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Hexagonal boron nitride based slippery liquid infused porous surface with anti-corrosion, anti-contaminant and anti-icing properties for protecting magnesium alloy

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Chinese Chemical Letters 2024年第4期35卷 532-538页

作者： Wenhao Yan Shuaiya Xue Xuerui Zhao Wei Zhang Jian Li key laboratory of eco-Functional polymer materials of the ministry of education College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China

In an era where the concept of green development is deeply rooted, magnesium(Mg) alloy as a light metal has a long-term development prospect in the process of energy saving, emission reduction and environmental improvement. However, anti-corrosion performance of Mg alloy is poor due to the high chemical activity and low equilibrium potential, which limits the development of Mg alloy products.Herein, three-dimensional mesopore hollow polypyrrole spheres(MHPS) were prepared, and the MHPS was inserted into the middle of the stacked hexagon boron nitride(h-BN) lamellae, which allowed the hBN to be separated forming a further composite with abundant pore structure. Subsequently, the MHPS/hBN-OH composite was uniformly sprayed on the Mg alloy surface via simple spraying method to form the superhydrophobic surface(SHS). Finally, the slippery liquid infused porous surface(SLIPS) was successfully fabricated by applying drops of silicone lubricant on the superhydrophobic coating surface. After a series of characterization and testing, the results showed that the stacking of h-BN lamellae was significantly reduced after h-BN was successfully embedded by MHPS. In addition, the fabricated SLIPS have excellent self-cleaning, mechanical stability, anti-icing and anti-corrosion properties. Therefore, the method of embedding polymer microspheres not only offers a new strategy for h-BN exfoliation, but also the successful prepared SLIPS largely retards the corrosion of Mg alloy while providing new ideas for the development of SLIPS.

关键词： Anti-corrosion Mg alloy Hexagon boron nitride Polypyrrole SLIPS

Ultrafast micro/nano-manufacturing of metastable materials for energy

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National Science Review 2024年第4期11卷 283-298页

作者： Xiaoya Cui Yanchang Liu Yanan Chen School of materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) and Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University ministry of education key laboratory of Protein Sciences School of Life SciencesTsinghua University

The structural engineering of metastable nanomaterials with abundant defects has attracted much attention in energy-related fields. The high-temperature shock(HTS) technique, as a rapidly developing and advanced synthesis strategy, offers significant potential for the rational design and fabrication of high-quality nanocatalysts in an ultrafast, scalable, controllable and eco-friendly way. In this review, we provide an overview of various metastable micro-and nanomaterials synthesized via HTS, including single metallic and bimetallic nanostructures, high entropy alloys, metal compounds(e.g. metal oxides) and carbon nanomaterials. Note that HTS provides a new research dimension for nanostructures, i.e. kinetic modulation. Furthermore, we summarize the application of HTS—as supporting films for transmission electron microscopy grids—in the structural engineering of 2D materials, which is vital for the direct imaging of metastable materials. Finally, we discuss the potential future applications of high-throughput and liquid-phase HTS strategies for non-equilibrium micro/nano-manufacturing beyond energy-related fields.It is believed that this emerging research field will bring new opportunities to the development of nanoscience and nanotechnology in both fundamental and practical aspects.

关键词： high-temperature shock technique defect engineering metastable phase kinetic modulation non-equilibrium micro/nano-manufacturing

Integrated multi-scale approach combining global homogenization and local refinement for multi-field analysis of high-temperature superconducting composite magnets

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 747-762页

作者： Hanxiao GUO Peifeng GAO Xingzhe WANG key laboratory of Mechanics on Western Disaster and environment of ministry of education Key Laboratory of Special Function Materials and Structure Design of Ministry of EducationCollege of Civil Engineering and MechanicsLanzhou UniversityLanzhou 730000China

Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting applications.With respect to epoxy-impregnated REBCO composite magnets that comprise multilayer components,the thermomechanical characteristics of each component differ considerably under extremely low temperatures and strong electromagnetic fields.Traditional numerical models include homogenized orthotropic models,which simplify overall field calculation but miss detailed multi-physics aspects,and full refinement(FR)ones that are thorough but computationally demanding.Herein,we propose an extended multi-scale approach for analyzing the multi-field characteristics of an epoxy-impregnated composite magnet assembled by HTS pancake coils.This approach combines a global homogenization(GH)scheme based on the homogenized electromagnetic T-A model,a method for solving Maxwell's equations for superconducting materials based on the current vector potential T and the magnetic field vector potential A,and a homogenized orthotropic thermoelastic model to assess the electromagnetic and thermoelastic properties at the macroscopic scale.We then identify“dangerous regions”at the macroscopic scale and obtain finer details using a local refinement(LR)scheme to capture the responses of each component material in the HTS composite tapes at the mesoscopic scale.The results of the present GH-LR multi-scale approach agree well with those of the FR scheme and the experimental data in the literature,indicating that the present approach is accurate and efficient.The proposed GH-LR multi-scale approach can serve as a valuable tool for evaluating the risk of failure in large-scale HTS composite magnets.

关键词： epoxy-impregnated high-temperature superconducting(HTS)magnet multi-scale method global homogenization(GH) local refinement(LR) multi-field analysis

Open-Shell Oligomers and polymers: Theory, Characterization Methods, Molecular Design, and Applications

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Chinese Journal of polymer Science 2024年第4期42卷 417-436页

作者： Xue-Qing Wang Cheng Song Ting Lei key laboratory of polymer Chemistry and Physics(ministry of education) School of Materials Science and EngineeringPeking UniversityBeijing100871China

Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.

关键词： Conjugated polymers Open-shell molecules High-spin ground state Donor-acceptor(D-A)polymers Optoelectronic and magnetic properties

Tribological Behaviors of Electroless Nickel-Boron Coating on Titanium Alloy Surface

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 309-320页

作者： Yao Jia Jianping Lai Jiaxin Yu Huimin Qi Yafeng Zhang Hongtu He key laboratory of Testing Technology for Manufacturing Process in ministry of education State Key Laboratory of Environment-Friendly Energy MaterialsSouthwest University of Science and TechnologyMianyang 621010China

Titanium alloys are excellent structural materials in engineering fields,but their poor tribological properties limit their further applications.Electroless plating is an effective method to enhance the tribological performance of alloys,but it is difficult to efficiently apply to titanium alloys,due to titanium alloy’s strong chemical activity.In this work,the electroless Nickel-Boron(Ni-B)coating was successfully deposited on the surface of titanium alloy(Ti-6AL-4V)via a new pre-treatment process.Then,linearly reciprocating sliding wear tests were performed to evaluate the tribological behaviors of titanium alloy and its electroless Ni-B coatings.It was found that the Ni-B coatings can decrease the wear rate of the titanium alloy from 19.89×10^(−3)mm^(3)to 0.41×10^(−3)mm^(3),which attributes to the much higher hardness of Ni-B coatings.After heat treatment,the hardness of Ni-B coating further increases corresponding to coating crystallization and hard phase formation.However,heat treatment does not improve the tribological performance of Ni-B coating,due to the fact that higher brittleness and more severe oxidative wear exacerbate the damage of heat-treated coatings.Furthermore,the Ni-B coatings heat-treated both in air and nitrogen almost present the same tribological performance.The finding of this work on electroless coating would further extend the practical applications of titanium alloys in the engineering fields.

关键词： Electroless coating Titanium alloy Tribology Wear Heat treatment Nanoindentation

Design and synthesis of thiol-terminated imidothioether oligomer as thermally latent hardener and modifier for high-performance epoxy/thiol thermosets

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Science China Chemistry 2024年第2期67卷 632-641页

作者： Xing Liu Jianjun Zhou Shumei Liu Jianqing Zhao School of materials Science and Engineering South China University of TechnologyGuangzhou510640China key Lab Guangdong High Property&Functional polymer materials Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangzhou510640China

Conventional base-catalyzed epoxy/aliphatic thiol systems have a poor storage stability,and are impossible to be one-pot systems.A widely accepted solution is to use the latent catalysts,which are usually insoluble anionic initiators sensitive to impurities and moisture,and have many limitations in practical use.In this work,a soluble thiol-terminated imidothioether oligomer(TPI) was synthesized and used as a latent hardener and modifier to prepare one-pot epoxy/thiol systems without the latent catalysts.The latent behavior and curing mechanism of epoxy systems(EP/TPI series),consisted of bisphenol A diglycidyl ether(DGEBA),pentaerythritol tetrakis(mercaptoacetate)(PETMP) and TPI,were proposed.The thiol exchange reaction between TPI and PETMP preceded the curing reaction of DGEBA,and produced aromatic thiols,which were unreactive at ambient conditions and reacted with DGEBA to form the thermosets at temperatures above 130 ℃.At the loading of 24.4 wt%TPI,the epoxy system(EP/TPI-3) had a shelf life of 13 days and was completely cured within 20 min at 180 ℃.Meanwhile,the catalyst-free curing process of EP/TPI-3 system was insensitive to impurities and moisture.Furthermore,the thermal and mechanical properties of EP/TPI-3 thermoset were simultaneously improved,thereinto,the glass transition temperature,Young's modulus and ultimate tensile strength were increased by 16.7 ℃,12.9%,and 13.6%,respectively,compared with those of the commercial DGEBA/PETMP thermoset.This work shows that TPI has the potential to be a powerful alternative to commercial latent catalysts,and EP/TPI thermosets with high performance have broad application prospects.

关键词： thiol-terminated imidothioether oligomer epoxy systems thiol exchange reaction thermal latency high performance

Highly Transparent Fire-resistant Coatings with Intumescent Three-source Integration

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Chinese Journal of polymer Science 2024年第7期42卷 907-915,I0005页

作者： Xiao-Liang Zeng Xin-Sheng Lan Yan Wang Lin Zhang De-Ming Guo Hai-Bo Zhao State Grid Sichuan Electric Power Research Institute Chengdu610041China The Collaborative Innovation Center for eco-Friendly and Fire-Safety polymeric materials(ministry of education) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu610064China

Wood,a readily available and sustainable natural resource,has found widespread use in construction and furniture.However,its inherent flammability poses a potential fire risk.Although intumescent fire-retardant coatings effectively mitigate this risk,achieving high transparency in such coatings presents a significant challenge.In our approach,we employed a cross-linked network of phytic acid anion and N-[3-(trimethoxysilyl)propyl]-N,N,N-trimethylammonium cation to create a transparent"three-in-one"intumescent coating.The collaborative P/N/Si flame-retardant effect markedly improved the intumescent char-forming capability,preventing the wood from rapid decomposition.This resulted in a substantial reduction in heat release(13.9%decrease in THR)and an increased limiting oxygen index(LOI)value of 35.5%.Crucially,the high transparency of the coating ensured minimal impact on the wood's appearance,allowing the natural wood grains to remain clearly visible.This innovative approach provides a straightforward method for developing transparent intumescent flame-retardant coatings suitable for wooden substrates.The potential applications extend to preserving ancient buildings and heritage conservation efforts.

关键词： Fire-resistant coating Flame retardancy Wood Transparency

Fabrication of Molecularly Imprinted Electrospun Nanofibers with Mono-amidoxime Functional Ligand for Efficient Decontamination of Toxic Organophosphates

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Chinese Journal of polymer Science 2024年第4期42卷 446-456页

作者： Lan Wang Peng Jiang Ya-Lin Niu Jun-Peng Cao Tian-Ying Guo key laboratory of Functional polymer materials Ministry of EducationInstitute of Polymer ChemistryCollege of Chemistry and Frontier Science Center for the Creation of New Organic SubstancesNankai UniversityTianjin300071China

There is an urgent imperative to discover practical and efficacious artificial catalysts for the expeditious decontamination of toxic organophosphates. Herein, we propose a novel molecularly imprinted approach utilizing electrospun fiber scaffolds. Specifically, an amidoxime-based functional polymer (PMAOX) has been synthesized, which contains amidoxime groups that can act as nucleophiles and ligands for the formation of catalytic active sites. This polymer was blended with polyacrylonitrile (PAN), a well-processable material, to prepare a nanofiber mat using electrospinning techniques. Then, the amidoxime side groups on fiber surface were further cross-linked after the molecular coordination of templates to complete the molecularly imprinting process. This approach can not only enhance the content of functional molecularly imprinted polymers without affecting structural stability, but also combines surface MI technology to fully expose and leverage the advantages of active sites. The as prepared molecularly imprinted electrospun nanofibers MIF-Zn-PMAOX/PAN-6/4 catalyzes the degradation of paraoxon with a half-life of 32 min, and MIF-Ag-PMAOX/PAN catalyzes the degradation of parathion with a half-life of 18 min. The maximum catalytic rate evidence rate enhancements nearly 3700-fold of the self-hydrolysis. Thus, the mono-amidoxime based molecularly imprinted fibers demonstrate the versatility and superiority as self-detoxifying for organophosphates.

关键词： Organophosphateshydrolysis Electrospinning Molecular imprinting

Inhibiting shuttle effect of lithium polysulfides by double metal selenides for high-performance lithium-sulfur batteries

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Rare Metals 2024年第6期43卷 2546-2559页

作者： Lei Li Xue-Jing Yang Yi-Yang Li Bo Jin Hui Liu Meng-Yang Cui Dong-Bo Guan Xing-You Lang Qing Jiang key laboratory of Automobile materials Ministry of Educationand College of Materials Science and EngineeringJilin University

Lithium-sulfur batteries（LSBs） have attracted the attention of more and more researchers due to the advantages of high energy density,environmental friendliness,and low production cost.However,the low electronic conductivity of active material and shuttling effect of lithium polysulfides（LiPSs） limit the commercial development of LSBs.To solve these problems,we design a core-shell composite with nitrogen-doped carbon（NC） and two types of selenides（FeSe2-NC@ZnSe-NC）.The FeSe2-NC@ZnSe-NC has a strong adsorption capacity,and can effectively adsorb LiPSs.At the same time,it also effectively alleviates the shuttling effect of LiPSs,and improves the utilization of the active substance during the charge/discharge reaction processes.The mechanism involved in FeSe2-NC@ZnSe-NC is demonstrated by both experiments and density-functional theory（DFT） calculations.The electrochemical test results indicate that LSB with S/FeSe2-NC@ZnSe-NC delivers an initial discharge capacity of 1260 mAh·g-1at 0.2C.And after 500 cycles at 1C,the capacity decay rate per cycle is 0.031%,and the capacity retention rate is 85%.The FeSe2-NC@ZnSe-NC core-shell structure verifies a rational strategy to construct an electrode material for high-performance LSBs.

关键词： Lithium–sulfur batteries Shuttling effect Metal selenide Nitrogen-doped carbon Lithium polysulfides