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Rare Metals 2022年第12期41卷 4104-4115页

作者： Ye-Mao Lin Hao-Sen Fan cai-zhen zhu Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China College of Materials Science and Metallurgy Engineering Guizhou UniversityGuiyang 550025China

Owning to the wide distribution,low cost,and similar chemical-electrochemical properties with lithium,sodium-ion batteries(SIBs) have attracted much attention during recent years and may have the potential to replace the commercial lithium-ion ***,facile and simple bottom-up approach has been rationally applied to fabricate carbon-encapsulated ZnSe@CoSe_(2)micro spheres and Cu_(2)Se@CoSe_(2)*** as-prepared ZnSe@-CoSe_(2)microspheres and Cu_(2)Se@CoSe_(2)nanocubes composites inherited the original structure of ZnCo-MOF and CuCo-MOF,***,both ZnSe@CoSe_(2)micro spheres and Cu_(2)Se@CoSe_(2)nanocubes delivered excellent electrochemical performance when presented as anode materials for *** ZnSe@CoSe2micro spheres and Cu_(2)Se@CoSe_(2)nanocubes electrode could display a long-term cycling stability with a reversible capacity of 525 and 423 mAh·g^(-1)at the current density of 1 A·g^(-1)after 500 cycles,***,even at a high current density of 5 A·g^(-1),ZnSe@CoSe_(2)microsphere could still maintain 520 mAh·g^(-1)after 500 cycles,demonstrating remarkable capacity and excellent cycling *** high performances were beneficial from the unique hollow and porous structure of ZnSe@CoSe_(2)microspheres and Cu_(2)Se@CoSe_(2)nanocubes derived from the precursor which facilitate the transport of sodium ions,contributing to high capacity,improved excellent cycle stability and rate capability.

关键词： Metal selenides Prussian blue analogue Sodium-ion batteries Metal-organic frameworks(MOF)

Novel Quasi Solid-State Succinonitrile-based Electrolyte with Low-flammability for Lithium-ion Battery

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Chinese Journal of Polymer Science 2023年第11期41卷 1695-1705,I0005页

作者： Yan-Kun Xie Lu-Kun Feng Dong-Dong Li Yin Tang cai-zhen zhu Ming-Liang Wang Jian Xu Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China

Quasi solid-state succinonitrile(SN)-based polymer electrolytes have emerged for lithium-metal batteries due to their excellent ionconductivity at room temperature,wide electrochemical stability window(ESW,usually>5 V).However,the practical application of these solid SN-based polymer electrolytes is hampered by the flammability and the inherent instability of SN to Li-metal *** this work,solid SN-based polymer electrolytes were prepared with succinonitrile,ethoxylated trimethylolpropane triacrylate(ETPTA),triethyl phosphate(TEP)and fluoroethylene carbonate for Li-metal battery via in situ polymerization *** SN-based polymer electrolytes with 5 wt%triethyl phosphate and FEC showed good nonflammability,superior ion-conductivity as high as 1.01×10^(-3)S/cm,and wide ESW of 5.41 *** SN-based polymer electrolyte also exhibited excellent interfacial compatibility to lithium metal *** it also delivered a high specific capacity of 156m Ah/g at 0.2 C at ambient temperature,and presented stable cycling at 1.0 C with a specific capacity retention of 98.4%after 1000 *** work provides an alternative and simple strategy to realize the practical application of the solid-state SN-based polymer electrolyte.

关键词： Solid polymer electrolyte Succinonitrile Solid-state battery In situ polymerization Low-flammability

High-Performance Recyclable Furan-based Epoxy Resin and Its Carbon Fiber Composites with Dense Hydrogen Bonding

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Chinese Journal of Polymer Science 2024年第1期42卷 73-86,I0008页

作者： Chang-Bo Zhao Lu-Kun Feng Hui Xie Ming-Liang Wang Bing Guo Zhi-Yong Xue cai-zhen zhu Jian Xu Advanced Materials Research Institute North China Electric Power UniversityBejing 102206China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology and Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive ApplicationHarbin Institute of TechnologyShenzhen 518055China

The emerging biomass-based epoxy vitrimers hold great potential to fulfill the requirements for sustainable development of *** the existence of dynamic chemical bonds in vitrimers often reduces both the thermal and mechanical properties of epoxy resins, it is challenging to produce recyclable epoxy vitrimers with both excellent mechanical properties and good thermal stability. Herein, a monomer 4-(((5-(hydroxymethyl)furan-2-yl)methylene)amino)phenol(FCN) containing furan ring with potential to form high density of hydrogen bonding among repeating units is designed and copolymerized with glycerol triglycidyl ether to yield epoxy resin(FCN-GTE), which intrinsically has dual hydrogen bond networks, dynamic imine structure and resultant high performance. Importantly, as compared to the BPA-GTE, the FCN-GTE exhibits significantly improved mechanical properties owing to the increased density of hydrogen bond network and physical crosslinking interaction. Furthermore, density functional theory(DFT) calculation and in situ FTIR analysis is conducted to decipher the formation mechanism of hydrogen bond network. In addition, the FCN-GTE possesses superior UV shielding, chemical degradation, and recyclability because of the existence of abundant imine bonds. Notably, the FCN-GTE-based carbon fiber composites could be completely recycled in an amine *** study provides a facile strategy for synthesizing recyclable biomass-based high-performance epoxy vitrimers and carbon fiber composites.

关键词： Furan Hydrogen bond network Dynamic Schiff base Carbon fiber composites Recycling

Long-term Thermo-oxidative Degradation Modeling of a Carbon Fiber Reinforced Polyimide Composite:Multistep Degradation Behaviors and Kinetics

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Chinese Journal of Polymer Science 2020年第11期38卷 1202-1213,I0007页

作者： Yi Liu Xiao-Zhou Xu Song Mo Bang-Wei Lan cai-zhen zhu Cui-Hua Li Jian Xu Lin Fan Institute of Low-dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China Laboratory of Advanced Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

This study aims to disclose the thermo-oxidative degradation behaviors and kinetics of a carbon fiber reinforced polyimide(CFRPI)composite for modeling of the Iong-term degradation *** degradation behaviors were revealed through off-gas products analysis,and the overall kinetic interpretation was achieved from study of the mass-loss curves recorded under dynamic *** was found that thermooxidative degradati on of the CFRPI composite was a multistep process,which in eluded four main reaction *** most kinetic an alysis methods were derived from simple reactions described by a single kinetic triplet,they cannot be applied reliably to such a ***,we firstly separated the four overlapped reaction steps by peak fitting of derivative thermogravimetric curves using Fraser-Suzuki equation consider!ng the asymmetrical n ature of kin etic curves,and subsequently an a lyzed each in dividual reaction employing Friedma n method and experimental master-plots *** sets of kinetic triplets were determined to characterize the entire degradation *** validity of four corresponding kinetic triplets was confirmed by perfect simulation of mass-loss curves recorded at both dynamic conditions used in kinetic analysis and entirely different isothermal ***,modeling of Iong-term aging at 400°C of the CFRPI composite was successfully achieved based on these kinetic *** predicted mass loss and flexural property correlated well with experimental *** study can serve as a basis for rapid evaluation of the long-term durability of the CFRPI composite in various application environments.

关键词： Polyimide composite Thermo-oxidative degradation Multistep process Kinetics Long-term aging modeling

2D SAXS/WAXD ANALYSIS OF PAN CARBON FIBER MICROSTRUCTURE IN ORGANIC/INORGANIC TRANSFORMATION

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Chinese Journal of Polymer Science 2013年第5期31卷 823-832页

作者： cai-zhen zhu Xiao-lan Yu Xiao-fang Liu Yun-zen Mao Rui-gang Liu 赵宁 Xiao-li Zhang 徐坚 Beijing National Laboratory for Molecular Sciences Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of Sciences Shenzhen Key Laboratory of Functional Polymer College of Chemistry and Chemical EngineeringShenzhen University College of Materials Science and Engineering Donghua University

Structure of PAN fibers during pre-oxidation and carbonization was studied using two dimensional small angle X-ray scattering/wide angle X-ray diffraction （2D SAXS/WAXD）. The SAXS results show that during pre-oxidation between 180 ℃ and 275 ℃, the volume content of microvoids increases with the temperature increasing, which may be one of reasons for the decrease of tensile strength ofpre-oxidized fibers. 253 ℃ was the critical transition temperature, the length, diameter, aspect ratio and orientation distribution of microvoids increased with temperature before this temperature and decreased after this temperature. After the high temperature carbonization, lots of spindly microvoids formed. WAXD patterns demonstrate that the crystallite size of PAN fibers first increased before 230 ℃ and then decreased with the increase of temperature during the pre-oxidation. The diffraction peak of PAN fibers at 2θ ≈ 17°almost disappeared at the end of pre- oxidation while the diffraction peak of aromatic structure at 2θ ≈ 25° appeared at 253 ℃. During carbonization, the peak intensity at 2θ ≈ 25° increased apparently due to the formation of graphite structure. The results obtained give a deep understanding of the microstrncture development in the PAN fibers during pre-oxidation and carbonization, which is important for the preparation of high performance carbon fibers.

关键词： Polyacrylonitrile Pre-oxidation Carbonization SAXS/WAXD Microstructure.

Molecular Chain Flexibility and Dielectric Loss at High-Frequency:Impact of Ester Bond Arrangement in Poly(ester imide)s

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Chinese Journal of Polymer Science 2024年第8期42卷 1122-1133页

作者： Ya-Dong Li Hong Li Lu-Kun Feng Feng Bao Ming-Liang Wang cai-zhen zhu Zhao-Hui zheng Xiao-Bin Ding Jian Xu Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100081China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China

The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer ***,it has been theorized that rigid molecular chains lead to lower dielectric ***,the validity of this proposition at high frequencies remains *** scrutinize the correlation between chain flexibility and dielectric properties,we synthesized six poly(ester imide)s(PEIs)with systematically varied molecular chain flexibilities by modifying the ester's substitution on the aromatic *** introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor(D_(f)),ranging from 0.0021 to 0.0038 at 10 GHz in dry *** dry D_(f)displayed a pattern consistent with volume polarizability(P/V).Unexpectedly,PI-mmm-T,featu ring the most flexible molecular chain,exhibited the lowest dielectric loss under both dry(0.0021@10 GHz)and hygroscopic(0.0029@10 GHz)***,the observed increase in D_(f)after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic *** simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains,after close stacking,impede the entry of water *** sacrificing high-temperature resistance,the precursor exhibited enhanced solubility properties and could be processed into high-quality *** research unveils new insights into the relationship between flexibility and highfrequency dielectric loss,offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties.

关键词： 5G communications Poly(ester imide)s Molecular chain flexibility Dielectric properties Humidity absorption

Wireless Autonomous Soft Crawlers for Adjustable Climbing Actuation

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Chinese Journal of Polymer Science 2023年第3期41卷 405-413,I0008页

作者： Lei Tian Ji-Ji Tan Wei-Liang Dong Bo Yang Cui-Hua Li Dai Wang Hai-Yu Huang Xin-Tong Li cai-zhen zhu Jian Xu Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China

Artificial soft actuators,featured with non-equilibrium internal circumstance and fast,programmable shape transformations,have attracted strong research interest recently due to their flexibility,highly controllable,and ***,wireless soft actuators,achieving the locomotion on different large slopes with multiple energy conversion,have been rarely ***,we create a asymmetric bilayer strategy to construct autonomous soft crawler via“breathing”moisture to motivate the mechanical *** soft crawlers present conspicuous performances including periodic tumbler locomotion predicted via improved Timoshenko’s equation,multiple reversible shape-morphing(circle,helix,despiralization,etc.)determined by their fiber orientation,controlled drive mode(front drive and rear drive)and rapid climb speed(4.76 cm/min)at wide slope *** architecture design,they can be series-wound or shunt-wound to construct multijoint complex *** climbing,a intelligent soft ring-pull with admirable cycle performance for preventing overheating or something untouchable,has been *** soft crawlers also realize multiple energy conversion to be actuated by light *** envision that this soft crawler system has an enormous potential in intelligent machine,microscopic diagnosis and treatment,biosensing,energy harvesting and conversion.

关键词： Soft crawler Tumbler locomotion Reversible shape-morphing Autonomous Energy conversion

Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-Zhi Lin Lu-Kun Feng Ya-Dong Li Chao-Fan Chang cai-zhen zhu Ming-Liang Wang Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT

Wafer‑Scale Ag_(2)S‑Based Memristive Crossbar Arrays with Ultra‑Low Switching‑Energies Reaching Biological Synapses

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Nano-Micro Letters 2025年第3期17卷 328-339页

作者： Yuan zhu Tomas Nyberg Leif Nyholm Daniel Primetzhofer Xun Shi zhen Zhang Division of Solid‑State Electronics Department of Electrical EngineeringUppsala University75121 UppsalaSweden Department of Chemistry Uppsala UniversityUppsalaSweden Department of Physics and Astronomy Uppsala UniversityUppsalaSweden State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China

Memristive crossbar arrays(MCAs)offer parallel data storage and processing for energy-efficient neuromorphic ***,most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor(CMOS)technology still suffer from substantially larger energy consumption than biological synapses,due to the slow kinetics of forming conductive paths inside the memristive *** we report wafer-scale Ag_(2)S-based MCAs realized using CMOS-compatible processes at temperatures below 160℃.Ag_(2)S electrolytes supply highly mobile Ag+ions,and provide the Ag/Ag_(2)S interface with low silver nucleation barrier to form silver filaments at low energy *** further enhancing Ag+migration in Ag_(2)S electrolytes via microstructure modulation,the integrated memristors exhibit a record low threshold of approximately−0.1 V,and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological *** low-temperature process also enables MCA integration on polyimide substrates for applications in flexible ***,the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training *** impressive accuracy of 92.6%in image recognition simulations is demonstrated with the MCAs after the *** demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag_(2)S films Reactive sputter Silver nucleation Ag^(+)migration Energy-efficient neuromorphic computing

RE-SEGNN:recurrent semantic evidence-aware graph neural network for temporal knowledge graph forecasting

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Science China(Information Sciences) 2025年第2期68卷 103-119页

作者： Wenyu cai Mengfan LI Xuanhua SHI Yuanxin FAN Quntao zhu Hai JIN National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and Technology

Temporal knowledge graph(TKG) reasoning, has seen widespread use for modeling real-world events, particularly in extrapolation settings. Nevertheless, most previous studies are embedded models, which require both entity and relation embedding to make predictions, ignoring the semantic correlations among different entities and relations within the same timestamp. This can lead to random and nonsensical predictions when unseen entities or relations occur. Furthermore, many existing models exhibit limitations in handling highly correlated historical facts with extensive temporal depth. They often either overlook such facts or overly accentuate the relationships between recurring past occurrences and their current counterparts. Due to the dynamic nature of TKG, effectively capturing the evolving semantics between different timestamps can be *** address these shortcomings, we propose the recurrent semantic evidenceaware graph neural network(RE-SEGNN), a novel graph neural network that can learn the semantics of entities and relations simultaneously. For the former challenge, our model can predict a possible answer to missing quadruples based on semantics when facing unseen entities or relations. For the latter problem, based on an obvious established force, both the recency and frequency of semantic history tend to confer a higher reference value for the current. We use the Hawkes process to compute the semantic trend, which allows the semantics of recent facts to gain more attention than those of distant facts. Experimental results show that RE-SEGNN outperforms all SOTA models in entity prediction on 6 widely used datasets, and 5 datasets in relation prediction. Furthermore, the case study shows how our model can deal with unseen entities and relations.

关键词： knowledge graph reasoning temporal knowledge graph Hawkes process semantic evidence

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