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Palladium-catalyzed base-and solvent-controlled chemoselective allylation of amino acids with allylic carbonates

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Chinese chemical Letters 2022年第11期33卷 4850-4855页

作者： Yang Zhou Hang Chen Panpan Lei Chunming Gui Haifeng Wang Qiongjiao Yan Wei Wang Fener Chen Pharmaceutical Research Institute Wuhan Institute of TechnologyWuhan 430205China Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province China West Normal UniversityNanchong 637009China Engineering Center of Catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Catalysis for Chiral Drugs Shanghai 200433China

The utilization of readily available amino acids,which is not only an oxygen nucleophile but also a nitrogen nucleophile,in palladium-catalyzed allylic substitution is realized under mild *** chemoselectivity and multiple allylation are controlled by adjusting the reaction *** represents the first example of this convenient access to valuable N,O-diallylated amino *** the title conditions,a range of amino acids(α-,β-,γ-)and dipeptides can be readily converted in to the corresponding allylic products with excellent yields(67 examples,up to 99%yield)as well as good functional group tolerance.

关键词： Allylation Amino acid Carbonates Chemoselectivity Palladium

Solubility and selectivity behavior of methane and hydrogen in several solvents at 313.15 K

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Journal of Molecular Liquids 2025年 427卷

作者： Son, Juhee Verma, Sweety Kang, Jo Hong Park, Hyun Sic Song, Hojun Bae, Youn-Sang Low-Carbon Energy Group Korea Institute of Industrial Technology 55 Jongga-ro Jung-gu Ulsan44413 Korea Republic of Department of Chemical and Biomolecular Engineering Yonsei University 50 Yonsei-ro Seodaemun-gu Seoul03722 Korea Republic of Chemical Process Solution Research Center Korea Research Institute of Chemical Technology Daejeon34114 Korea Republic of

The turquoise hydrogen process, which involves the decomposition of methane (CH4) into hydrogen (H2) and carbon black, necessitates the effective separation of unreacted methane from the produced gas to ensure high-purity hydrogen. This study investigates the efficacy of various solvents such as ethanol, n-hexane, oleic acid, ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate), cyclohexane, ethylene glycol, and 1,4-dioxane in the absorption of CH4 and H2 for purification. Absorption experiments were conducted using 50 mL of each pure solvent at 313.15 K, and the solubility of CH4 and H2 was analyzed on both molar and mass basis. Oleic acid exhibited the highest absorption capacity for both gases on a molar basis. In contrast, n-hexane and cyclohexane demonstrated the highest selectivity for CH4 over H2. The selectivity of CH4/H2 decreased with the higher partial pressure and smaller molecular size of H2, which makes it easier to occupy free volume in the solvent than CH4. Additionally, solvents containing polar atoms or groups, such as ethylene glycol and 1,4-dioxane with oxygen (O) or hydroxyl group (–OH), impeded CH4 absorption, decreasing the selectivity. This comprehensive analysis demonstrates the potential of these solvents in optimizing the hydrogen purification process and provides information for the development of more efficient separation techniques. © 2025 Elsevier B.V.

关键词： Ethylene glycol

Facile Synthesis of Ceo2-Decorated Co4n Nanoparticles as a Highly Active and Durable Electrocatalyst for the Oxygen Evolution Reaction

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SSRN 2023年

作者： Min, Kyeongseok Kim, Minjung Min, Sojeong Kim, Hyejin Baeck, Sung-Hyeon Department of Chemistry and Chemical Engineering Education and Research Center for Smart Energy Materials and Process Inha University Incheon22212 Korea Republic of

For the production of high-purity hydrogen via water electrolysis, efficient catalysts must be developed for the electrochemical oxygen evolution reaction (OER). In this study, Co- and Ce-based bimetal organic frameworks are employed as self-templates for the synthesis of CeO2-decorated Co4N (Co4N/CeO2) nanoparticles with strongly coupled heterointerfaces. The rough surface and well-developed mesoporous structure of Co4N/CeO2 can enhance the exposure of electrochemically active sites. In addition, the lattice mismatch at the heterointerface between Co4N and CeO2 introduces abundant oxygen vacancies, which moderately controls the electronic structure and provides efficient active sites for an alkaline OER. Consequently, the as-prepared Co4N/CeO2 electrocatalyst exhibits superior OER activity: a small overpotential of 297 mV to acquire a current density of 10 mA cm−2, low Tafel slope of 88 mV dec−1, and a turnover frequency of 4.75 s−1 at an overpotential of 420 mV. Additionally, the Co4N/CeO2 nanoparticles show an excellent long-term durability of more than 80 h of continuous electrocatalytic operation in an alkaline solution. This study highlights the facile preparation of non-noble-metal-based electrocatalysts for energy conversion and storage technologies. © 2023, The Authors. All rights reserved.

关键词： Cerium oxide

Understanding electrokinetic thermodynamics in nanochannels

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Chinese Journal of chemical engineering 2021年第3期34卷 33-41页

作者： Jianglong Du Haolan Tao Jie Yang Cheng Lian Sen Lin Honglai Liu State Key Laboratory of Chemical Engineering Shanghai Engineering Research Center of Hierarchical Nanomaterialsand School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Institute for Theoretical Physics Center for Extreme Matter and Emergent PhenomenaUtrecht UniversityPrincetonplein 53584 CC Utrechtthe Netherlands National Engineering Research Center for Integrated Utilization of Salt Lake Resources and State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical ProcessEast China University of Science and TechnologyShanghai 200237China

Understanding the electrokinetic conversion efficiency in a nanochannel is vital for designing energy storage and conversion *** this paper,an analytical electrokinetic energy conversion efficiency in a nanochannel is obtained based on the linear electrokinetic *** analytical result shows that the conversion efficiency has a maximum with the increasing of the nanochannel pore *** solutions based on the Poisson-Nernst-Planck(PNP)and Navier-Stokes(NS)equations are used to confirm the analytical ***,the influences of the pore radius and surface roughness on the conversion efficiency in nanochannels are also studied by the numerical *** particular,the influences of the surface roughness on the fluid flow,streaming current and streaming potential are *** results show that the large bumps and grooves representing the roughness can hinder the fluid flows and ion transports in the *** maximum efficiency in a smooth nanochannel is higher than that in a rough ***,the small bumps and grooves can increase the surface area of the channel,which is beneficial to improving the conversion efficiency in some *** research can provide theoretical guidance to design electrokinetic energy conversion devices.

关键词： Electrokinetic conversion efficiency Linear electrokinetics Nanostructure Dynamic simulation Thermodynamics

Application of percarbonate and peroxymonocarbonate in decontamination technologies

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Journal of Environmental Sciences 2021年第7期33卷 100-115页

作者： Bo-Tao Zhang Lulu Kuang Yanguo Teng Maohong Fan Yan Ma College of Water Sciences Beijing Normal UniversityBeijing 100875China Engineering Research Center of Groundwater Pollution Control and Remediation Ministry of EducationBeijing 100875China Department of Chemical and Petroleum Engineering University of WyomingLaramieWY 82071United States School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China

Sodium percarbonate(SPC)and peroxymonocarbonate(PMC)have been widely used in modified Fenton reactions because of their multiple superior features,such as a wide pH range and environmental *** broad review is intended to provide the fundamental information,status and progress of SPC and PMC based decontamination technologies according to the peer-reviewed papers in the last two *** SPC and PMC can directly decompose various *** degradation efficiency will be enhanced and the target contaminants will be expanded after the activation of SPC and *** most commonly used catalysts for SPC activation are iron compounds while cobalt composi-tions are applied to activate PMC in homogenous and heterogeneous catalytical *** generation and participation of hydroxyl,superoxide and/or carbonate radicals are involved in the activated SPC and PMC *** reductive radicals,such as carbon dioxide and hydroxyethyl radicals,can be generated when formic acid or methanol is added in the Fe(II)/SPC system,which can reduce target *** can also be activated by energy,tetraacetylethylenediamine,ozone and buffered alkaline to generate different reactive radicals for pollutant *** SPC and activated SPC have been assessed for application in-situ chemical oxidation and sludge dewatering *** challenges and prospects of SPC and PMC based decontamination technologies are also addressed in the last section.

关键词： Sodium percarbonate Peroxymonocarbonate Activation Radical Decontamination technologies

Bimetallic Nickel Iron Sulfide Directly Grown on Defect-Rich Ti3c2 Mxene as an Efficient Bifunctional Electrocatalyst for Water Electrolysis

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SSRN 2023年

作者： Min, Kyeongseok Lee, Geunchang Son, Yujin Seong, Haemin Baeck, Sung-Hyeon Department of Chemistry and Chemical Engineering Education and Research Center for Smart Energy Materials and Process Inha University Incheon22212 Korea Republic of

Water electrolysis has been regarded as ideal method for producing high-purity hydrogen without the generation of environmental pollutants. Accordingly, the development of precious metal-free electrocatalysts that demonstrate high activity for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) is essential for practical water electrolysis. Herein, porosity-engineered Ti3C2 MXene is employed as an efficient substrate for a bimetallic Ni-Fe-S electrocatalyst. The porous and defect-rich Ti3C2 (D-Ti3C2) flakes provide metal-like electrical conductivity and large surface area for direct growth of active species. Simultaneously, the Ni-Fe-S nanoparticles, constructed through a strong coupling between NiS2 and (Ni,Fe)S2 solid solution, not only serve as active sites with rich redox properties, but also generate charge transfer channels for electrochemical reactions. Leveraging these advantageous properties, the resulting Ni-Fe-S/D-Ti3C2 electrocatalyst exhibits excellent bifunctional electrocatalytic performance toward both OER and HER. As a result, the symmetric water electrolysis cell using the Ni-Fe-S/D-Ti3C2 requires a low cell voltage of 1.621 V to deliver current density of 10 mA cm−2, and shows stable electrocatalytic performance over 100 hours of continuous operation. © 2023, The Authors. All rights reserved.

关键词： Porosity

Recent advances in H_(2)O_(2)-based advanced oxidation processes for removal of antibiotics from wastewater

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Chinese chemical Letters 2023年第3期34卷 39-48页

作者： Xuechun Wang Jiana Jing Minghua Zhou Raf Dewil Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationCollege of Environmental Science and EngineeringNankai UniversityTianjin 300350China Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution Nankai UniversityTianjin 300350China Tianjin Advanced Water Treatment Technology International Joint Research Center College of Environmental Science and EngineeringNankai UniversityTianjin 300350China Department of Chemical Engineering KU LeuvenJ.De Nayerlaan 5Sint-Katelijne-Waver B-2860Belgium

As important emerging contaminants, antibiotics have caused potential hazards to the ecological environment and human health due to their extensive production and consumption. Among various techniques for removing antibiotics from wastewater, H_(2)O_(2)-based advanced oxidation processes(AOPs) have received increasing attention due to their fast reaction rate and strong oxidation capability. Hence this review critically discusses:(i) Recent research progress of AOPs with the addition of H_(2)O_(2) for antibiotics removal through different methods of H_(2)O_(2) activation;(ii) recent advances in AOPs that can in-situ generate and activate H_(2)O_(2) for antibiotics removal;(iii) H_(2)O_(2)-based AOPs as a combination with other techniques for the degradation and mineralization of antibiotics in wastewater. Future perspectives about H_(2)O_(2)-based AOPs are also presented to grasp the future research trend in the area.

关键词： Advanced oxidation processes H_(2)O_(2)in-situ generation Antibiotics degradation Combined AOPs Wastewater treatment

Enhancing Electrocatalytic Performance for Rechargeable Zn-Air Battery Through Interface engineering and Dual-Doping Strategy

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SSRN 2023年

作者： Min, Sojeong Min, Kyeongseok Lee, Geunchang Kim, Junseong Shim, Sang Eun Baeck, Sung-Hyeon Department of Chemistry and Chemical Engineering Education and Research Center for Smart Energy Materials and Process Inha University Incheon22212 Korea Republic of

In this study, we report on the preparation of uniform hollow-structured nanosphere which has abundant N, S co-doped CNT encapsulating heterostructured Co/CoS2 nanoparticles (Co/CoS2/NSCNT). The bifunctional electrocatalytic performance of these materials for ORR and OER is significantly enhanced by the synergistic effect of strongly coupled heterojunctions in the Co/CoS2 nanoparticles and abundant heteroatom dopants in the CNT shells. The Co/CoS2/NSCNT exhibits half-wave potential of 0.890 V vs. RHE and overpotential of 359 mV at 10 mA cm−2 for ORR and OER, respectively. Moreover, rechargeable ZAB assembled with the Co/CoS2/NSCNT catalyst delivers a specific capacity of 746 mAh gZn−1 and a peak power density of 156.8 mW cm−2, which exceed those values of precious metal-based ZAB (673 mAh gZn−1 and 136.9 mW cm−2, respectively). Additionally, the heteroatom-doped CNT shell prevents the dissolution and aggregation of transition metal-based active species during the electrochemical reaction in alkaline condition, thereby contributing excellent long-term cyclability of rechargeable ZAB. These findings demonstrate the potential of Co/CoS2/NSCNTs as high-performance electrocatalysts for rechargeable ZABs, and provide insights into the design of efficient and cost-effective electrocatalysts for energy storage applications. © 2023, The Authors. All rights reserved.

关键词： Electrocatalysts

Boosting the Electrocatalytic Performance for Rechargeable Zn-Air Battery: Synergistic Effect of Co/Cos2 Interface engineering and N, S Dual-Doping into Cnts

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SSRN 2023年

In this study, we report on the preparation of uniform hollow-structured Co/CoS2 nanoparticles encapsulated within N, S co-doped carbon nanotubes (NSCNTs). The bifunctional electrocatalytic performance of these materials for ORR and OER is significantly enhanced by the synergistic effect of strongly coupled Mott-Schottky junctions in the Co/CoS2 nanoparticles and abundant heteroatom dopants in the CNT shells. The Co/CoS2/NSCNT exhibits half-wave potential of 0.890 V vs. RHE and overpotential of 359 mV at 10 mA cm−2 for ORR and OER, respectively. Moreover, rechargeable ZAB assembled with the Co/CoS2/NSCNT catalyst delivers a specific capacity of 746 mAh gZn−1 and a peak power density of 156.8 mW cm−2, which exceed those values of precious metal-based ZAB (673 mAh gZn−1 and 136.9 mW cm−2, respectively). These findings demonstrate the potential of Co/CoS2/NSCNTs as high-performance electrocatalysts for rechargeable ZABs, and provide insights into the design of efficient and cost-effective electrocatalysts for energy storage applications. © 2023, The Authors. All rights reserved.

关键词： Electrocatalysts