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A three-dimensional polycyclic aromatic hydrocarbon based covalent organic framework doped with iodine for electrical conduction

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Chinese Chemical Letters 2023年第4期34卷 601-604页

作者： Ruofan Li guolong xing Hui Li Shen Li Long Chen Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China Zhejiang Engineering Laboratory for Green Syntheses and Applications of Fluorine-Containing Specialty Chemicals Institute of Advanced Fluorine-Containing MaterialsZhejiang Normal UniversityJinhua 321004China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012China

Covalent organic frameworks(COFs) are a class of crystalline porous organic materials with variable structures and fascinating properties. The intrinsic low conductivity impedes their widely application in optoelectronic. Iodine doping is an effective way to enhance the electrical conductivity of COFs. Here, a novel 3D imine COF with lvt topology is synthesized from two different pentacene derivatives with the same core in the form of structural complementarity. DDHP-COF is a highly crystalline material featuring high surface area of 1679 m^(2)/g and excellent thermal stability up to 490 ℃. Upon doping with iodine, the electrical conductivity can reach as high as 1.5×10^(-2)S/m which is significantly enhanced over 6 orders of magnitude compared with the pristine COF.

关键词： Three-dimensional Covalent organic frameworks Imine linkage Chemical doping Electrical conduction

Direct pore engineering of 2D imine covalent organic frameworks via sub-stoichiometric synthesis

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Science China Chemistry 2022年第1期65卷 190-196页

作者： Xiao Yang Zhen Xie Ting Zhang Guang Zhang Ziqiang Zhao Yong Wang guolong xing Long Chen Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China

Two-dimensional covalent organic frameworks(2D COFs)bearing various topologies can be precisely designed based on the symmetry of *** pore environment can be further regulated via either pre-functionalization of the monomers or post-modification of the *** them,sub-stoichiometric synthesis is an efficient method which can mediate uncondensed functional moieties periodically arranged in the COF ***,a series of imine-linked 2D COFs with specifically decorated formyl or amino groups were selectively synthesized via sub-stoichiometric formyl *** molar ratios of the monomers directly determine the structures of the resulting COFs with periodic vertex *** COF with polar amino sites could efficiently capture CO_(2) and H_(2)*** work demonstrates tuning the stoichiometry of the monomers could facilely modulate the functions of the pore *** also provides insights into constructing novel COFs with complex structures for targeted applications.

关键词： covalent organic frameworks sub-stoichiometric periodic vertex vacancies

Donor-acceptor 2D covalent organic frameworks for efficient heterogeneous photocatalyticα-oxyamination

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Science China Chemistry 2021年第5期64卷 827-833页

作者： Huan Liu Xiaoli Yan Weiben Chen Zhen Xie Shen Li Weihua Chen Ting Zhang guolong xing Long Chen Department of Chemistry Institute of Molecular PlusTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China College of Chemistry and Green Catalysis Center Zhengzhou UniversityZhengzhou 450001China

Covalent organic frameworks(COFs)have received widespread interest due to their high porosity,excellent crystallinity,tailorable structures,and broad application *** has been demonstrated that proper combination and arrangement of electron donor and acceptor units in 2D conjugated COF lattice could promote efficient charge separation and electron transfer,and thus is beneficial for *** this article,three donor-acceptor(D-A)2D COFs were prepared by Schiff base reaction of electron acceptor 4,4′,4′′,4′′′-(benzo[1,2-d:4,5-d′]bis(oxazole)-2,4,6,8-tetrayl)tetraaniline(BBO)with different electron donors:thieno[3,2-b]thiophene-2,5-dicarbaldehyde(TT),benzo[1,2-b:4,5-b’]dithiophene-2,6-dicarboxaldehyde(BDT)and terephthalaldehyde(Ph),*** D-A 2D COFs exhibited prominent photocatalytic activity towardsα-oxyamination of 1,3-dicarbonyl with 2,2,6,6-tetramethyl-1-piperdinyloxy(TEMPO)upon visible light *** these D-ABBO-COFs,DTT-ABBO-COF exhibited the highest photocatalytic rates,which can be ascribed to the more negative highest occupied molecular orbital(HOMO)and narrower *** excellent stability,high activity and superior recyclability render DTT-ABBO-COF as a potential and environmentally friendly heterogeneous catalyst forα-oxyamination.

关键词： covalent organic frameworks donor-acceptor benzodioxazole heterogeneous photocatalysis α-oxyamination

Skeleton Engineering of Isostructural 2D Covalent Organic Frameworks: Orthoquinone Redox-Active Sites Enhanced Energy Storage

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CCS Chemistry 2021年第2期3卷 696-706页

作者： Miao Li Jingjuan Liu Yusen Li guolong xing Xiang Yu Chengxin Peng Long Chen Department of Chemistry Institute of Molecular Plusand Tianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072 Analytical and Testing Center Jinan UniversityGuangzhou 510632 School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093

The integration of redox-active sites into the skeleton of open-framework materials is an efficient strategy toward high-performance organic electrodes for energy storage *** this work,stepwise introduction of ketone(KT)groups to the skeletons of isostructural two-dimensional(2D)covalent organic frameworks(COFs)was realized by the condensation of 2,4,6-triformylphloroglucinol(Tp,as nodes)with a series of ditopic diamines,which contained none,one,two,and four KT moieties in each linker units,*** precise control of the redox functionalities at the molecular level,combined with regular built-in channels in these KT-Tp COFs endowed them with superior capacitances and excellent rate capabilities for energy *** particular,2KT-Tp COF and 4KT-Tp COF electrodes exhibited high capacitances of 256 and 583 F g−1 at a discharge rate of 0.2 A g−1,respectively,which outperformed most reported COF-based *** importantly,exceptional long-term cyclabilities(>92%capacitance retention)were achieved even after 20,000 cycles at a high current density of 5 A g−1 for these KT-Tp *** results demonstrated that orthoquinone moieties rendered enhanced performance than the redox COFs with isolated carbonyl groups.

关键词： redox-active covalent organic frameworks,orthoquinone supercapacitor energy storage

An In Situ Film-to-Film Transformation Approach toward Highly Crystalline Covalent Organic Framework Films

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CCS Chemistry 2022年第5期4卷 1519-1525页

作者： Yongkang Lv Yusen Li Guang Zhang Zhongxiang Peng Long Ye Yu Chen Ting Zhang guolong xing Long Chen Department of Chemistry Institute of Molecular PlusTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072 School of Materials Science and Engineering Tianjin UniversityTianjin 300072 Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049

Fabrication of highly crystalline covalent organic framework(COF)films with tunable thickness and good substrate adaptability remains a substantial ***,we have developed an effective approach for fabricating crystalline COF films based on elaborately designed bifunctional A_(2)B_(2) ***,amorphous drop-casted monomer[e.g.,1,4-bis(4-formylphenyl)-2,5-bis((4-aminophenyl)ethynyl))benzene(BFBAEB)]films were directly transformed into corresponding highly crystalline BFBAEB-COF film upon in situ vapor-assisted self-polycondensation in high yields(93-97%).The thickness of the BFBAEB-COF film could be modulated readily by varying the monomer *** crystalline COF films could be grown on various substrates,including silicon,indium-doped tin oxide(ITO),glass,and ***,such an in situ film-tofilm transformation approach has been demonstrated as versatile and applicable to different A2B2 *** work provides a novel pathway toward homogeneous and highly crystalline COF films,representing a key step forward to explore the application of COFs.

关键词： COF films A_(2)B_(2)monomers self-polycondensation in situ transformation

一步碳化多孔有机材料制备多孔碳及其性能的研究

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化学学报 2018年第5期76卷 366-376页

作者：闫婷婷邢国龙贲腾吉林大学化学学院长春130012

开发并利用清洁的、可再生的能源是解决环境污染问题和能源短缺的有效方法.碳化含碳量较高的多孔有机材料制备的多孔碳,具有较高的比表面积,良好的物化稳定性,优良的机械性能等优点,在清洁能源的存储、分离、能量的存储与转化领域有广... 详细信息

开发并利用清洁的、可再生的能源是解决环境污染问题和能源短缺的有效方法.碳化含碳量较高的多孔有机材料制备的多孔碳,具有较高的比表面积,良好的物化稳定性,优良的机械性能等优点,在清洁能源的存储、分离、能量的存储与转化领域有广泛的应用.常见的由多孔有机材料制备多孔碳的方法主要是非活化碳化法和活化碳化法.不同的制备方法得到的多孔碳形貌,孔结构各不形同.多孔碳材料自身的结构性质可以影响其应用.合理的设计并调控多孔碳的"孔",发挥孔尺寸的"筛分效应"可以有效地对气体进行存储和分离.在锂电等能量转化领域,"限域效应"是影响锂电性能的重要因素.多孔碳材料中较小的孔可以限域活性成分,而较大的孔可以快速传输,两种孔的协同效应可以使锂电性能大大提升.本综述系统地归纳了一步碳化多孔有机材料制备多孔碳的方法及其优势,详细地介绍了其在气体吸附、存储、分离以及电化学等领域的应用.最后,结合多孔碳材料的研究现状,提出由多孔有机材料制备多孔碳材料所面临的挑战,同时也展望了多孔碳材料的应用前景.

关键词：多孔有机材料多孔碳气体吸附碳化电化学

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结构基元对多孔芳香骨架气体吸附性能的影响

高等学校化学学报 2018年第5期39卷 1072-1077页

作者：闫婷婷邢国龙贲腾裘式纶吉林大学化学学院长春130012

通过选择2种不同的结构基元:1,3,5-三溴苯(TBB)和3,3',5,5'-四溴-1,1'-联苯(TBBP),利用Yamamoto型Ullmann偶联反应,制备了2种类似的多孔芳香骨架(PTBB和PTBBP),并对其进行了结构表征.结果表明,2种多孔芳香骨架在性质上具有一定的相似性... 详细信息

通过选择2种不同的结构基元:1,3,5-三溴苯(TBB)和3,3',5,5'-四溴-1,1'-联苯(TBBP),利用Yamamoto型Ullmann偶联反应,制备了2种类似的多孔芳香骨架(PTBB和PTBBP),并对其进行了结构表征.结果表明,2种多孔芳香骨架在性质上具有一定的相似性,均显示出较高的比表面积、均一的孔径分布以及良好的热稳定性,并且在气体吸附与存储方面有着潜在的应用.由于结构基元本身性质上的差异,导致了两者在比表面积及气体吸附等性质上的差异.

关键词：多孔芳香骨架气体吸附结构基元偶联反应

核电站不间断电源系统异常停机的原因分析与改进措施

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上海电气技术 2020年第3期13卷 50-54页

作者：董磊星国龙张立国中广核运营有限公司广东阳江529941

某核电站2号机组运行期间进行系统断电试验时,发生不间断电源系统配电盘整盘失电故障,导致核电站多台重要设备失去电源。对这一核电站不间断电源系统异常停机故障的原因进行了分析,并提出了为通信卡附加高精度相位检测模块,调整主机探... 详细信息

某核电站2号机组运行期间进行系统断电试验时,发生不间断电源系统配电盘整盘失电故障,导致核电站多台重要设备失去电源。对这一核电站不间断电源系统异常停机故障的原因进行了分析,并提出了为通信卡附加高精度相位检测模块,调整主机探测电路阈值等改进措施。

关键词：核电站不间断电源故障分析

MLXR: multi-layer obstacle-avoiding X-architecture Steiner tree construction for VLSI routing

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Science China(Information Sciences) 2017年第1期60卷 211-213页

作者： xing HUANG Wenzhong GUO Genggeng LIU guolong CHEN College of Mathematics and Computer Sciences Fuzhou University Key Laboratory of Network Computing and Intelligent Information Processing (Fujian Province) Fuzhou University

Dear editor,Rectilinear Steiner minimal tree(RSMT)has been widely used in several modern very large scale integration(VLSI)circuit design *** of its importance,it has been fully studied in the past *** addition,the density of modern VLSI chips has increased *** today’s VLSI designs,there are increasingly more obstacles,such as IP blocks and pre-routed nets,these

关键词： VLSI MLXR multi-layer obstacle-avoiding X-architecture Steiner tree construction for VLSI routing tree