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Selective Electrochemical Reduction of Nitrogen to Ammonia by Adjusting the Three-Phase Interface

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research 2019年第1期2019卷 66-77页

作者： Haiyan Wang Yuzhuo Chen Ruxue Fan Jiadong Chen Zhe Wang Shanjun Mao Yong Wang advanced materials and catalysis group Institute of CatalysisDepartment of ChemistryZhejiang UniversityHangzhou 310028China

The electrochemical nitrogen reduction reaction(NRR)provides a sustainable and alternative avenue to the Haber-Bosch process for ammonia(NH_(3))*** the great efforts made on catalysts and electrolytes,unfortunately,current NRR suffers from low selectivity due to the overwhelming competition with the hydrogen evolution reaction(HER).Here,we present an adjusted three-phase interface to enhance nitrogen(N_(2))coverage on a catalyst surface and achieve a record-high Faradic efficiency(FE)up to 97%in aqueous *** almost entirely suppressed HER process combined with the enhanced NRR activity,benefiting from the efficient three-interface contact line,is responsible for the excellent selectivity toward NH_(3),as evidenced by the theoretical and experimental *** strategy also demonstrates the applicability to other catalysts that feature strong H adsorption ability,to boost the FE for NH_(3) synthesis above 90%and to improve the NRR activity by engineering the catalysts.

关键词： synthesis solution selectivity

Layer-by-layer fabrication of montmorillonite coating immobilizing Cu_(2)O nanoparticles for continuously catalyzing glycerol to dihydroxyacetone

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Chinese Journal of Chemical Engineering 2024年第4期68卷 263-275页

作者： Kejin Li Jiahui Liu Dajian Li Xiaolan Chen Chunhui Zhou research group for advanced materials&sustainable catalysis(amsc) State Key Laboratory Breeding Base of Green Chemistry-Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310032China Qing Yang Institute for Industrial Minerals Qingyang 242804China Engineering research Center of Non-metallic Minerals of Zhejiang Province Zhejiang Institute of Geology and Mineral ResourcesHangzhou 310007China

Microreactors are increasingly used for green and safe chemical processes owing to their benefits of superior mass and heat transfer,increased yield,safety,and simplicity of ***,immobilizing catalysts in microreactors remains *** this investigation,a technique for creating Cu_(2)O/montmorillonite catalyst coating,using electrostatic attraction for layer-by-layer self-assembly,was *** montmorillonite film's morphology and thickness could be efficiently regulated by adjusting the degree of exfoliation and surface charge of montmorillonite,alongside layer-by-layer coating *** Cu_(2)O nanoparticles were immobilized using the flow deposition *** resulting Cu_(2)O@montmorillonite-film-coated capillary microreactor successfully transformed glycerol into *** conversion of glycerol and product selectivity could be controlled by adjusting the molar ratio of reactants,temperature,residence time,and Cu_(2)O *** maximum glycerol conversion observed was 47.6%,with a 27%selectivity toward *** study presents a technique for immobilizing montmorillonite-based catalyst coatings in capillary tubing,which can serve as a foundation for the future application of microreactors in glycerol conversion.

关键词： Microreactor Coating Montmorillonite Glycerol Cu_(2)O

Hydrothermal synthesis of manganese oxide encapsulated multiporous carbon nanofibers for supercapacitors

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Nano research 2016年第9期9卷 2672-2680页

作者： Haiyan Wang Jiang Deng Yiqing Chen Fan Xu Zhongzhe Wei Yong Wang advanced materials and catalysis group ZJU-NHU United R&D CenterCenter for Chemistry of High-Performance and Novel MaterialsDepartment of ChemistryZhejiang UniversityHangzhou 310028China

Hydrothermal carbonization (HTC) of biomass to produce one-dimensional carbon materials with hierarchical pores is of significant importance. Here, we fabricate composites of MnOx-encapsulated multiporous carbon nanofibers (M-MCNFs) from naturally available carbohydrates through a dopamine-assisted HTC/ templating process. The introduction of dopamine aids in the formation of the morphology of carbon nanofibers (CNFs) by enhancing the interactions between the hard-templates and carbohydrates. The chosen cryptomelane hard-templates, which are superior to traditional hard-templates, are converted into Mn3O4nanoparticles embedded in multiporous CNFs (MCNFs), eliminating the need for tedious post deposition procedures to introduce redox active sites. Hence, the obtained hybrids with large surface areas, hierarchical pores, and unique structures show great potential in supercapacitors. This economic and sustainable strategy paves a new way for synthesizing MCNFs and metal oxide-encapsulated MCNFs composites from biomass. [Figure not available: see fulltext.] © 2016, Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

关键词： hydrothermal carbonization multiporous carbon nanofiber manganese oxide encapsulated supercapacitor

Cyclocopolymerization of 1,6-heptadiene with ethylene by half-sandwich scandium catalysts

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Science China Chemistry 2014年第8期57卷 1150-1156页

作者： GUO Fang NISHIURA Masayoshi LI Yang HOU ZhaoMin State Key Laboratory of Fine Chemicals Department of Polymer Science and Engineering School of Chemical EngineeringDalian University of Technology Organometallic Chemistry Laboratory RIKEN advanced catalysis research group RIKEN Center for Sustainable Resource Science

The cyclocopolymerization of 1,6-heptadiene （HPD） with ethylene （E） by a series of half-sandwich scandium alkyl catalysts bearing various auxiliary ligands have been examined. Significant ligand influence on the copolymerization activity and selectivity was observed. In combination with one equivalent of [Ph3C][B（C6F5）4], the half-sandwich scandium dialkyl complexes bearing a Lewis base THF （1） or an NHC side arm （2） yielded the copolymer products together with cross-linked polymers in the copolymerization of HPD with ethylene. In contrast, the THF-free complexes Cp＇Sc（CH2C6H4NMe2-o）2 （3： Cp＇ = C5H5; 4： Cp＇ = CsMe4SiMe3） and the phosphine oxide side-arm containing complex （C5Me4SiMe2CH2（O）PPh2）Sc（CH2SiM%）2 （5） showed excellent activity and selectivity for the cyclocopolymerization reaction, without giving cross-linked products. The 1H and 13C NMR analyses revealed that the resulting copolymers consist of E-E sequences and six-membered ring methylene-1,3-cyclohexane （MCH） and five-membered ring ethylene-1,2-cyclopentane （ECP） units. The HPD content in the co- polymer products could be easily controlled by changing the feeding amount of HPD under 1 atm of ethylene.

关键词： scandium 1 6-heptadiene ethylene cyclopolymerization copolymerization

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Vicinal hydroxyl group-inspired selective oxidation of glycerol to glyceric acid on hydroxyapatite supported Pd catalyst

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Green Energy & Environment 2022年第4期7卷 691-703页

作者： Difan Li Xiuge Zhao Qingqing Zhou Bingjie Ding Anna Zheng Qingpo Peng Zhenshan Hou Key Laboratory for advanced materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

Selective oxidation of glycerol provides a feasible route towards the sustainable synthesis of high value-added ***,the hydroxyapatite(HAP)supported palladium(Pd)species were fabricated by impregnation and subsequent *** as-obtained heterogeneous Pd catalyst afforded not only excellent selectivity to glyceric acid(GLA)up to 90%with 59%conversion of glycerol but also good recyclability by using molecular oxygen as an oxidant under mild *** characterization of catalysts indicated that both the surface basicity and Pd sites on the catalyst played a crucial role in promoting glycerol ***,it demonstrated that the presence of the vicinal hydroxyl group of glycerol molecule can assist the oxidation reaction via forming a coordination between the vicinal hydroxyl group and Ca^(2+) sites on HAP-derived *** this catalytic process,the secondary hydroxyl of glycerol kept untouched and the primary hydroxyl of glycerol was converted into carboxyl group,while the Pd species acted as active centers for cooperatively promoting the subsequent oxidation to generate ***,this catalytic system can be extended widely for the oxidative conversion of other vicinal diols into the corresponding a-hydroxycarboxylic acids *** labeling experiment using H_(2)^(18)O confirmed that H_(2)O not only acted as solvent but also was involved in the catalytic *** the basis of the results,a possible reaction mechanism has been *** HAP-supported Pd catalytic system has been shown to serve as an effective approach for the upgrading of bio-derived vicinal diols to high value-added chemicals.

关键词： Hydroxyapatite Palladium Glycerol oxidation Glyceric acid Vicinal hydroxyl group

Hydrothermal base catalyzed depolymerization and conversion of technical lignin-An introductory review

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Carbon Resources Conversion 2019年第1期2卷 59-71页

作者： Malte Otromke Robin J.White Jorg Sauer Institute of catalysis research and Technology(IKFT) Karlsruhe Institute of Technology(KIT)Eggenstein-LeopoldshafenGermany sustainable Catalytic materials group Division Hydrogen TechnologiesFraunhofer Institute for Solar Energy Systems ISEHeidenhofstr.279110 FreiburgGermany GmbH Group Process TechnologyFrankfurt am MainGermany

Lignin represents the most significant potential source of sustainable aromatic ***,the vast majority of technical lignin could be sourced from industrial paper production and in particular the Kraft process,where it is conventionally combusted for chemicals recovery and heat generation(*** plant operation).While in recent years several efforts have concerned the conversion of native lignin(*** found in nature)during biomass processing,there has also been significant focus on the“Base Catalyzed”conversion of technical *** process is of significant interest,since it could be potentially integrated into existing Kraft mill *** following review paper focuses on the development of the hydrothermal base catalyzed depolymerization(HBCD)of lignin,as a basis to produce valuable chemical *** will be placed on NaOH catalyzed reactions in the aqueous phase,as this approach is considered the most *** is placed on reaction conditions and characterization of monomeric aromatic compounds from the HBCD ***,as largest product fraction,is also considered,however,these are seldom analyzed in detail in the literature and ideas on further use are *** review also addresses findings in literature concerning the assessment of the solid,liquid,and gas product streams arising from *** this paper,process conditions for HBCD reactions can be derived and it is shown that the solid phase has a high potential for further valorization and downstream processing.

关键词： catalyzed polymerization lignin

Applying ionic liquids as oil additives for gearboxes:Going beyond the state of the art by bridging the nano-scale and component level

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Friction 2023年第6期11卷 1057-1078页

作者： Azhaarudeen ANIFA MOHAMED FARUCK Philipp G.GRÜTZMACHER Chia-Jui HSU Dominik DWORSCHAK Hsiu-Wei CHENG Markus VALTINER Kristof STAGEL Philipp MIKSOVSKY Apurba Ranjan SAHOO Aitor SAINZ MARTINEZ Katharina BICA-SCHRODER Michael WEIGAND Carsten GACHOT Institut für Konstruktionswissenschaften und Produktentwicklung(IKP) Tribology Research DivisionTU WienVienna1060Austria Institut für Angewandte Physik(IAP) Applied Interface Physics research groupTU WienVienna1040Austria Institut für Angewandte Synthesechemie(IAS) Sustainable Organic Synthesis and Catalysis research groupTU WienVienna1060Austria

Ionic liquids(ILs)have been used effectively in many applications for reducing problems related to friction and *** this work,the potential of ILs as an anti-wear and extreme pressure lubricant additive for high load-carrying gearbox applications such as helicopter transmissions has been *** halide-free ILs:P_(8881)(BuO)_(2)PO_(2)^(-)(1)and P_(8881)(MeO)_(2)PO_(2)^(-)(2),which are blended at 5 wt%each into a standard non-additivated FVA2 base oil(BO)are *** solid-liquid interface,friction and load-carrying capacity,and wear(scuffing)behavior are studied on the nano-,lab-,and component-scale,respectively,at a different range of temperature and loading conditions by using the atomic force microscopy(AFM),Schwing-Reib-Verschleiβ(SRV)friction tests,and Brugger tests,as well as forschungsstelle für zahnrader und getriebebau(FZG)back-to-back gear test *** AFM analysis shows nearly no change of adhesion over the full range of studied temperature for the IL blends compared to the ***,IL blends demonstrate a very stable coefficient of friction(COF)of around 0.16,which even decreases with increasing test temperatures ranging from 40 to 120℃.A clear reduction in COF up to 25%is achieved by adding only 5 wt%of the investigated Ils in the BO,and the Brugger tests also show a pronounced enhancement of load-carrying ***,on the component-scale,a significant improvement in gear scuffing performance has been observed for both used IL blends.A detailed characterization of the wear tracks from the SRV friction tests via the transmission electron microscopy(TEM)revealed the formation of a phosphate(P-O)-based amorphous tribo-chemical layer of about 20 nm ***,this work may present an approach for Ils to be used as an additive in conventional lubricants due to their ability to enhance the lubrication properties,making them an alternative lubricant solution for high load-carrying gearbox applications.

关键词： ionic liquids(ILs) additives gears scuffing friction load-carrying capacity

Neodymium-catalyzed Polymerization of C5 Fraction: Efficient Synthesis of 1,3-Pentadiene-isoprene Copolymer Rubbers

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Chinese Journal of Polymer Science 2019年第7期37卷 674-680页

作者： Jin-Yan Hou Fang Guo Qian Hu Yang Li Zhao-Min Hou State Key Laboratory of Fine Chemicals Department of Polymer Science and EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 116012China Fushun Yikesi New Material Co. Ltd.Fushun 113000China advanced catalysis research group RIKEN Center for Sustainable Resource Science2-1 HirosawaWakoSaitama 351-0198Japan

The polymerization of C5 fraction without separation and concentration by using a commercial available Nd(P204)3/ AliBu3/AlEt2Cl has afforded for the first time a new kind of 1,3-pentadiene-isoprene random copolymers as rubber materials. Isoprene (IP) and E-1,3-pentadiene (EPD) acted as polymerization monomers, cyclopentadiene acted as poison, and other substances like alkanes, monoolefins, Z-1,3-pentadiene acted as solvents in this multicomponent C5 fraction polymerization system. The data of kinetic experiments, NMR, and DSC indicated that the polymerization of C5 fraction by Nd(P204)3/AliBu3/AlEt2Cl afforded the IP-EPD random copolymers. By controlling polymerization conditions such as [Al]/[Nd]/[Cl] molar ratio and polymerization temperature, the random EPD-IP copolymers containing high cis-1,4-poly(IP)(with selectivity 96%) and moderate cis-1,4-poly(EPD)(with selectivity 60%) units with a low glass transition temperature (about 60 ℃), controllable molecular weight (Mn = 3.8 × 10^4-14.3 × 104), and moderate molecular weight distribution (Mw/Mn = 2.17-2.78) were obtained in a high yield.

关键词： C5 fraction Neodymium Isoprene 1,3-Pentadiene Copolymerization

Tuning Structures and Microenvironments of Cu-Based Catalysts for sustainable CO_(2) and CO Electroreduction

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Accounts of materials research 2023年第3期4卷 264-274页

作者： Ximeng Lv Zhengzheng Liu Chao Yang Yali Ji Gengfeng Zheng Laboratory of advanced materials Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China

CONSPECTUS:The carbon balance has been disrupted by the widespread use of fossil fuels and subsequent excessive emissions of carbon dioxide(CO_(2)),which has become an increasingly critical environmental challenge for human *** production and use of renewable energy sources and/or chemicals have been proposed as important strategies to reduce emissions,of which the electrochemical CO_(2)(or CO)reduction reaction(CO_(2)RR/CORR)in the aqueous systems represents a promising *** by the capacity of manufacturing high-value-added products(e.g.,ethylene,ethanol,formic acid,etc.)with a net-zero carbon emission,copper-based CO_(2)RR/CORR powered by sustainable electricity is regarded as a potential candidate for carbon ***,the diversity of selectivities in copper-based systems poses a great challenge to the research in this field and sets a great obstacle for future *** date,scientists have revealed that the electrocatalyst design and preparation play a significant role in achieving efficient and selective CO_(2)-to-chemical(or CO-to-chemical)*** substantial efforts have been dedicated to the catalyst preparation and corresponding electrosynthesis of sustainable chemicals from CO_(2)/CO so far,most of them are still derived from empirical or random searches,which are relatively inefficient and *** of the mechanism studies have suggested that both intrinsic properties(such as electron states)and extrinsic environmental factors(such as surface energy)of a catalyst can significantly alter catalytic ***,these two topics are mainly discussed for copper-based catalyst developments in this ***,we provided a concise and comprehensive introduction to the well-established strategies employed for the design of copperbased electrocatalysts for CO_(2)RR/*** used several examples from our research group,as well as representative studies of other research groups in this field d

关键词： catalyst interfacial hydrolysis