the crucial role of prolonging the CO diffusion path length for improving CO utilization during CO2 conversion with tandem catalyst systems. The favorable CO2RR FEC2+ in two distinct environments (H‐cell and flow cell) further corroborates that this effect is not limited to a particular reactor environment. Overall, this study provides new insights for designing tandem catalysts for improved CO2RR selectivity to C2+ products. [ABSTRACT FROM AUTHOR] more...
- Published
- 2023
- Full Text
- View/download PDF
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