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2019中国化学会第十五届全国计算（机）化学学术会议

作者： Qin-Kun Li Yulan Han Ke Ye 张国桢 Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Department of Materials Science and NanoEngineering Rice University 中国科学技术大学

heterogeneous catalysis is central for efficient energy and matter transformation in chemistry industry. Enormous efforts in catalysis community have been exerted to precise understanding of active sites, including identification of their atomic structures and establishment of structure-activity relationship. Meanwhile, the interaction between adjacent active sites has long been underappreciated. Yet a couple of recent reports suggest non-negligible cooperative catalytic effects between neighboring active centers.[1,2] It is noteworthy that the emerging single-atom catalysts(SACs) can serve as ideal model systems to study new physics and chemistry brought by such cooperative effect. We recently showed that neighboring FeN sites embedded in graphene can exhibit cooperative spin transition induced by the adsorption of CO.[3] It suggests non-trivial cooperative communication between two FeN sites mediated by the graphene network. Then we studied the impact of adjacent FeN sites on the oxygen reduction reaction(ORR). We first found that the midway region between two adjacent FeN of proper distances could act as the active center for two-electron reduction pathway of ORR that produces hydrogen peroxide. Intriguingly, this pathway relies on weakly physisorption of all species related. Further, we found that as the distance between two FeN sites decreases, the rate-limiting step of four-electron reduction pathway of ORR is more energetic unfavorable, suggesting a negative impact of proximity of FeN sites on ORR. Our computation results suggest the neighboring effect in high-density SACs can alter energy profiles of catalytic reaction pathways and thus deserves much attention. Meanwhile, we investigated the impact of distance of two adjacent active centers in a monodispersed molybdenum SAC on nitrogen reduction reaction(NRR). We found that as two MoN sites are sufficiently close, the energy change in rate-limiting step could be appreciably affected. More importantly, two ad

关键词： density-functional calculations heterogeneous catalysis single-atom catalysts inter-site interactions reaction mechanism

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Solvent Induced Three Silver Metal-organic Materials as Catalysts for Tandem Acylation-Nazarov Cyclization

Solvent Induced Three Silver Metal-organic Materials as Cata...

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河南省化学会2016年学术年会

作者： Chao Huang Liwei Mi Hongwei Hou Center for Advanced Materials Research Zhongyuan University of Technology College of Chemistry and Molecular Engineering Zhengzhou University

Metal-organic frameworks(MOFs) made from metal ions linked by organic ligands have provided an interesting platform for engineering immobilizing well-defined molecular single-site catalysts and propelled a growing amount of attention into CP-based heterogeneous catalysis. In our continuing quest to develop MOFs-catalyzed tandem pyrrole acylation-Nazarov cyclization reaction with α,β-unsaturated carboxylic acids for the synthese of cyclopentenone[b]pyrroles, which are key intermediates in the synthesis of natural product(±)-roseophilin, solvent induced a series of Ag-based coordination polymers(1-3) have been sythesized under solothermally conditions. When the polarity of solvent changed, the structure of 1 with hydrophilic channels can change into the structure of 2 with Ag-Ag-Ag interaction and hydrophilic channels, and back into the structure of 3 without hydrophilic channels. The polarity and van der waals volume of solvent can influence the related linking modes and regulate the structures of complexes 1-3. Futhermore, 1-3 have shown to be effective heterogeneous catalysts for the tandem acylation-Nazarov cyclization reaction. The rates of catalytic reactions strongly depend on the MOFs hydrophilic channels, Ag-Ag-Ag synergetic interaction, and the dimensions of organic substrates and products. Especially, the unique structural features of 2, including hydrophilic channels and Ag-Ag-Ag synergetic interaction, endow 2 all of the desired features for the MOFs-catalyzed tandem acylation-Nazarov cyclization reaction, which can greatly increase the yield of total synthesis of(±)-roseophilin.

关键词： heterogeneous catalysis solvent effect tandem acylation-Nazarov cyclization reaction

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CO Adsorption Site Control by Atomic-Level Mixing of Immiscible Cu and Ru

CO Adsorption Site Control by Atomic-Level Mixing of Immisci...

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中国化学会第十九届全国催化学术会议

作者： Bo Huang Hirokazu Kobayashi Hiroshi Kitagawa Department of Chemical Engineering School of Chemical Engineering and TechnologyXi'an Jiaotong University Division of Chemistry Graduate School of ScienceKyoto UniversityKitashirakawa-Oiwakecho

CO oxidation is key reaction in hydrogen purification for fuel cell and three-way catalysis. Platinum group metal ruthenium has already been commercialized in such as Ene-Farm(a household fuel cell unit in Japan), however, the high price strongly restricted its further application in hydrogen energy economy as well as three-way catalysis in China. To develop promising candidate materials instead of ruthenium metal is greatly expected.

关键词： CO oxidation heterogeneous catalysis Immiscible Nanoalloy Single Atom Site Adsorption Site Change

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Porous Sliver Coordinated Polymer Catalyzed Carboxylative Cyclization of Carbon Dioxide

Porous Sliver Coordinated Polymer Catalyzed Carboxylative Cy...

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中国化学会第八届全国配位化学会议

作者： Zhen Zhou Yefei Wang Cheng He Chunying Duan State Key Laboratory of Fine Chemicals Dalian University of Technology

The utilization and transformation of abundant gaseous waste,carbon dioxide as C1 source,into valuable chemical products deserves persistent attentions for the chemists due to the requirement of the green chemistry and atomic *** now,a great deal of efforts has been made to develop porous materials towards the adsorption and fixation of carbon *** the numerous examples,the porous coordination polymer,metal-organic frameworks(MOFs),have been regarded as an excellent platform because of their intriguing structural diversity and modular nature and facile ***(Ⅰ) complexes,which function as o-and/or nLewis acids,have been shown to be powerful catalysts for alkyne transformations due to its delectronic configuration,favouring interactions with the carbon-carbon n-bond of alkynes,referred to as *** carboxylative cyclization of propargylic alcohols and carbon dioxide to amethylene cyclic carbonates,which are important natural products with potential bioactivity and chemical value,have shown a great promise pathway for the direct incorporation of carbon dioxide and achieved considerable reactivity and selectivity catalyzed by many kinds of Ag-based catalysts via the benign n-activation,as we *** combining the alkynopholic Ag(Ⅰ) ion into the porous and unique structural features of MOFs,it is possible to develop a potential synthetic strategy to construct efficient heterogeneous catalysts for the reactions starting with alkynes and its ***,we present the synthesis of one sliver-based MOFs material,Ag-1,with three-dimensional Kagome lattice topology by the incorporation of the tetrakis(4-carboxyphenyl)ethylene(H TCPE) moiety as the four-point connected node via hydrothermal ***-crystal X-ray structural analysis revealed that Ag-1 crystallizes in C2 cspace group,and with two kinds of channels along the *** catalytic experiments were initially investigated for the carboxylic cyclization of pro

关键词： Metal-organic frameworks carbon dioxide convertion heterogeneous catalysis

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基于三元催化剂摩尔比例选择性合成不同结构螺环化合物(英文)

基于三元催化剂摩尔比例选择性合成不同结构螺环化合物(英文)

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中国化学会全国第十一届有机合成化学学术研讨会

作者：庞韬 Yu Sun Wei-Jian Xue Yan-Ping Zhu Guang-Ao Yu 吴安心华中师范大学安庆师范学院

The unusual and unexpected effects which can result from heterogeneous metal catalysts provide much potential for the efficient construction of complex molecules from starting simple *** prevalence of correlative approaches continues to urge organic chemists to develop further novel methods in synthetic *** the same reactants under different catalytic conditions,the selective synthesis of different products has been widely utilized as a classical method. To the best of our knowledge,chemoselective synthesis of different products from the same starting materials achieved by controlling the molar ratio of ternary metal catalysts is yet to be *** new,easy-to-perform,and efficient GaCl/InCl/Cu(I)-catalyzed processes using readily available substrates have been *** on the molar ratio of ternary catalysts,the reaction between naphthalen-2-ol 1a and formaldehyde 2 exclusively yields either six-membered spironaphthalenone or five-membered *** is necessary to investigate the actions of two composite catalysts on reaction mechanism with our further research carried on in future.

关键词： heterogeneous catalysis Chemoselectivity Reaction mechanisms Diels-Alder reaction Spiro compounds

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Synthesis, structure and heterogeneous catalytic property of a mixed valence copper coordination polymer based on trinuclear clusters

Synthesis, structure and heterogeneous catalytic property of...

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河南省化学会2020年学术年会

作者： Heng Zhang Xun Feng Dong-Sheng Deng Li-Ya Wang College of Chemistry and Molecular Engineering Zhengzhou University College of Chemistry and Chemical Engineering Luoyang Normal University School of Life Science and Technology Nanyang Normal University

To improve the reaction efficiency and high selective catalysis system from organic synthesis one that features the use of inexpensive cuprocupric compounds.A novel trinuclear mixed valence cluster,{Cu[(SQPA)(4,4′-bipy)(HO)]·16HO}(1)(HSQPA=2-sulfonylquinlium-8-yloxy)-phthalic acid,4,4′-bipy=4,4′-bipyridine),has been hydrothermally synthesized and structurally *** 1,there are there independent copper coordination polyhedrons,Cu NO,Cu NO,Cu *** studies of catalysis experiments show that 1 is An excellent catalytic performance in the C-N coupling reaction between aryl-boric acid and imidazole rings.

关键词： Trinuclear mixed valence heterogeneous catalysis

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Porous amine-functionalized coordination polymers as cooperative and size-selective catalysts for acetylation of phenols

Porous amine-functionalized coordination polymers as coopera...

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河南省化学会2016年学术年会

作者： Dongsheng Deng Hui Guo Jingzhi Yang Baoming Ji College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function-Oriented Porous Materials Luoyang Normal University

Amine-functionalized porous coordination polymers(PCPs) are a burgeoning class of solid catalysts with uniform catalytic sites and open channel structures for shape- and size-selective reactions. As part of our extensive investigations of amine-based porous coordination frameworks, we reported herein on the catalytic capacity of Zn(L)(aip)(H2aip = 5-aminoisophthalic acid, L = N,N-di(pyridine-4-yl)biphenyl-4,4’-dicarboxamide) towards acetylation of various phenols with varying electronic properties and reactivities. In particular, the unique structural features of this PCPs, including non-coordinated amine groups as accessible catalytic sites and suitable channel size and shape, endow the PCPs with all of the desired features for the PCPs-catalyzed acetylation reactions, including heterogeneous catalyst,high catalytic activity, robustness, and excellent cooperative and size-selectivity.

关键词： porous coordination polymers heterogeneous catalysis cooperative catalyst acetylation reaction

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APPLICATION OF LOW CATALYCITY HEAT-SHIELDING COATINGS AT THE ENTRANCE IN THE MARS ATMOSPHERE

APPLICATION OF LOW CATALYCITY HEAT-SHIELDING COATINGS AT THE...

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第4届国际流体力学学术会议

作者： V.L.Kovalev N.E.Afonina V.G.Gromov Moscow State University named after M.V. Lomonosov Moscow 119899 Russia Moscow State University named after M.V. Lomonosov Moscow 119899 Russia Moscow State University named after M.V. Lomonosov Moscow 119899 Russia

＜正＞In this study the effect of catalytic surface properties on heat exchange near the bottom surface of a space vehicle entering the Martian atmosphere was studied. It was shown that the catalytic properties of the frontal and bottom surfaces may significantly influence （up to several times） the levels of heat fluxes. It was found also that the physical adsorption of oxygen atoms leads to an increase of heat fluxes, on the surface regions with a temperature lower than 600 K.

关键词： enter the atmospheres high-temperature thermal protection systems heterogeneous catalysis

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Effect of Molecular Structure on Diffusion of Alcohols through Type-A Zeolite Pores(0.5 nm)

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材料科学与工程（中英文A版） 2021年第2期11卷 48-55页

作者： Bryan Fernández-Solano Julio F.Mata-Segreda Biomass Laboratory School of ChemistryUniversity of Costa Rica 11501-2060Costa Rica

Drying kinetics for alcohol-soaked type-A zeolite(pore size 0.5 nm)was determined at 50°C for 12 small-molecule alcohols(from C1 to C10).The second-phase of drying of wet porous materials reports on the mass-transfer characteristics within the solid *** stage follows pseudo first-order kinetics(k1),and the second-order rate constant k2=k1/(fluxional area)was found to correlate with the surface tension of the liquids imbibing the solid matrix(p<0.002).k2 values decrease along the homologous linear alcohols,and branched-chain alcohols diffuse faster than their linear analogues due to their lower surface *** independent contribution was found from the molecular size of the alcohols in the experiment reported *** velocity and enthalpy of vaporisation of the liquids were not found to be significant independent variables,*** find agrees with the notion that liquid movement in pores is governed during the drying processes by the liquid chemical potential gradient between the pore space and gas phase above the porous particle surfaces,this gradient being a function of the molecular cohesion of the moving liquid front(surface tension,g).The results can be expressed by the linear Gibbs-energy relation log(k2/s^(-1)·m^(-2))=(2.5±0.5)-(1.6±0.2)×10^(2)(g/J·m^(-2)).

关键词： Drying kinetics liquid diffusion through pores surface tension heterogeneous catalysis

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