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cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3)in Al_(2)O_(3)-AlPO_(4)for aldol condensation of methyl acetate with formaldehyde to methyl acrylate

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Chinese Journal of Chemical Engineering 2022年第12期52卷 172-183页

作者： Zhenyu Wu Zengxi Li Chunshan Li School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process and EngineeringKey Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Zhongke Langfang Institute of Process EngineeringChinese Academic of SciencesHebei 065000China

The bare amorphous Al_(2)O_(3)-AlPO_(4)and Cs/Al_(2)O_(3)-AlPO_(4)catalysts were developed for the aldol condensation of methyl acetate with formaldehyde to methyl *** structure and property of catalyst were characterized by XRD,XPS,BET,Pyridine-IR,FT-IR,^(27)Al-MASNMR,NH_(3)-/CO_(2)-TPD and *** correlation between structural features and acid-base properties was established,and the loading effect of the cesium species was *** to cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3),the weak-Ⅱacid and medium acid site densities and the product selectivity were *** the basic site densities of these catalysts were almost in proportion to the conversion of methyl *** loaded Cs could form new basic sites and change the distribution of acid sites which further enhance the catalytic *** a result,the 10Cs/8AlP was proved to be an optimal catalyst with the yield and selectivity of 21.2%and 85%for methyl acrylate *** the reaction,a deactivation behavior was observed on 10Cs/8AlP catalyst due to the carbon deposition,however,it could be regenerated by thermal treatment in the air atmosphere at 400℃.

关键词： Methyl acrylate(MA) Aldol condensation Al_(2)O_(3)-AlPO_(4) Penta-coordinated aluminum cooperative effects

Notes in accordions-organized MXene equipped with CeO_(2) for synergistically adsorbing and catalyzing polysulfides for high-performance lithium-sulfur batteries

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Journal of Energy Chemistry 2022年第7期31卷 502-510,I0013页

作者： Xiaochuan Chen Libo Li Yuhang Shan Da Zhou Wenjun Cui Yangmingyue Zhao School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

Limited by the shuttle effect, the application of lithium-sulfur batteries is not impressive. As an organ layered two-dimensional(2D) material, MXene has a great electrical conductivity and high specific surface area. Meanwhile, the introduction of metal oxides can restrain the shuttle effect. Hence, this paper prepared CeO_(2)/MXene as a cathode material of Li-S batteries. Ce and Ti can chemically adsorb S, and the interlayer structure of MXene can limit S while the interlayer space can alleviate volume *** discharge capacity at 0.5 C is as high as 1051.1 m Ah g^(-1), and 921.9 m Ah g^(-1) after 200 cycles. The average coulombic efficiency is 97.75%. The organized MXene with CeO_(2) like notes in accordions are new efficient materials for lithium-sulfur batteries.

关键词： cooperative effects MXene CeO_(2) Kinetics Lithium-sulfur batteries

Recent Developments of Atomically Dispersed Metal Electrocatalysts for Oxygen Reduction Reaction

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Chinese Journal of Chemistry 2023年第5期41卷 581-598页

作者： Ruoyu Pang Hongyin Xia Jing Li Shaojun Guo Erkang Wang State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchunJilin 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefeiAnhui 230026China School of Materials Science and Engineering Peking UniversityBeijing 100871China

Oxygen reduction reaction(ORR)is the pivotal portion in many electrochemical energy conversion and storage ***,the complex mechanisms and sluggish kinetics of ORR have also become one of the key issues hindering the d... 详细信息

关键词： Electrochemistry Materials science Oxygen reduction reaction Single-atom catalysts Electronic structure cooperative effects

Hydrogen Bonds in Perovskite for Efficient and Stable Photovoltaic

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Chinese Journal of Chemistry 2024年第11期42卷 1284-1306页

作者： Tian-yun Wang Yang-yang Hao Ming-zhe Zhu Guo-rui Cao Zhong-min Zhou College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdaoShandong266042 China College of Chemical Engineering Qingdao University of Science and TechnologyQingdaoShandong266042 China

Owing to their distinctive optical and physical properties,organic-inorganic hybrid perovskite materials have gained significant attention in the field of electronic devices,especially solar *** achievement of high-performance solar cells hinges upon the utilization of top-notch perovskite thin ***,the fabrication process involving solutions and the polycrystalline nature of perovskite result in the emergence of numerous defects within the perovskite films,consequently exerting a deleterious influence on the overall performance and stability of the *** the performance and stability of perovskite solar cells by additive engineering to suppress/passivate defects is a viable approach,which involves hydrogen bond interactions in these device engineering *** review explores the intrinsic hydrogen bonds in methylammonium and formamidium lead triiodide,while also considering cation rotations,phase transitions,and ***,the review classifies additives into distinct categories,including organic small molecules,polymers,nanodots,classical salts,ionic liquids,and molten *** various forms and characterization techniques of hydrogen bonds are discussed,as well as their potential synergistic effects in conjunction with other chemical ***,this review offers insights into the potential utilization of hydrogen bonds to further enhance the performance and stability of devices.

关键词： Perovskite solar cells Hydrogen bond Additive Performance Stability Charge transfer Inhibition cooperative effects

Novel Porphyrin-Containing Polymer Based Memristor for Synaptic Plasticity Simulation

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Chinese Journal of Chemistry 2022年第20期40卷 2451-2456页

作者： Linyi Bian Meng Xie Hao Chong Zhewei Zhang Guangyi Liu Qiushuo Han Jiaoyang Ge Zheng Liu Yang Lei Guangwei Zhang Linghai Xie Centre for Molecular Systems and Organic Devices State Key Laboratory of Organic Electronics and Information DisplaysJiangsu Key Laboratory for BiosensorsInstitute of Advanced MaterialsNanjing University of Posts&Telecommunications9 Wenyuan RoadNanjingJiangsu210023 China

The porphyrin-based copolymer PZnTPP-SFX is designed and synthesized by alternating porphyrin and spiro[fluorene-9,9'-xanthene]via Suzuki copolymerization.A simple memristor structure of ITO/ZnTPP-SFX/AlOx/Al was fabricated by spin-coating *** conventional synaptic plasticity is emulated using the single memristor including nonlinear transmission characteristics,spike-timing dependent plasticity and spike-rate dependent *** spike-voltage dependent plasticity is also found in the memristor which can selectively perform potentiation and depression behaviors at a unipolar *** with the device performance of uncoordinated metalloporphyrin polymer,it was found that oxygen vacancies diffuse and migrate into PZnTPP-SFX layer with the assist of coordination *** study suggests that porphyrin-based polymers have great promise for synaptic simulation of artificial neural network.

关键词： Copolymerization Spiro compounds Memristor cooperative effects Synaptic plasticity

Incorporation of flexible ionic polymers into a Lewis acid-functionalized mesoporous silica for cooperative conversion of CO2 to cyclic carbonates

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Chinese Journal of Catalysis 2019年第12期40卷 1874-1883页

作者： Ruqun Guan Xiaoming Zhang Fangfang Chang Nan Xue Hengquan Yang School of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan 030006ShanxiChina

A rational integration of multiple reactive centers into a combined unit to facilitate their cooperative effects is a smart approach for accelerating the catalytic ***,to achieve this goal,linear imidazolium-based ionic polymers were confined into the nanopores of mesoporous silica nanospheres anchored with homogeneously distributed zinc *** to the flexible character and the reinforced cooperative effects of the ionic liquid(nucleophile)and zinc species(Lewis acid)in the confined mesoporous structure,the resultant composite exhibited dramatically improved catalytic performance in the cycloaddition of CO2 with epoxides to form cyclic *** was in contrast to that observed for the individual catalytic ***,such a solid catalyst could be easily recovered and reused four times without a significant loss of activity.

关键词： Mesoporous silica Flexible ionic polymer cooperative effects CO2 utilization Heterogeneous catalysis

1,1'-Methylenediimidazolium-Based Multiple Hydrogen-Bond Donor Catalysts Facilitate the Cycloaddition of CO_(2) with Epoxides under Atmospheric Pressure

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有机化学 2024年第10期44卷 3198-3205页

作者： Chen Xuewei Yu Fangcai Tian Chuanhong National and Local United Engineering Laboratory for New Petrochemical Materials and Fine Utilization of Resources Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081

The quest for innovative hydrogen-bond donor(HBD)catalysts has led to a significant advancement in the field of organic *** the electron-withdrawing strength of imidazolium cations and the spatial requirements of hydrogen bond donors,a novel HBD catalyst based on the 1,1'-methylenediimidazolium scaffold by bridging two imidazolium cations with methylene was *** 1,1'-methylenediimidazolium-based catalysts exhibit excellent performance in the cycloaddition reaction of CO_(2) and epoxides,achieving up to 99% yield and 99%selectivity under mild conditions(atmospheric pressure,80℃ for 12 h,with 1 mol%catalyst).The geometric structure,atomic charge distribution,and synergistic effect of HBD catalysts were studied in detail through 1H NMR spectroscopy and density functional theory(DFT)*** research results indicate that the protons at positions C2-H,C2'-H,C5-H,and C5'-H on the imidazolium rings,as well as the protons on the bridged methylene,contribute to the formation of multiple hydrogen bonds with appropriate distance and synergistic effects,which are crucial for activating CO_(2) and *** research highlights the distinctive attributes of 1,1'-methylenediimidazolium-based catalysts and offers valuable insights into the development of highly efficient multiple HBD catalysts.

关键词： 1,1'-methylenediimidazolium multiple hydrogen-bond donor catalysts cycloaddition of CO_(2) cooperative effects density functional theory(DFT)calculation

The DFT Study of Five Member Rings’ Dissociation Effect in Methane Hydrate Single Cage Clusters

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The DFT Study of Five Member Rings’ Dissociation Effect in ...