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Science China Chemistry 2024年第4期67卷 1137-1160页

作者： Hui-Min Xu Hong-Rui Zhu Chen-Jin Huang zhi-jie zhang Ting-Yu Shuai Qi-Ni Zhan Gao-Ren Li College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Fe-nitrogen-carbon(Fe-N-C)-and Co-nitrogen-carbon(Co-N-C)-based electrocatalysts have been widely concerned because of their high OER/ORR activity,low metal cost,and simple *** exploration of Fe-N-C and Co-N-C single atombased catalysts with high activity and stability to overcome the slow kinetics of oxygen reduction and oxygen evolution reactions is also the key to the development of efficient electrolytic water,fuel cells,and rechargeable metal-air ***-N-C and Co-N-C single atom-based electrocatalysts have the advantages of a high utilization rate of metal atoms and high electrocatalytic activity,and are ideal catalysts for promoting electrochemical energy conversion and *** general principles of designing Fe-N-C and Co-N-C single atom-based electrocatalysts are reviewed in this ***,the strategies to improve the bifunctional catalytic activity and stability are ***,the challenges and prospects of Fe-N-C and Co-N-C single atom-based catalysts are well *** review will provide a reference for the directed optimization of Fe-N-C and Co-N-C single atom-based catalysts.

关键词： Fe-N-C Co-N-C single atom bifunctional oxygen electrocatalysts

Double active sites promoting hydrogen evolution activity and stability of CoRuOH/Co_(2)P by rapid hydrolysis

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Chinese Chemical Letters 2024年第7期35卷 206-211页

作者： Bin Dong Ning Yu Qiu-Yue Wang Jing-Ke Ren Xin-Yu zhang zhi-jie zhang Ruo-Yao Fan Da-Peng Liu Yong-Ming Chai State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China

Cobalt-based phosphides show excellent hydrogen evolution reaction(HER)performance,however,improving the intrinsic activity and stability of it in alkaline electrolyte still remains a ***,CoRuOH/Co_(2)P/CF with heterojunction structure was developed by means of molten salt and rapid hydrolysis(30 s).The OH-from rapid surface hydrolysis of Co_(2)P as a hydrogen adsorption site can facilitate the formation of thin CoRuOH layer as a water dissociation site,which may bring out better synergistic effect for alkaline ***,the covering of CoRuOH can improve the stability of Co_(2)P for *** drives at 100 mA/cm^(2),it only requires overpotential of 81 mV in 1.0 mol/L KOH(25℃).Even at higher current density(1000 mA/cm^(2)),CoRuOH/Co_(2)P/CF can also operate stability for at least 100 *** coupling with NiFe-LDH/IF in a two-electrode system,the voltage of NiFe-LDH/IF(+)||CoRuOH/Co_(2)P/CF(-)at 1000 mA/cm^(2)is merely 1.77 V with 100 h,demonstrating great potential for water *** implementation of this work provides a new strategy and reference for the further improvement of transition metal phosphides as HER electrocatalysts.

关键词： CoRuOH/Co_(2)P/CF Enhanced activity and stability Double active site Large current density Hydrogen evolution reaction

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Crack elimination and strength enhancement mechanisms of selective laser melted Si-modified Al−Mn−Mg−Er−Zr alloy

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Transactions of Nonferrous Metals Society of China 2024年第8期34卷 2431-2441页

作者： Jiang YU Yao-xiang GENG Hong-bo JU zhi-jie zhang Jun-hua XU School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Department of Mechanical Engineering CEMMPRE-Centre for Mechanical Engineering Materials and ProcessesUniversity of CoimbraCoimbraPortugal

In order to increase the processability and process window of the selective laser melting(SLM)-fabricated Al−Mn−Mg−Er−Zr alloy,a novel Si-modified Al−Mn−Mg−Er−Zr alloy was *** effect of Si alloying on the surface quality,processability,microstructure,and mechanical properties of the SLM-fabricated alloy was *** results showed that introducing Si into the Al−Mn−Mg−Er−Zr alloy prevented balling and keyhole formation,refined the grain size,and reduced the solidification temperature,which eliminated cracks and increased the processability and process window of the *** maximum relative density of the SLM-fabricated Si/Al−Mn−Mg−Er−Zr alloy reached 99.6%.The yield strength and ultimate tensile strength of the alloy were(371±7)MPa and(518±6)MPa,*** values were higher than those of the SLM-fabricated Al−Mn−Mg−Er−Zr and other Sc-free Al−Mg-based alloys.

关键词： selective laser melting Al−Mn−Mg−Er−Zr−Si alloy surface roughness processability mechanical properties

Effects of Branches on the Crystallization Kinetics of Polypropylene-gPolystyrene and Polypropylene-g-Poly(n-butyl acrylate) Graft Copolymers with Well-defined Molecular Structures

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Chinese Journal of Polymer Science 2014年第3期32卷 333-349页

作者： Lu Wang zhi-wei Jiang Feng Liu zhi-jie zhang 唐涛 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences

Effects of branches on the crystallization kinetics of polypropylene-g-polystyrene （PP-g-PS） and polypropylene-g- poly（n-butyl acrylate）（PP-g-PnBA） graft copolymers with well-defined molecular structures were systematically investigated by DSC. The Avrami equation was used to analyze the isothermal crystallization process, while the analysis of nonisothermal crystallization process was based on the Jeziorny-modified Avrami model and Mo model. The kinetics results of isothermal and nonisothermal crystallization verified the peculiar effects of branches on the crystallization process of PP backbones in PP-g-PS and PP-g-PnBA graft copolymers： on one hand, the interaction between branches （n-n interaction between PS branches, or dipole-dipole interaction between PnBA branches） restrained the mobility and reptation ability of the PP backbones, which hindered the crystallization process; on the other hand, the heterogeneous nucleation effect resulting from the branched structure and fluctuation-assisted nucleation mechanism （caused by microphase separation between the PS or PnBA rich phase and the PP rich phase） became more pronounced with increasing branch length, which facilitated the crystallization process.

关键词： Polypropylene Polypropylene-g-polystyrene graft copolymer Polypropylene-g-poly(n-butyl acrylate) graftcopolymer Isothermal crystallization Nonisothermal crystallization.

Synthesis of Star-like Polybutadienes by a Combination of Living Anionic Polymerization and “Click” Coupling Method

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Chinese Journal of Polymer Science 2014年第6期32卷 731-742页

作者： Guang-chun zhang Jun Zheng Feng Liu zhi-jie zhang 马丽唐涛 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

Three-arm and four-arm star-like polybutadienes （PBds） were synthesized via the combination of living anionic polymerization and the click coupling method. Kinetic study showed that the click reaction between the azido group terminated PBd-t-N3 and the alkyne-containing multifunctional linking reagent was fast and highly efficient. All coupling reactions were fully accomplished within 40 min at 50 ℃ in toluene in the presence of the reducing agent Cu（0）, proven by 1H-NMR, FTIR and GPC measurements. For the coupling reactions between the PBd-t-N3 polymer and dialkyne-containing compound, the final conversion of the coupled PBd-PBd polymer was ca. 97.0%. When a PBd-t-N3 polymer was reacted with trialkyne-containing or tetraalkyne-containing compound, the conversion of three-arm or four-arm PBd was around 95.5% or 87.0%, respectively. Several factors influencing the coupling efficiency were studied, including the molecular weight of the initial PBd-t-N3, arm numbers and the molar ratio of the azido group to the alkynyl group. The results indicated that the conversion of the target products would be promoted when the molecular weight of the PBd-t-N3 was low and the molar ratio of the azido to alkynyl groups was close to 1.

关键词： Polybutadiene Living anionic polymerization Click chemistry Kinetic study Coupling efficiency Star-like.

Random Binary Brush Architecture Enhances both Ionic Conductivity and Mechanical Strength at Room Temperature

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Chinese Journal of Polymer Science 2018年第1期36卷 78-84页

作者： Yu-Feng Lyu zhi-jie zhang Chang Liu zhi Geng Long-Cheng Gao Quan Chen Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education School of Chemistry and EnvironmentBeihangUniversityBeijing 100191China State KeyLaboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The ionic conductivity and the mechanical strength are two key factors for the performance of poly（ethylene oxide）（PEO） based polyelectrolytes. However, crystallized PEO suppresses ion conductivity at low temperature and melted PEO has low mechanical strength at high temperature. Here, random binary brush copolymer composed of PEO-and polystyrene（PS）-based side chains is synthesized. PEO crystallinity is suppressed by the introduction of PS brushes. Doping with lithium trifluoromethanesulfonate（Li Tf） induces microphase separation. Due to a random arrangement of the brushes, the microphase segregation is incomplete even at high salt loading, which provides both high ionic conductivity and high mechanical strength at room temperature. These results provide opportunities for the design of polymeric electrolytes to be used at room temperature.

关键词： Binary brush copolymer PEO Ionic conductivity Phase separation

Silazyl-Lithiums: A kind of new Initiators for the Anionic Non- equilibrium Ring-opening Polymerization of Octamethylcyclotetrasiloxane (D_4)

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Chinese Chemical Letters 2002年第12期13卷 1174-1177页

作者： Shun Xing SU zhi jie zhang zhi Min ZHENG Ze Min XIE State Key Laboratory of Engineering Plastics Center for Molecular ScienceInstitute of Chemistrythe Chinese Academy of SciencesBeijing 100080

The initiation reactions in the anionic non-equilibrium polymerization of octamethy- lcyclotetrasiloxane (D4) initiated by silazyllithiums were investigated. It was found that the structure of the substituents on the... 详细信息

关键词： Anionic non-equilibrium polymerization polysiloxane silazyl-lithiums.

光电催化析氧和CO_(2)还原反应催化剂的研究进展

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Chinese Journal of Catalysis 2024年第7期62卷 53-107页

作者：朱鸿睿徐慧民黄陈金张志杰詹麒尼帅婷玉李高仁四川大学材料科学与工程学院四川成都610065

随着日益增加的化石能源消耗和环境污染,新能源和环境友好型技术的应用对工业发展发挥着重要作用.利用太阳能及电能进行各种催化反应的光电催化(PEC)是一种有应用前景的技术,与传统催化技术相比,具有环保节能、效率高的优势.析氧反应(O... 详细信息

随着日益增加的化石能源消耗和环境污染,新能源和环境友好型技术的应用对工业发展发挥着重要作用.利用太阳能及电能进行各种催化反应的光电催化(PEC)是一种有应用前景的技术,与传统催化技术相比,具有环保节能、效率高的优势.析氧反应(OER)和CO_(2)还原反应(CO_(2)RR)是两种具有能源及环境应用潜力的催化反应.PECOER对基于水氧化和其他相关氧化反应的可再生能源技术具有重要作用.PEC CO_(2)RR可以将CO_(2)转化为高附加值化学品,实现CO_(2)的合理利用.上述两种技术均具有较大的研究价值和应用前景.本综述首先阐述了电催化和光催化技术的优缺点.由于工业上使用电催化技术会消耗煤和石油等化石能源,有污染环境的风险,且长期的用电成本会影响最终的盈利;而使用光催化技术又面临着反应效率不理想、稳定性差和可见光吸收率低等缺点.一方面,PEC技术可以解决光催化中光生电子-空穴对复合速度快、反应时间长的缺点;另一方面,PEC技术可以降低电催化过程中在高电流密度下反应所需的过电位,在节省电能的同时提高反应效率.此外,系统地介绍了光电催化产氧和CO_(2)RR的机理和参数、催化剂类型、评价标准以及近年来的研究进展.对于反应条件,光电催化和电催化所使用的基础仪器基本相同,而光电催化是在电催化的基础之上施加外部光源,利用光能进一步提高反应效率和稳定性.光电催化和电催化的反应机理也基本一致,不同的是光电催化的评价标准与电催化有所不同.在光照作用下,除了关注特定电压下的电流密度、选择性和稳定性外,研究者们更关注应用偏压光子电流转换效率(ABPE)和入射光子对电流的效率(IPCE)的影响.同时,介绍了用于PEC OER和CO_(2)RR催化剂的类别、优势、合成方法、设计原则和改性策略.就目前研究而言,光电催化性能优异的催化剂一般都具有导电性良好、光吸收效率高和载流子分离速率快等特点.随着对光电催化技术研究地深入,通过掺杂、制造缺陷、设计异质结、负载单/双原子和改变反应微环境等方法有效地提升了催化效率和稳定性.在上述研究基础上,还扩展性地阐述光热催化、光酶催化等近几年的热点技术,这些技术均具有反应条件温和、过程简单和效率高等特点,在未来具有较大的研究价值.最后,展望了PEC技术的未来发展趋势和前景,重点关注了它在工业上的应用前景和价值.在未来,PEC技术将朝着智能化、创新和环保的方向发展.通过先进的理论技术(如理论计算、机器学习、分子动力学模拟等)和原位表征探索反应机理,实现低成本、绿色和智能化的技术以迎接未来实现大规模工业化的挑战,从而在盈利和环保两者之间实现“双赢”.希望本文能帮助读者更快及更全面地了解PEC技术的基本原理、常用催化剂、改性策略、拓展技术、应用前景和发展趋势,从而为读者提供可借鉴的研究思路.

关键词：光电催化催化剂设计催化剂制备析氧反应二氧化碳还原反应

Enhanced memristor performance via coupling effect of oxygen vacancy and ferroelectric polarization

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Journal of Materials Science & Technology 2024年第4期171卷 139-146页

作者： zhi Yun Yue zhi Dong zhang Zhan jie Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

As a new type of nonvolatile memory,the resistive memristor has broad application prospects in in-formation storage and neural computing based on its excellent resistive switching(RS)*** present,it is still a great challenge to improve both ferroelectric polarization and leakage current to achieve a high RS on/offratio of ferroelectric ***,epitaxial Pb(Zr_(0.40)Ti_(0.60))O_(3)(PZT)thin films with low content Ca doping were deposited on the Nb:SrTiO_(3)substrate to prepare PCZT/NSTO het-erostructures and their RS behaviors were *** research findings show that compared with pure PZT film,the ferroelectric polarization of 1-mol%-Ca-doped PZT film is slightly improved,while the leak-age current is increased by three orders of ***,the RS on/offratio reaches 2.5×10^(5),about three orders of magnitude higher than pure PZT *** theoretical analysis reveals that the RS behavior of PCZT/NSTO heterostructures is controlled by the PCZT/NSTO interfacial barrier and the space charge-limited current *** results demonstrate that the ferroelectricity and electricity of ferroelectric thin films can be improved simultaneously by doping low-content Ca ions to increase the RS performance,which provides a good reference for the development of high-performance ferroelectric memristor devices.

关键词： Ferroelectric memristor Ca-doped PZT Ferroelectric polarization Oxygen vacancies Resistive switching

Synthesis of Some New Derivatives of 1,3-Dichloro-1,1,3,3-tetraphenyldisilazane

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Chinese Chemical Letters 2001年第1期12卷 35-38页

作者： Cai Hong XU zhi jie zhang Yong Min LI zhi Min ZHENG Ze Min XIE Center for Molecular Science Institute of ChemistryThe Chinese Academy of SciencesBeijing 100080

The reactive properties of 1,3-dichloro-1,1,3,3-tetraphenyldisilazane (DCTPS) with water, methanol, phenylamine and lithium salt of hexamethylcyclotrisilazane (D-3(NLi)) were investigated, and four new derivatives wer... 详细信息

关键词： 1,3-dichloro-1,1,3,3-tetraphenyldisilazane derivatives reactive properties