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Science China Chemistry 2017年第9期60卷 1243-1249页

作者： Honghua Zhang Ruixia Liu Ruirui Zhang Feng Huo Zhiqiang Yang Bin He Suojiang Zhang Yanji Wang School of Chemical Engineering Hebei University of Technology Key Laboratory of Green Process and Engineering Beijing Key Laboratory of Ionic Liquids Clean ProcessState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of Sciences

Ionic liquid coupled with strong acid systems presents considerable promise in some catalytic fields. In the present work, the multiple complex systems composed by 98 wt% concentrated sulfuric acid and [Bmim][SbF6] were investigated in the terms of stability, acidity and interaction properties. It was found that acidolysis of [Bmim][SbF6] occurred in the 98 wt% concentrated sulfuric acid accompanied by HF releasing and SbF6−degrading to [SbF6−y(HSO4)y]−. The species after acidolysis in the multiple complex systems were checked and confirmed by electrospray ionization mass spectrometry (ESI-MS), Fourier transform infrared spectroscopy (FT-IR),1H NMR and19F NMR. Acidity increased slightly with less than 1 wt% [Bmim][SbF6] addition, while decreased with more proportion, which was determined based on the Hammett acidity functions H0, using13C NMR. The strong hydrogen bond S–O–HF of interaction among the multiple complex systems was confirmed by molecular dynamic simulation. © 2017, Science China Press and Springer-Verlag Berlin Heidelberg.

关键词： Electrodeposition Electrospray ionization Fourier transform infrared spectroscopy hydrogen bonds Ionic liquids Mass spectrometry Molecular dynamics Sulfuric acid

Pyridine terminated polyurethane dendrimer/chlorinated butyl rubber nanocomposites with excellent mechanical and damping properties

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Chinese Journal of Chemical Engineering 2023年第1期53卷 211-221页

作者： Jiacheng Chen Jincheng Wang Shuhong Li Kailing Xiang Shiqiang Song College of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620China

Due to the special viscoelastic property, traditional rubber with high performance has been widely used in human life and production. However, it is challenging to improve the damping property without sacrificing the extensibility. In this work, a novel type of second-generation polyurethane dendrimer terminated with pyridine(G2-Py) was synthesized by using thiolactone chemistry and subsequently complexed with Zn ions. The structure and morphology of G2-Py were characterized. G2-Py-Zn2+was then mixed with chlorinated butyl rubber(CIIR) by a two-roll mill. A series of CIIR/G2-Py-Zn2+elastomers were obtained through vulcanization. CIIR/G2-Py-Zn2+elastomers could achieve high stretchability(a strain of ~1035%), high mechanical strength(a tensile stress of 7.64 MPa). This was benefitted from the friction between G2-Py and CIIR as well as variety of non-covalent bonds provided by G2-Py-Zn2+,which can dissipate energy to further improve the strength and extensibility. The coordination of Zn2+-pyridine was confirmed by Fourier transform infrared spectroscopy, stress relaxation and cycle tensile test. To further investigate the morphology and damping properties of the elastomers, scanning electron microscopy and dynamic mechanical analysis were performed. CIIR-5 showed the best damping performance with higher tan δ_(max) and wider effective damping temperatures. Therefore, this dendrimer modification technology provides wider applications for CIIR elastomers in daily life.

关键词： Coordination bonds hydrogen bonds Polyurethane dendrimer Nanostructure Polymers Composites

Synthesis, Structure and Theoretical Calculation of Imidazolium 3,5-Dinitrobenzoate

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Chinese Journal of Structural Chemistry 2007年第12期26卷 1423-1428页

作者：王子梁魏林恒金邻豫王敬平 Institute of Molecule and Crystal Engineering College of Chemistry and Chemical Engineering Henan University College of Environment and Planning Henan University

The title adduct imidazolium 3,5-dinitrobenzoate has been synthesized in aqueous solution and characterized by elemental analyses, IR spectrum and X-ray crystallography. The title compound belongs to monoclinic, space group P21/n with a = 7.5540（9）, b = 21.333（2）, c = 7.7823（9）A, β = 102.741（2）^o, C10H8N4O6, Mr = 280.20, V= 1223.3（2）A^3, Z = 4, Dc = 1.521 g/cm^3, F（000） = 576, p = 0.129 mm^-1, the final R = 0.0433 and wR = 0.1092 for 2001 observed reflections with I 〉 2a（I）. The structural analysis indicates the component ions are linked by N-H...O hydrogen bonds into an infinite one-dimensional C2^2 （8） chain parallel to the [1 0 -1] direction. Moreover, the theoretical investigations of the title compound with HF/6-31G（d） method were performed, and its stability, frontier molecular orbital composition and Mulliken charge distribution were also discussed.

关键词： imidazole 3,5-dinitrobenzoic acid crystal structure hydrogen bonds theoretical calculation mulliken

The effect of different layered materials on the tribological properties of PTFE composites

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Friction 2020年第3期8卷 542-552页

作者： Song LI Chunjian DUAN Xiao LI Mingchao SHAO Chunhui QU Di ZHANG Qihua WANG Tingmei WANG Xinrui ZHANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy ofSciences Beijing 100049China

Two-dimensional(2D)lamellar materials have unique molecular structures and mechanical properties,among which molybdenum disulfide(MoS2)and graphitic carbon nitride(g-C3N4)with different interaction forces served as reinforcing phase for polytetrafluoroethylene(PTFE)composites in the present *** stability,tribological and thermomechanical properties of composites were comprehensively *** was demonstrated that g-C3N4 improved elastic deformation resistance and thermal degradation *** addition of g-C3N4 significantly enhanced anti-wear performance under different loads and *** results indicated that PTFE composites reinforced by g-C3N4 were provided with better properties because the bonding strength of g-C3N4 derived from hydrogen bonds(H-bonds)was stronger than that of MoS2 with van der Waals ***,g-C3N4 exhibited better thermomechanical and tribological *** result of this work is expected to provide a new kind of functional filler for enhancing the tribological properties of polymer composites.

关键词： graphitic carbon nitride lamellar materials hydrogen bonds wear resistance

Stable water droplets on composite structures formed by embedded water into fully hydroxylated β-cristobalite silica

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Chinese Physics B 2021年第1期30卷 191-196页

作者： Hanqi Gong Chonghai Qi Junwei Yang Jige Chen Xiaoling Lei Liang Zhao Chunlei Wang Division of Interfacial Water and Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Physics Shandong UniversityJinan 250100China School of Arts and Sciences Shanghai Dianji UniversityShanghai 201306China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Department of Physics East China University of Science and TechnologyShanghai 200237China College of Physical Science and Technology Yangzhou UniversityJiangsu 225009China

Using molecular dynamics simulations, we have revealed a novel wetting phenomenon with a droplet on composite structures formed by embedded water into(111) surface of β-cristobalite hydroxylated silica. This can be attributed to the formation of a composite structure composed of embedded water molecules and the surface hydroxyl(–OH) groups,which reduces the number of hydrogen bonds between the composite structure and the water droplet above the composite structure. Interestingly, a small uniform strain(±3%) applied to the crystal lattice of the hydroxylated silica surface can result in a notable change of the contact angles(> 40°) on the surface. The finding provides new insights into the correlation between the molecular-scale interfacial water structures and the macroscopic wettability of the hydroxylated silica surface.

关键词： lattice strain surface wettability embedded water hydrogen bonds

Room-temperature Self-healing and Recyclable PDMS Elastomers with Superior Mechanical Properties for Triboelectric Nanogenerators

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Chinese Journal of Polymer Science 2024年第10期42卷 1566-1577,I0014页

作者： Shu-Juan Wang Lu Wang Hong-Zhe Su Zhi-Cheng Wu Qiao-Gen Zhang Wei Fan Xin-Li Jing School of Chemistry Joint Innovation Center of Thermal Protection MaterialsXi’an Jiaotong UniversityXi’an710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an710049China School of Textile Science and Engineering Xi’an Polytechnic UniversityXi’an710048China

Polydimethylsiloxane(PDMS)is an electron-withdrawing material that is widely used in triboelectric nanogenerators(TENGs).However,PDMS has poor mechanical properties after curing and is easily damaged when subjected to long-term ***,the long-term stable operation of TENGs under mechanical deformation cannot be *** this work,multiple hydrogen bonds and aromatic disulfide bonds were introduced into PDMS *** elastomers exhibited high toughness(a tensile strength of 1.91 MPa and an elongation at break of 340%),good recyclability,and room-temperature self-healing properties(healing efficiency of 96.4%in 24 h).Recyclable sandwich-like triboelectric nanogenerators with excellent electrical output performance(13.5 V)and room-temperature self-healing performance(24 h,98%recovery of self-generating performance)were prepared by utilizing the hydrogen bonding between the PDMS elastomer and *** work reported herein offers theoretical guidance and a compelling strategy for developing high-performance TENG negative friction layers.

关键词： Polydimethylsiloxane Aromatic disulfide bonds hydrogen bonds Room temperature self-healing Triboelectric nanogenerator

Stabilizing wide-bandgap halide perovskites through hydrogen bonding

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Science China Chemistry 2022年第8期65卷 1650-1660页

作者： Lei Tao Xiaoqin Du Jianfei Hu Shixuan Wang Chen Lin Qi Wei Yingdong Xia Guichuan Xing Yonghua Chen Key Laboratory of Flexible Electronics(KLOFE)&Institution of Advanced Materials(IAM) Nanjing Tech University(Nanjing Tech)Nanjing 211816China Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials Engineering University of MacaoMacao SAR 999078China

Wide-bandgap(WBG)perovskites have emerged as promising materials for the construction of perovskite/silicon tandem solar ***,poor long-term operational stability due to the notorious photo-induced halide segregation is commonly ***,we report the synthesis of stable~1.73 eV MA-based mixed I/Br WBG perovskites by ionic liquid solvent,methylammonium acetate(MAAc).The special internal hydrogen bond(N–H…I and N–H…Br)environment in the ionic liquid MAAc solvent over traditional N,N-dimethylformamide/dimethyl sulfoxide solvent stabilizes the diffusion of halide *** allows the suppression of the halide segregation in the mixed I/Br WBG perovskite film,which is previously suggested to be *** hydrogen bonds also enable excellent decoupling of the crystal nucleation and growth ***,a champion device efficiency of 20.59%is achieved,which is one of the highest reports,with improved ambient air,heat,and light stability.

关键词： wide-bandgap perovskite hydrogen bonds perovskite solar cells ionic liquid

Synthesis and Crystal Structure of a New Glycinato Copper Compound

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Chinese Journal of Structural Chemistry 2006年第5期25卷 631-635页

作者： XIANG Sheng-Chang SHENG Tian-Lu FU Rui-Biao HU Sheng-Min WU Xin-Tao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A glycinato copper compound {Cu（NH2CH2COO）（H2O）ClO4} crystallizes in monoclinic, space group P21/n with a = 7.8299（9）, b = 10.3807（10）, c = 9.4775（12）A, β = 109.659（6）°, V = 725.43（12）A^3, Z = 4, Mr = 255.07, Dc = 2.335 g/cm^3, F（000） = 508,μ = 3.381 mm^-1, R = 0.0270 and wR = 0.0707 for 1677 observed reflections with Ⅰ 〉 2σ（Ⅰ）. The title compound contains a chain in the syn-anti conformation, which is generated by the glide-plane operation. The adjacent layers made up of the chains through the connection of perchlorate are related by inversion center operation, which links with each other through the hydrogen bonds.

关键词： glycinato copper complex chain hydrogen bonds

Azobenzene/graphene hybrid for high-density solar thermal storage by optimizing molecular structure

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Science China(Technological Sciences) 2016年第9期59卷 1383-1390页

作者： LI Man[[ FENG YiYu[[ LIU EnZuo QIN ChengQun[[ FENG Wei[[ School of Materials Science and Engineering Tianjin University Tianjin 300072 China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China Key Laboratory of Advanced Ceramics and Machining Technology Ministry of Education Tianjin 300072 China Tianjin Key Laboratory of Composite and Functional Materials Tianjin 300072 China

A large capacity storing solar energy as latent heat in a close-cycle is essentially important for solar thermal fuels. This paper presents a solar thermal molecule model of a photo-isomerizable azobenzene(Azo) molecule covalently bound to graphene. The storage capacity of the Azo depending on isomerization enthalpy(ΔH) is calculated based on density functional theory. The result indicates that the ΔH of Azo molecules on the graphene can be tuned by electronic interaction, steric hindrance and molecular hydrogen bonds(H-bonds). Azo with the withdrawing group on the ortho-position of the free benzene shows a relatively high ΔH due to resonance effect. Moreover, the H-bonds on the trans-isomer largely increase ΔH because they stabilize the trans-isomer at a low energy. 2-hydroxy-4-carboxyl-2′,6′,-dimethylamino-Azo/graphene shows the maximum ΔH up to 1.871 e V(107.14 Wh kg^(-1)), which is 125.4% higher than Azo without functional groups. The Azo/graphene model can be used for developing high-density solar thermal storage materials by controlling molecular interaction.

关键词： solar thermal energy storage azobenzene graphene hydrogen bonds density functional theory