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Photochemical cycloaddition and temperature-dependent breathing in pillared-layer metal–organic frameworks

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Science Bulletin 2019年第24期64卷 1881-1889页

作者： Qingqing Pang Binbin Tu lingyi Yang qiaowei li Department of Chemistry Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) and Shanghai Key Laboratory of Molecular Catalysis and InnovativeMaterials Fudan University

Single crystallinity of metal–organic frameworks(MOFs) enables the studies of their flexible behaviors with atomic precision. Here, we investigated the structural transformations triggered by photochemical cycloaddition and with temperature-dependent breathing in a series of pillared-layer MOF structures using a variety of pyrazolecarboxylate linkers for the layers and bipyridyl linkers as the pillars. The ethylenic double bonds from the pillars in close proximity undergo quantitative and seteroselective photochemical [2 + 2] cycloaddition upon UV irradiation, transforming the MOFs into structures with cyclobutane-based pillars. Furthermore, reversible breathing of the new pillared-layer MOF was evidenced by the 10.8% unit cell parameter change along c axis upon temperature change between 298 and 173 K. As revealed by single crystal X-ray diffraction, this transformation originates from the relative flattening of the wavy layers upon cooling. These two different types of characteristic structural transformations responding to inherent reactions and external stimuli happen at single crystalline state, providing a well-defined robust system with controlled flexibility.

关键词： Pillared-layer MOF Photochemical cycloaddition Structural transformation Breathing MOF Reticular chemistry

Reticular chemistry at the atomic,molecular,and framework scales

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Nano Research 2021年第2期14卷 335-337页

作者： Yue-Biao Zhang qiaowei li Hexiang Deng School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Department of Chemistry Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)and Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China Key Laboratory of Biomedical Polymers Ministry of EducationCollege of Chemistry and Molecular SciencesThe Institute of Technological Sciences and The Institute for Advanced StudiesWuhan UniversityWuhan 430072China

"There's plenty of room at the bottom."Feynmans talk has been frequently quoted for the advent of nanoscience,which gives profound perspectives of arranging atoms in the way we want[1].With the same bottom-up manner,reticular chemistry is concerned with linking of molecular building blocks by strong bonds to make crystalline open frameworks[2].The most im portant category practicing this bottom-up strategy at framework scale is m etal-organic frameworks(MOFs)coined in 1995[3],which leads to synthetic crystals featuring ultrahigh surface areas,fine-tuned pore metrics,and multivariate functionalities[4-16].The same strategy has also been successfully extended to crystalline covalent organic frameworks(COFs)from entirely organic building blocks through strong covalent bonds[17-19],whose crystal structures are now possible to be determ ined by 3D electron diffraction[20]and even X-ray diffraction[21].Recently,molecular weaving adds exotic flavors to reticular chemistry enabling the interlacing,knitting,and crocheting with molecular threads to make resilient nanotextiles[22].We envision the future of this field lays on the anisotropic reticular chem istry[23],where the components can be precisely arranged and manipulated along a specific *** atomic arrangement of various metals in the structures can be eventually read.

关键词： chemistry crystalline eventually

基于物联网的中波广播发射天线健康状态智能监测系统设计

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广播与电视技术 2024年第4期51卷 138-142页

作者：革命谢勇刚李龙李桥巍内蒙古广播电视传输发射中心呼伦贝尔广播发射中心台内蒙古021008 研究开发有限公司杭州分公司浙江310051 哈尔滨理工大学黑龙江150006

中波发射天线,作为中波广播发射的核心设施,其地理位置远离发射机房,因此易受到各种天气和地质条件的影响,从而可能引发播出事故。为确保广播电视的安全播出,并保障其平稳、高效运行,我们引入了广播发射天线健康状态智能监测系统。该系... 详细信息

中波发射天线,作为中波广播发射的核心设施,其地理位置远离发射机房,因此易受到各种天气和地质条件的影响,从而可能引发播出事故。为确保广播电视的安全播出,并保障其平稳、高效运行,我们引入了广播发射天线健康状态智能监测系统。该系统主要由天线垂直度监测、拉线拉力监测、拉线倾角监测以及上位机监测软件等四个核心组件构成。通过对各项数据的精准采集、高效处理,以及实时的在线监测与预警,本系统成功解决了对天线健康状态的实时监测问题,充分满足了发射天线的监测与预警需求。因此,该系统具有广阔的应用前景和重要的实用价值。

关键词：中波发射天线垂直度监测拉力监测倾角监测上位机监测软件

Construction of mixed carboxylate and pyrogallate building units for luminescent metal-organic frameworks

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Chinese Chemical Letters 2020年第3期31卷 813-817页

作者： Xiao lin Erlong Ning Xiaomin li qiaowei li Department of Chemistry iChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200433China

A metal-organic framework,Ce-FDM-50,was constructed by employing gallic acid featuring both carboxylate and pyrogallate as the coordinating sites and Ce(Ⅲ).The co-assembly of the carboxylates and pyrogallates with two metal ions have achieved a new type of paddle wheel secondary building *** building units were further joined by organic struts to obtain frameworks in sql *** synthetic approach could be expanded to five different lanthanide metals(Nd,Eu,Gd,Tb,Yb)for the construction of a series of isoreticular MOFs based on FDM-50,and even MTV-MOFs in which mixed lanthanide metals with specific ratios were *** addition,featuring the lanthanide metals as the inorganic nodes in the network,Tb-FDM-50 showed distinct luminescence properties that could be furtherly tuned for variable applications.

关键词： Metal-organic framework Secondary building units Gallic acid Bimetallic Luminescence

Functionality proportion and corresponding stability study of multivariate metal-organic frameworks

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Chinese Chemical Letters 2018年第6期29卷 837-841页

作者： Jie li Yecheng Wang Yan Yu qiaowei li Department of Chemistry iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan University State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University School of Physical Science and Technology Shanghai Tech University

Multivariate metal-organic frameworks（MTV-MOFs） with different ratios of terephthalate（BDC） linker and amino-benzenedicarboxylate（BDC-NH2） linker were synthesized through both direct synthesis from linker mixture and linker exchange of activated single-linker MOFs. Functionality proportion was impacted by the thermodynamics during the one-pot MOF construction, resulting in preference of BDC over BDC-NH2 in the MTV-MOF, in agreement with the quantum mechanics calculations. The functionality difference also affects the thermodynamics in the linker exchange process, as indicated by the more effective linker exchange in BDC-NH2-based IRMOF-3 than in BDC-based MOF-5. Furthermore,the thermal decomposition temperatures and chemical integrity upon ambient air exposure of these MOFs with variate functionalities were investigated, and it reveals that higher proportion of BDC in the MTV-MOF crystals contribute to both higher thermal and higher chemical stabilities.

关键词： Multivariate metal-organic frameworks Direct synthesis linker exchange Functionality proportion

化学学科发展新形势下研究生课程体系建设的实践探索与思考

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大学化学 2024年第6期39卷 50-54页

作者：李巧伟王华冬侯军利复旦大学化学系上海200433

目前化学学科发展面临科学技术进步迅速、多学科快速交叉融合以及信息大爆炸的机遇。如何建立适应新形势的课程体系,是当前化学研究生教育面临的难题之一。本文介绍了复旦大学化学系针对研究生培养过程中发现的课程体系短板,在强化化学... 详细信息

目前化学学科发展面临科学技术进步迅速、多学科快速交叉融合以及信息大爆炸的机遇。如何建立适应新形势的课程体系,是当前化学研究生教育面临的难题之一。本文介绍了复旦大学化学系针对研究生培养过程中发现的课程体系短板,在强化化学基础课程建设、加强实验安全课程建设、课程与科研联动补强等方面做出的实践探索。重点建设四门基础课程,强调知识与能力的一体化,培养科学评判精神;开设实验安全课程系统培养安全思维,提升研究生安全意识和应急处理能力;在培养方案上通过打破二级专业壁垒,建立优生优培特区,改革课程考核制度实现课程与科研的联动补强。

关键词：研究生课程课程建设基础课程实验室安全教育

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Synthesis,structure and luminescence properties of metal-organic frameworks based on benzo-bis(imidazole)

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Science China Chemistry 2014年第1期57卷 135-140页

作者： YIN XinBo SONG YuNa WANG Yang ZHANG liJuan li qiaowei Laboratory of Advanced Materials Fudan University School of Chemistry Beijing Institute of Technology Department of Chemistry Fudan University

Metal-organic frameworks(MOFs)constructed from conjugated organic ligands are candidates for hybrid photoactive materials with potential *** to that from the ligands only,the intensity and wavelength of the luminescence could be tuned after they were incorporated in extended *** this report,by using an organic ligand with azolate moiety,benzo-bis(imidazole)(H2BBI),we synthesized two new MOF *** 1([Co(H2BBI)(DMSO)2Cl2]n,DMSO=dimethyl sulfoxide),constructed from tetrahedral Co(II)and H2BBI,exhibits zigzag 1D ***,framework 2([Cu2(H2BBI)3(DMSO)6(NO3)4]n),a layered structure with hcb topology,was assembled from tetragonal pyramidal Cu(II)and ***,2 exhibits strong luminescence emission(ex=280 nm).A blue shift of 40 nm(from 359 nm to 319 nm)was observed in framework 2 compared to the free ligand,which could be explained by the ligand-to-metal charge transfer in the network.

关键词： metal-organic frameworks,luminescence,synthetic methodology,topological analysis

Mn-Based Two Dimensional Metal-Organic Framework Material from Benzimidazole-5,6-dicarboxylic Acid

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Chinese Journal of Chemistry 2016年第2期34卷 233-238页

作者： Erpan Zhang lili Zhang Zhe Tan Zhenguo Ji qiaowei li College of Materials and Environmental Engineering Hangzhou Dianzi University Hangzhou Zhejiang 310018 China Department of Chemistry Fudan University Shanghai 200433 China

A new two-dimensional metal-organic framework （MOF） structure has been synthesized by mild solvothermal reaction of MnC12o4H20 with 1H-benzimidazole-5,6-dicarboxylic acid （H3bidc） at 85℃. The structure has been characterized by single-crystal X-ray diffraction, powder X-ray diffraction （PXRD）, infrared spectroscopy （FT-IR）, and thermogravimetric analysis （TGA）. Single-crystal X-ray diffraction analysis revealed that this MOF is a five-coordinated Mn（II） compound exhibiting a layered 2D network, in which the hydrogen-bonding interactions between uncoordinated carboxylic oxygen atoms and N--H groups in the imidazole rings play a key role in the fi- nal 3D supramolecular architecture. This MOF shows high thermal stability up to 400℃. Furthermore, XRD pattern of the MOF structure was retained for up to 20 d after soaked in water, and only 2.8 wt% of the MOF was decomposed within the first 48 h in water.

关键词： metal-organic framework manganese benzimidazole-5,6-dicarboxylate water stability

Ordered Arrangement of Different Metals in Discrete and Infinite Building Blocks for Heterometallic Metal-Organic Frameworks Construction

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Chemical Research in Chinese Universities 2023年第6期39卷 902-906页

作者： XU Huoshu YAN Yu WU Yichen WANG Junyi TANG Yi li qiaowei Department of Chemistry Collaborative Innovation Center of Chemistry for Energy MaterialsShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200433P.R.China

Construction of sophisticated metal-organic frameworks(MOFs)with multiple kinds of metals is essential for further advancement of porous materials toward various *** and arrangement of the metals in the secondary building units(SBUs)greatly influence the MOF structures *** most of the previous heterometallic MOFs either have multiple kinds of discrete SBUs with different metals,or single kind of SBU with mixed metals inside,other forms of metal distribution still need further ***,a bifunctional linker is applied to achieving differential coordination toward different *** Ce and Cu serving as the carboxylate-philic and pyrazole-philic metal ions,three heterometallic MOFs(FDM-121—FDM-123)are *** addition to the common metal arrangement modes,the new MOFs provide a joint reticulation of a discrete SBU and an infinite chain-like SBU featuring different metals in FDM-121,and an assembly from heterometallic infinite chain-like SBU in *** study demonstrates the potential of bifunctional linkers for the design and synthesis of heterometallic MOFs and opens up the possibilities to create MOFs with tailored properties for specific applications.

关键词： Heterometallic Metal-organic framework Secondary building unit Bifunctional