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Impact of Carbon Chain Structures in the Backbone on the Flexibility of Modified Polyarylene Sulfide Resins: Molecular Dynamics Simulations and Mesoscopic Analysis

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Chinese Journal of Polymer Science 2024年第4期42卷 544-557页

作者： Chi Zhang Rong Liu Jing-Yuan Liu Wen-Wei Jiang Key Laboratory of fine Chemical engineering and Functional materials School of Chemical EngineeringSichuan UniversityChengdu610065China

In the domain of high-performance engineering polymers, the enhancement of mechanical flexibility in poly(phenylene sulfide) (PPS) resins has long posed a significant challenge. A novel molecular structure, designated as PP-He-IS, wherein imide rings and an aliphatic hexylene chain are covalently incorporated into the PPS backbone to enhance its flexibility, is introduced in this study. Molecular dynamics (MD) simulations are employed to systematically explore the effects of diversifying the backbone chain structures by substituting phenyl units with alkyl chains of varying lengths, referred to as PP-A-IS where “A” signifies the distinct intermediary alkyl chain configurations. Computational analyses reveal a discernable decrement in the glass transition temperature (Tg) and elastic modulus, counterbalanced by an increment in yield strength as the alkyl chain length is extended. Notably, the PP-He-IS variant is shown to exhibit superior yield strength while simultaneously maintaining reduced elastic modulus and Tg values, positioning it as an advantageous candidate for flexible PPS applications. Mesoscopic analyses further indicate that structures such as PP-He-IS, PP-Pe-IS, and PP-Bu-IS manifest remarkable flexibility, attributable to the presence of freely rotatable carbon-carbon single bonds. Experimental validation confirms that a melting temperature of 504 K which is lower than that of conventional PPS, and lower crystallinity are exhibited by PP-He-IS, thereby affording enhanced processability without compromising inherent thermal stability. Novel insights into the strategic modification of PPS for mechanical flexibility are thus furnished by this study, which also accentuates the pivotal role played by molecular dynamics simulations in spearheading high-throughput investigations in polymer material modifications.

关键词： Molecular dynamics simulations Polyarylene Sulfide Main-chain modifications Flexibility Aliphatic hexylene chain

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Ceramic-based meta-material absorber with high-temperature stability

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Rare Metals 2024年第9期43卷 4433-4440页

作者： Xing-Cong Chen Wei-Jia Luo Run-Ni Zhao Yong-Zheng Wen Ji Zhou State Key Laboratory of New Ceramics and fine Processing School of Materials Science and EngineeringTsinghua University

With the continuous exploration of uncharted and extreme environments,enhanced temperature robustness of passive devices has become particularly *** this study,a ceramic-based meta-material absorber with exceptional temperature stability is developed using a fusion design approach that combines rare metal-based tungsten bronze structural ceramics and ***,the absorbance of the meta-material array based on Mie resonance exceeds 49.0%in both waveguides and free space,approaching the theoretical *** to impedance analysis,the absorption performance can be distinctly correlated with the dielectric loss （Q_f）.Notably,the high-temperature robustness is verified to still be effective at 400℃.These advancements in our design allow for the use of monolithic materials in fabricating temperature-stable perfect absorbers,providing greater freedom in the dielectric performance and expanding their potential applications,including in space exploration and 5G millimeter-wave scenarios.

关键词： Meta-material absorber Microwave absorption Miniaturization Rare metal-based ceramics Temperature robustness

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Ten-Minute Synthesis of a New Redox-Active Aqueous Binder for Flame-Retardant Li-S Batteries

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Energy & Environmental materials 2024年第2期7卷 52-61页

作者： Tianpeng Zhang Borui Li Zihui Song Wanyuan Jiang Siyang Liu Runyue Mao Xigao Jian Fangyuan Hu School of materials Science and engineering State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart Materials Oriented Chemical Engineering Technology Innovation Center of High Performance Resin Materials (Liaoning Province) Key Laboratory of Energy Materials and Devices (Liaoning Province) Dalian University of Technology State Key Laboratory of fine Chemicals Frontiers Science Center for Smart Materials Oriented Chemical Engineering School of Chemical Engineering Technology Innovation Center of High Performance Resin Materials (Liaoning Province) Key Laboratory of Energy Materials and Devices (Liaoning Province) Dalian University of Technology

As a critical role in battery systems,polymer binders have been shown to efficiently suppress the lithium polysulfide shuttling and accommodate volume changes in recent ***,preparation processes and safety,as the key criterions for Li-S batteries' practical applications,still attract less ***,an aqueous multifunction binder（named PEI-TIC） is prepared via an easy and fast epoxy-amine ring-opening reaction（10 min）,which can not only give the sulfur cathode a stable mechanical property,a strong chemical adsorption and catalytic conversion ability,but also a fire safety *** Li-S batteries based on the PEI-TIC binder display a high discharge capacity(1297.8 mAh g-1),superior rate performance(823.0 mAh g-1at 2 C),and an ultralow capacity decay rate of 0.035% over more than 800 *** under 7.1 mg cm-2S-loaded,the PEI-TIC electrode can also achieve a high areal capacity of 7.2 mA h g-1and excellent cycling stability,confirming its application ***,it is also noted that TG-FTIR test is performed for the first time to explore the flame-retardant mechanism of polymer *** work provides an economically and environmentally friendly binder for the practical application and inspires the exploration of the flame-retardant mechanism of all electrode components.

关键词： 3D cross-linked network environmentally friendly flame retardant Li-S batteries multifunction binder

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Grain size refinement of additive manufactured Ce-TZP ceramics by coupled two-step pre-sintering and HIP

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Journal of Advanced Ceramics 2024年第5期13卷 621-629页

作者： Ruoshi Zhao Hongbing Yang Xintong Liu Hezhen Li Chang-An Wang Jing Ma Yanhao Dong State Key Lab of New Ceramics and fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Ceria-stabilized tetragonal zirconia polycrystal(Ce-TZP)has exceptional fracture toughness and flaw tolerance due to facile t‒m phase transformation ***,its wider-range applications are limited by its relatively low strength due to its large grain size and low transformation stress,which results in yield-like ***,we combined additive manufacturing(AM),pressureless two-step sintering,and hot isostatic pressing(HIP),and addressed the challenging grain size refinement problem in *** successfully produced dense ultrafine-grained Ce-TZP ceramics with an average grain size below 500 nm,a three-point bending strength above 800 MPa,and a single-edge-notch-beam fracture toughness in the range of 11‒12 MPa·m^(1/2).The critical roles of processing design,mixed Ce valences,and ***-stabilization of tetragonal polymorphs were *** work offers insights and strategies for the future development of stronger and tougher Ce-TZP ceramics that can compete with tetragonal yttria-stabilized zirconia in various applications,including additive manufacturing.

关键词： zirconia additive manufacturing(AM) two-step sintering hot isostatic pressing(HIP) grain size refinement

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3D-shaped 3D-continuously graphene cellulose(3D^(2)GC)architecture

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Nano Research 2024年第7期17卷 6695-6699页

作者： Abdelrahman Brakat Hongwei Zhu State Key Lab of New Ceramics and fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

In the endeavor to develop three-dimensional(3D)-architected sophisticated hierarchical structures,the synergy between inplane and out-of-plane interactions at interfaces offers new *** interplay,governed by van der Waals(vdW)interfacial nanoarchitectonics,facilitates the design of efficient thermally conductive *** work delves into the kinetics underlying a dual-templating strategy,seamlessly integrating two-dimensional(2D)-graphene sheets with one-dimensional(1D)-cellulose chains at heterointerfaces,thereby transforming into 3D-shaped and 3D-continuously anisotropic structures,termed as(3D^(2)GC)***,we designed and fabricated an anisotropic graphene cellulose scaffold(GCS)employing a nickel *** as-grown GCS replicates the 3D-shaped and configuration of the *** 3D-continuously interconnected fibrous-porous network of the GCS,combined with its anisotropic thermal properties(λ_(axial)/λ_(radial)),not only is promising for advanced thermal technologies but also offers advantages in cost-effectiveness and eco-effectiveness.

关键词： two-dimensional(2D)-graphene one-dimensional(1D)-cellulose heterointerface anisotropic three-dimensional(3D)-architecture

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Exceptional electrostrain with minimal hysteresis and superior temperature stability under low electric field in KNN-based lead-free piezoceramics

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Journal of Advanced Ceramics 2024年第3期13卷 364-372页

作者： Huan Liu Yijin Hao Ziqi Yang Tianyi Feng Bin Su Xin Zhang Mengping Xue Bo-Ping Zhang Jing-Feng Li Beijing Municipal Key Laboratory of New Energy materials and Technologies School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of New Ceramics and fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Over the past two decades,(K_(0.5)Na_(0.5))NbO_(3)(KNN)-based lead-free piezoelectric ceramics have made significant ***,attaining a high electrostrain with remarkable temperature stability and minimal hysteresis under low electric fields has remained a significant *** address this long-standing issue,we have employed a collaborative approach that combines defect engineering,phase engineering,and relaxation *** LKNNS-6BZH ceramic,when sintered at T_(sint)=1170℃,demonstrates an impressive electrostrain with a d_(33) value of 0.276%and 1379 pm·V^(-1)under 20 kV·cm^(-1),which is comparable to or even surpasses that of other lead-free and Pb(Zr,Ti)O_(3)***,the electrostrain performance of this ceramic remains stable up to a temperature of 125℃,with the lowest hysteresis observed at 9.73%under 40 kV·cm^(-1).These excellent overall performances are attributed to the presence of defect dipoles involving V′_(A)-V∙∙_(O) and B′_(Nb)-V∙∙O,the coexistence of R-O-T multiphase,and the tuning of the trade-off between long-range ordering and local *** work provides a lead-free alternative for piezoelectric actuators and a paradigm for designing piezoelectric materials with outstanding comprehensive performance under low electric fields.

关键词： lead-free piezoelectric ceramics temperature stability electrostrain potassium sodium niobate low hysteresis

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Highly Efficient Broadband Achromatic Microlens Design Based on Low-Dispersion materials

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engineering 2024年第7期38卷 194-200页

作者： Xueqian Wang Chuanbao Liu Feilou Wang Weijia Luo Chengdong Tao Yuxuan Hou Lijie Qiao Ji Zhou Jingbo Sun Yang Bai Beijing Advanced Innovation Center for materials Genome engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China School of materials and engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of New Ceramics and fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Metalenses with achromatic performance offer a new opportunity for high-quality imaging with an ultracompact configuration;however,they suffer from complex fabrication processes and low focusing *** this study,we propose an efficient design method for achromatic microlenses on a wavelength scale using materials with low dispersion,an adequately designed convex surface,and a thickness profile *** taking into account the absolute chromatic aberration,relative focal length shift(FLS),and numerical aperture(NA),microlens with a certain focal length can be realized through our realized map of geometric ***,the designed achromatic microlenses with low-dispersion fused silica were fabricated using a focused ion beam,and precise surface profiles were *** fabricated microlenses exhibited a high average focusing efficiency of 65%at visible wavelengths of 410-680 nm and excellent achromatic capability via white light ***,the design exhibited the advantages of being polarization-insensitive and *** results demonstrate the effectiveness of our proposed achromatic microlens design approach,which expands the prospects of miniaturized optics such as virtual and augmented reality,ultracompact microscopes,and biological endoscopy.

关键词： Broadband achromatic focusing Metamaterials Low dispersion materials Visible wavelength Microlenses

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Progresses and Prospects of Asymmetrically Coordinated Single Atom Catalysts for Lithium-Sulfur Batteries

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Energy & Environmental materials 2024年第4期7卷 48-63页

作者： Rong Zhou Shaonan Gu Meng Guo Shuzheng Xu Guowei Zhou Key Laboratory of fine Chemicals in Universities of Shandong Jinan Engineering Laboratory for Multi-scale Functional Materials School of Chemistry and Chemical Engineering Qilu University of Technology(Shandong Academy of Sciences)

Lithium-sulfur batteries (LSBs) are widely regarded as promising next-generation batteries due to their high theoretical specific capacity and low material ***,the practical applications of LSBs are limited by the shuttle effect of lithium polysulfides (LiPSs),electronic insulation of charge and discharge products,and slow LiPSs conversion reaction kinetics.

关键词： asymmetrical coordination conversion catalysis Li-S batteries shuttle effect single atom catalysts

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Solid superacid catalysts promote high-performance carbon dots with narrow-band fluorescence emission for luminescence solar concentrators

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Chinese Chemical Letters 2024年第8期35卷 437-442页

作者： Rui Cheng Xin Huang Tingting Zhang Jiazhuang Guo Jian Yu Su Chen State Key Laboratory of materials-Oriented Chemical engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China Jiangsu Key Laboratory of fine Chemicals and Functional Polymer materials Nanjing 210009China

Facile and efficient method for constructing carbon dots(CDs)with narrow full width at half maximum(FWHM)is a major challenge in the field,and researches on regulating the FWHM of CDs are also rare and *** this work,we delved into the synthesis of CDs with narrow fluorescence emission FWHM(NFEF-CDs)in the m-phenylenediamine(m-PD)/ethanol system,utilizing solid superacid resin as cata-lyst with solvothermal *** resulting NFEF-CDs exhibit a photoluminescent(PL)emission peak at 521 nm with a narrow FWHM of 41 nm,an absolute PL quantum yield(QY)of 80%,and display excitation-independent PL *** comprehensive characterization,we identified the protonation of edge amino on NFEF-CDs as the key factor in achieving the narrow ***,we validated the broad applicability of solid superacid resins as catalysts for synthesizing CDs with narrow FWHM in the m-PD/ethanol ***,we utilized a self-leveling method to prepare NFEF-CDs film on the surface of poly(methyl methacrylate)(PMMA)substrate and investigated the solid-state fluorescence properties of NFEF-CDs as well as their performance as luminescence solar concentrator(LSC)for photovoltaic *** results revealed that the as-prepared LSC exhibit an internal quantum efficiency(η_(int))of 42.39%and an optical efficiency(η_(opt))of 0.68%.These findings demonstrate the promising prospects of NFEF-CDs in the field of LSCs and provide a theoretical basis for their application in photovoltaic conversion.

关键词： Carbon dots Narrow full width at half maximum Solid-state fluorescence Luminescence solar concentrators Photovoltaic conversion

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Insights into the role of oxygen-containing functional groups on carbon surface in water–electricity generation

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Nano Research 2024年第7期17卷 6645-6653页

作者： Wan Xue Zongbin Zhao Honghui Bi Bolun Zhang Xuzhen Wang Jieshan Qiu State Key Laboratory of fine Chemicals Liaoning Key Laboratory for Energy Materials and Chemical EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China State Key Laboratory of fine Chemicals Liaoning Key Laboratory for Energy Materials and Chemical EngineeringSchool of ChemistryDalian University of TechnologyDalian 116024China State Key Laboratory of Chemical Resource engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China

A deep understanding of the electricity generation mechanism from the interaction between water molecules and carbon material surfaces is attractive for next-generation water-based energy conversion and storage ***,an asymmetric generator was assembled based on functionalized carbon nanotubes films to investigate the relative contribution from various oxygen functional groups on carbon surface to the water-electrical *** and calculations demonstrate that the electricity mainly originates from the water molecule adsorption by carboxyl groups and dissociation of functional groups on carbon surface,which leads to the formation of electrical double layers at *** device allows the electricity generation with a variety of water sources,such as deionized water,tap water,as well as *** particular,the generator based on carboxyl carbon nanotubes can induce a voltage of over 200 mV spontaneously in natural seawater with the power density of about 0.11 mW·g^(−1).High voltages can be achieved easily through the series-connection strategy to power electronic products such as a liquid crystal *** work reveals the dominant role of carboxyl groups in carbon-based water–electricity conversion and is expected to offer inspiration for the preparation of carbon materials with high electrical performance.

关键词： electricity generation water adsorption dissociation carboxyl groups carbon nanotubes

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