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science china chemistry 2018年第4期61卷 437-443页

作者： Siyu Lu Wei Ma Gan Jin qingsen Zeng Xiaolei feng Tanglue feng Hanyu Liu Sheng Meng Simon A.T.Redfern Bai Yang State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin University college of chemistry and molecular engineering Zhengzhou University Ningxia Key Laboratory of Photovoltaic Materials Ningxia University Geophysical Laboratory Carnegie Institution of Washington beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of Sciences department of Earth sciences University of Cambridge

As a route to improving the energy conversion of organic-inorganic hybrid-solar cells, we have tested the performance of poly(phenylene vinylene)(PPV), poly(2,5-thienylene vinylene)(PWTV) polymers and CdTe nanocrystal devices produced via aqueous-processing. It is found that small differences in the conformation of the sensitizer lead to dramatic effects on the solar cell efficiency. Using a combination of UV-Vis absorption spectroscopy and first-principles non-adiabatic molecular dynamics(NAMD) based on time-dependent density-functional theory(TDDFT), PPV is found to have a longer electron injection and recombination time despite seeming to have a better energy alignment with the substrate, which leads to a higher devices performance than PWTV. The present results shed new light on the understanding of organic-inorganic hybrid-solar cells and will trigger further experimental and theoretical investigations.

关键词： aqueous-processed polymer/CdTe charge recombination non-adiabatic molecular dynamics hybrid-solar cells

Effect of Solvophilic Chain Length in PISA Particles on Pickering Emulsion

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Chinese Journal of chemistry 2021年第12期39卷 3448-3454页

作者： Min Zeng Shuo zhou Xiaofeng Sui Jinying Yuan Key Lab of Organic Optoelectronics and molecular engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China Key Lab of science and Technology of Eco-textile Ministry of EducationCollege of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai 201620China

The morphology of polymeric nanoparticles prepared by polymerization-induced self-assembly(PISA)is depended on the degree of polymerization of the solvophilic and solvophobic ***,a series of poly(N,N-dimethylaminoethyl methacrylate)-b-poly(benzyl methacrylate)(PDMA-b-PBzMA)diblock copolymer spherical nanoparticles were synthesized via reversible addition-frag-mentation chain transfer(RAFT)mediated *** diblock copolymer nanoparticles are with nearly the same hydrodynamic size and solvophobic chain length,but with different solvophilic chain *** used these nanoparticles to stabilize the oil-in-water Pickering *** find that the stability of Pickering emulsion increases with the length of solvophilic chain of the ***,the droplet size of the Pickering emulsion can be tailored by varying the oil/water ratio and concentration of nanoparticles.

关键词： Pickering emulsion polymerization-induced self-assembly polymerization Block copolymer Nanoparticles

SiO2 stabilizes electrochemically active nitrogen in few-layer carbon electrodes of extraordinary capacitance

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Journal of Energy chemistry 2020年第10期29卷 179-188页

作者： feng Xu Tianquan Lin Jian Huang I-Wei Chen Fuqiang Huang State Key Laboratory of High Performance Ceramics and Superfine Microstructure.Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China university of Chinese Academy of sciences 19 Yuquan RoadBeijing 100049China department of Materials science and engineering University of PennsylvaniaPhiladelphiaPA 19104USA college of chemistry and molecular engineering Peking UniversityBeijing 100871China

Pyrrolic and pyridinic N dopants can dramatically increase the electrochemical activities of carbon and conducting *** N-doped conducting polymers suffer from rapid degradation,their carbon counterpart of extraordinary capacitance has remarkable rate performance and cycling endurance thanks to carbon’s excellent electrical *** high nitrogen content and high electrical conductivity are difficult to achieve in a high-surface-area carbon,because the high chemical vapor deposition(CVD)temperature required for obtaining high conductivity also destabilizes under-coordinated pyrrolic and pyridinic nitrogen and tends to lower the surface *** we resolve this dilemma by using SiO2 as an effective N-fixation additive,which stabilizes the N-rich nano few-layer sp2-carbon construct in1000℃*** enables a scalable sol-gel/CVD fabrication process for few-layer carbon electrodes of extraordinary capacitance(690 F g^-1).The electrodes have excellent rate performance and can maintain90%of their initial capacitance after 30,000 cycles,thus potentially suitable for practical applications.

关键词： Electrochemical capacitors Carbon electrodes Extraordinary capacitance SiO2 stabilized nitrogen

Electrochemical properties of niobium and phosphate doped spherical Li-rich spinel LiMn2O4 synthesized by ion implantation method

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Chinese Chemical Letters 2017年第7期28卷 1438-1446页

作者： Wei Li Gao-Wa Siqin Zhi Zhu Lu qi Wen-Huai Tian department of Materials Physics and chemistry School of Materials Science and EngineeringUniversity of Science and TechnologyBeijing 100083China New Energy Materials and Technology Laboratory Department of Applied ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Spherical Li-rich lithium manganese oxide（LMO） spinel material was synthesized by an ion implanted method assisted by polyalcohol doped with Niobium and Phosphate *** material was characterized by scanning electron microscopy,X-ray diffraction and BET specific surface area *** electrochemical performances were investigated with galvanostatic techniques and cyclic *** synthesis process was investigated with TG/*** results show that the lithium ion can be immersed into the pore of manganese dioxide at a low temperature with the ion implanted *** prepared materials have a higher discharge capacity and better crystallization than those prepared by solid phase *** doped Nb can improve the capacity of the Li-rich LMO spinel and reinforce the crystal growth along（111） and（400） *** crystal grains show circular and smooth morphology,which makes the specific surface area greatly ***-doped LMO spinel exhibits good high-rate capacity and structure *** prepared Li（1.09）Mn（1.87）Nb（0.031）O（3.99）（PO4）（0.021）delivers a discharge capacity of 119mAhg^-1 at 0.2C（1C=148mAg^-1） and 112.8 mAhg^-1 at 10 C,the discharge capacity retention reaches 98% at 1 ℃ after 50 cycles at 25 ℃ and 94% at 55 ℃.

关键词： Spinels Ion implantation Li-ion batteries LiMn2O4 Doping

Additive-Mediated Selective Oxidation of Alcohols to Esters via Synergistic Effect Using Single Cation Cobalt Catalyst Stabilized with Inorganic Ligand

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Research 2020年第1期2020卷 611-619页

作者： Jingjing Wang Han Yu Zheyu Wei qi Li Weimin Xuan Yongge Wei School of Chemical and Environmental engineering Shanghai Institute of TechnologyShanghai 201418China Key Lab of Organic Optoelectronics&molecular engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing 100191China college of chemistry Chemical Engineering and BiotechnologyDonghua UniversityShanghai 201620China

The direct catalytic oxidation of alcohols to esters is very appealing,but the economical-friendly catalysis systems are not yet well ***,we show that a pure inorganic ligand-supported single-atomic cobalt compound,(NH_(4))_(3)[CoMo_(6)O_(18)(OH)_(6)](simplified as CoMo_(6)),could be used as a heterogeneous catalyst and effectively promote this type of reaction in the presence of 30%H_(2)O_(2)using KCl as an *** oxidative cross-esterification of various alcohols(aromatic and aliphatic)could be achieved under mild conditions in nearly all cases,affording the corresponding esters in high yields,including several drug molecules and natural *** studies have revealed that chloride ion is able to bind to the CoMo_(6)to form a supramolecular dimer 2(CoMo_(6)∙Cl),which can effectively catalyze the reaction via a synergistic effect from chloride ion and CoMo_(6).Mechanism studies and control reactions demonstrate that the esterification proceeds via the key oxidative immediate of aldehydes.

关键词： oxidative alcohols esters

Ring-opening polymerization of 2-Oxabicyclo[2.2.2]octan-3-one and the Influence of Stereochemistry on the Thermal Properties of the Polyesters

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Chinese Journal of polymer science 2022年第10期40卷 1173-1182,I0008页

作者： Tong zhou Yu-Ting Guo Fu-Sheng Du Zi-Chen Li beijing National Laboratory for molecular sciences(BNLMS) Key Laboratory of Polym.Chem.&Physics of Ministry of EducationDepartment of Polymer Science&EngineeringCollege of Chemistry and Molecular EngineeringCenter for Soft Matter Science and EngineeringPeking UniversityBeijing 100871China

Polyesters with cyclic structures in the main chain typically possess superior mechanical and thermal properties together with chemical ***-opening polymerization(ROP)of bridged or fused bicyclic lactones is a simple,and in most cases controlled method to synthesize polyesters with alicyclic moieties in the polymer *** stereochemistry of the alicyclic structures has a great effect on the polymer properties,which can be regulated by varying the polymerization ***,we report a systematic investigation on the ROP of 2-oxabicyclo[2.2.2]octan-3-one([2.2.2]VL)under different *** initiated byn-butyl lithium(n-BuLi)or catalyzed by trifluoromethanesulfonic acid(TfOH)in the presence of benzyl alcohol,P[2.2.2]VLs containing all cis^(-1),4 disubstituted cyclohexane ring were ***,P[2.2.2]VLs initiated by sodium methoxide(MeONa)or catalyzed by organic superbase contained both cis and trans isomeric structural *** cis to trans transformation mechanism under these conditions was manifested,and the effect of stereochemical variations on the properties ofP[2.2.2]VLwas *** stereoregularP[2.2.2]VLs,bothcisandtrans,exhibited higher crystallinity and melting temperatures(Tm)than those of the stereoirregular ***,the degradation of P[2.2.2]VL with acid at high temperature could recover 3-cyclohexenecarboxylic acid.

关键词： 2-Oxabicyclo[2.2.2]octan-3-one Ring-opening polymerization Stereochemistry Polyester Thermal properties

"Solid-Liquid" Vitrimers Based on Dynamic Boronic Ester Networks

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Chinese Journal of polymer science 2021年第10期39卷 1292-1298,I0006页

作者： Sheng Wang Lu-Lu Xue Xiao-Zhuang zhou Jia-Xi Cui INM-Leibniz Institute for New Materials Campus D22 Saarbrucken 66123Germany beijing National Laboratory for molecular sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Institute of Fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 610054China

The"solid-liquid"behavior of vitrimers have not been systematically ***,a series of"solid-liquid"vitrimers bearing varying contents of dynamic boronic ester bonds were synthesized via thiol-ene click *** vitrimers allow for flexibile modulation of their network structures and thus show a range of intriguing properties including high stretchability,flexible transition from elasticity to plasticity,strong strain rate dependence,and solid-liquid *** dynamic association rate of boronic ester bonds within these vitrimers could be apparently accelerated via increasing the content of boronic ester,which could be used to shape-program the flat vitrimer films into various complex 3D structures just with external *** with such versatile dynamic behavior may open up a range of new applications.

关键词： Solid-liquid Dynamic covalent bond Boronic ester bond Strain-rate dependent High stretchability

氢键构筑的甲壳型液晶高分子的设计合成和自组装

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高分子学报 2023年第10期54卷 1555-1567页

作者：刘赟杨世楚沈志豪范星河周其凤北京分子科学国家研究中心、高分子化学与物理教育部重点实验室、北京大学软物质科学与工程中心、化学与分子工程学院北京100871

通过引入氢键的方法,以聚(4-乙烯基吡啶)(P4VP)为氢键受体、含羧基的小分子为氢键给体,构筑了一类新结构的超分子甲壳型液晶高分子(MJLCP).利用傅里叶红外光谱(FTIR)、广角X射线散射等表征手段证明了氢键的形成,并系统研究了小分子的化... 详细信息

通过引入氢键的方法,以聚(4-乙烯基吡啶)(P4VP)为氢键受体、含羧基的小分子为氢键给体,构筑了一类新结构的超分子甲壳型液晶高分子(MJLCP).利用傅里叶红外光谱(FTIR)、广角X射线散射等表征手段证明了氢键的形成,并系统研究了小分子的化学结构对超分子型MJLCPs液晶相行为的影响.结果表明,由于结构中只含1个(8MP)和3个苯环(4TP、6TP)且烷基尾链较短的氢键给体小分子在与P4VP复合时的“甲壳”效应较弱,P4VP(4TP)_(x)、P4VP(6TP)_(x)和P4VP(8MP)_(x)3类复合物在复合比例_(x)=1.0时仍处于无序状态.而尺寸更大的小分子氢键复合物P4VP(8TP)_(x)、P4VP(10TP)_(x)、P4VP(12MP)_(x)和P4VP(16MP)_(x)则随着复合比例的增加可以出现从无定形态向近晶(Sm)相结构的转变,并且随着烷基尾链长度和小分子刚性的增加,出现液晶相的最低复合比例逐渐减小.对于P4VP(12TP)_(x)这类氢键给体分子刚性较强且具有长烷基尾链的复合物,P4VP链在更高的复合比例下,为了容纳更多的小分子,还发生了从Sm相到六方柱状(Colh)相的结构转变.然而,氢键给体分子过大会阻碍氢键的形成,P4VP(8PP)_(x)在复合比例很低时出现了宏观相分离现象.氢键的引入大大简化了MJLCPs的构筑方法,通过对小分子化学结构和复合比例的控制可以实现对液晶相结构的灵活调控,为具有复杂结构的MJLCPs的分子设计提供了新的思路.

关键词：甲壳型液晶高分子氢键超分子液晶自组装

An amino acid-based gelator for injectable and multi-responsive hydrogel

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Chinese Chemical Letters 2017年第11期28卷 2125-2128页

作者： Wei Xiong Hantao zhou Chong Zhang Hua Lu beijing National Laboratory for molecular sciences Center for Soft Matter Science and Engineering Key Laboratory of Polymer Chemistry and Physics of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Hydrogels formed by gelators have attracted growing attention for their promising application in biomaterials and biotechnology, We describe in this paper the generation and characterization of a novel photo-, thermal- and pH-responsive hydrogel based on an amino acid gelator AA-Azo-EG6. Specifically, the gelator bears an amino acid head, an azobenzene （Azo） linker, and a short oligoethylene glycol tail （EG6）. The resulting AA-Azo-EG6 hydrogel is injectable and exhibits interesting helical self-assembled structures, Meanwhile, the hydrogel is able to experience a gel-sol or gel-precipitate phase transition responding to external stimuli. Thus, this AA-Azo-EG6 gelator is a promising building block for intelligent materials and drug delivery.

关键词： Multi-responsive Injectable Amino acid Gelator Hydrogel

Systematic Investigation of Solution-State Aggregation Effect on Electrical Conductivity in Doped Conjugated polymers

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CCS chemistry 2021年第10期3卷 2994-3004页

作者： Yang-Yang zhou Zi-Yuan Wang Ze-Fan Yao Zi-Di Yu Yang Lu Xin-Yi Wang Yi Liu qi-Yi Li Lin Zou Jie-Yu Wang Jian Pei beijing National Laboratory for molecular sciences(BNLMS) Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter of Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871 college of chemistry Shandong Normal UniversityJinan 250014 Institute of Nuclear Physics and chemistry China Academy of Engineering PhysicsMianyang 621999

The mesoscopic solution-state aggregation plays a dominant role in the multilevel self-assembly of conjugated ***,its effect on solid-state microstructures and the electrical performance of conjugated polymers is still a puzzle due to the limitation of characterization ***,we have developed four isoindigo-based conjugated polymers with varied alkyl chains to reveal the relationship between solution-state aggregation,molecular doping process,and charge transport properties.

关键词： properties. conjugated aggregation