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Thermoviscoelastic Modeling Approach for Predicting the Recovery Behaviors of Thermally Activated Amorphous Shape Memory Polymers

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第5期36卷 798-807页

作者： GU Jianping FANG Changqing SUN Huiyu ZHANG Xiaopeng Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of TechnologyNanjing 211167P.R.China Shanghai Space Propulsion Technology Research Institute Shanghai 201109P.R.China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

A thermoviscoelastic modeling approach is developed to predict the recovery behaviors of the thermally activated amorphous shape memory polymers(SMPs)based on the generalized finite deformation viscoelasticity *** this paper,a series of moduli and relaxation times of the generalized Maxwell model is estimated from the stress relaxation master curve by using the nonlinear regression(NLREG)*** that the amorphous SMPs are approximately incompressible isotropic elastomers in the rubbery state,the hyperelastic response of the materials is well modeled with a hyperelastic model in Ogden *** addition,the Williams-Landel-Ferry(WLF)equation is used to describe the horizontal shift factor obtained with time-temperature superposition principle(TTSP).The finite element simulations show good agreement with the experimental thermomechanical ***,the possibility of developing a temperature-responsive intravascular stent with the SMP studied here is investigated in terms of its thermomechanical ***,it can be concluded that the model has good prediction capabilities for the recovery behaviors of amorphous SMPs.

关键词： shape memory polymers(SMPs) thermoviscoelastic modeling approach finite deformation recovery behavior

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Construction and fabrication of Zn(In 0.1 Ga 0.9 ) 2 O 4 /NH 2 -MIL-125(Ti-Zr) composite materials with S-scheme heterojunction for highly efficient photocatalytic degradation of organic pollutants

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materials Science in Semiconductor Processing 2025年 198卷

作者： Zhixiong Huang Lingxiu Shu Changchun Chen Yupeng Shi Chenxi Cui Zishen Guan Yifeng Wang Lin Pan College of Materials Science and Engineering Nanjing Tech University No. 30 Puzhu Road (S) Nanjing 211816 PR China State Key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co. Ltd. Bengbu Anhui 233000 PR China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing Tech University No. 5 New Model Road 210009 Nanjing PR China

The effective degradation of organic dyes and tetracycline in wastewater is crucial for environmental protection. Currently, photocatalytic degradation using S-scheme heterojunction catalysts represents an efficient solution. In this study, we employed doping engineering by partially substituting Ga 3+ with In 3+ in ZnGa 2 O 4 and Ti 4+ with Zr 4+ in NH 2 -MIL-125(Ti) to modulate their band edge positions and bandgaps. This approach successfully constructed an S-scheme Zn(In 0.1 Ga 0.9 ) 2 O 4 /NH 2 -MIL-125(Ti-Zr) composite photocatalyst with enhanced built-in electric field. The composite photocatalysts were synthesized via a hydrothermal together with a solvothermal method. Field emission SEM images of the samples showed that the disc-shaped NH 2 -MIL-125(Ti-Zr) was effectively attached to the irregular small particles of Zn(In 0.1 Ga 0.9 ) 2 O 4 . The existence of an S-scheme heterojunction at the interface of Zn(In 0.1 Ga 0.9 ) 2 O 4 and NH 2 -MIL-125 (Ti-Zr) was confirmed through various characterization techniques, including photoelectrochemical tests, XPS analysis, and free radical trapping experiments. As demonstrated by photocatalytic experiments, the NZ-20 % composite has the highest photocatalytic activity and good stability. The degradation efficiencies for Rh. B and tetracycline over the NZ-20 % composite sample under solar light irradiation for 90 min are 96.3 % and 88.5 %, respectively. Additionally, the response surface methodology (RSM) was employed to analyze the key factors affecting the photocatalytic degradation of organic pollutants, namely pH value, temperature, and contaminant level. All in all, this work presents a potential strategy to fabricate superior composite photocatalysts with S-scheme heterojunctions for combating environmental pollution challenges.

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Construction of surface pit-structured g-C 3 N 4 by induced SiO 2 hard template for boosted piezoelectric-assisted photocatalytic H 2 O 2 production

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Journal of Colloid and Interface Science 2025年第PT 1期699卷 138118页

作者： Zixuan Guo Kaiqu Sun Suchang Zou Bo Xiong Lijing Wang Weilong Shi Yan Sun Feng Guo School of Energy and Power Jiangsu University of Science and Technology Zhenjiang Jiangsu 212114 China School of Material Science and Engineering Jiangsu University of Science and Technology Zhenjiang Jiangsu 212114 China School of Chemistry and Materials Science Hubei Key Laboratory of Quality Control of Characteristic Fruits and Vegetables Hubei Engineering University Xiaogan 432000 China Henan Engineering Center of New Energy Battery Materials College of Chemistry and Chemical Engineering Shangqiu Normal University Shangqiu 476000 China Key Laboratory of Advanced Electrode Materials for Novel Solar Cells for Petroleum and Chemical Industry of China School of Chemistry and Life Sciences Suzhou University of Science and Technology Suzhou City Jiangsu Province 215009 China

Solar-driven synthesis of hydrogen peroxide (H 2 O 2 ) represents a promising pathway for sustainable energy production, characterized by environmental friendliness and industrial feasibility. The coupling of multi-field co-assisted systems, integrating piezoelectric field modulation, represents a pioneering modification strategy that significantly enhances the photocatalytic H 2 O 2 production efficiency through synergistic interfacial charge separation and optimized redox kinetics. Herein, the surface pit-structured g-C 3 N 4 (SP-CN) was successfully synthesized via a straightforward hard-template-assisted thermal polymerization method for boosted piezoelectric-assisted photocatalytic H 2 O 2 production under full-spectrum irradiation. Systematic investigations demonstrate that these surface pits of SP-CN endow the material with dual functional enhancements, including broadened light absorption and amplified dipole moment, promotes charge carrier separation/migration under piezoelectric polarization while creating abundant exposed active sites for oxygen adsorption. The testing results indicated that under piezoelectric-assisted photocatalysis, the H 2 O 2 generation rate of SP-CN reached 189.8 μM·h −1 (227.76 μmol·g −1 ·h −1 ), which is 14.4 times that of g-C 3 N 4 under sole photocatalysis, and the saturation phenomenon observed in the later stages of performance testing highlighted its exceptional capability. In addition, cyclic testing confirms that SP-CN can still maintain its activity after multiple reactions. This unique structural configuration establishes a synergistic piezoelectric-photocatalytic system that effectively addresses the intrinsic limitations of conventional g-C 3 N 4 through simultaneous improvements in photon utilization, charge dynamics, and surface reactivity.

关键词： H(2)O(2) production Photocatalytic Piezoelectric-assisted Pit-structured g-C(3)N(4) SiO(2) hard template

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Chitosan/ZIF-8 interface-modified ammonium polyphosphate as core-shell additive for synergistically enhancing flame retardancy and degradation performance of polylactic acid

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International journal of biological macromolecules 2025年 145114页

作者： Xinyu Cui Yichao Lin Shuchen Wang Ruiqi Li Jian Liu Jun Sun Ye-Tang Pan Sheng Zhang State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Beijing 100029 China. Guangdong Advanced Carbon Materials Co. Ltd Zhuhai Guangdong 519000 China Key Laboratory of Gas and Fire Control for Coal Mines State Key Laboratory of Coal Mine Disaster Prevention and Control China University of Mining and Technology Xuzhou Jiangsu 221116 China. Electronic address: linyichao2007@***. Guangdong Advanced Carbon Materials Co. Ltd Zhuhai Guangdong 519000 China. State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Beijing 100029 China. Electronic address: sunj@***. National Engineering Research Center of Flame Retardant Materials School of Materials Science & Engineering Beijing Institute of Technology Beijing 100081 China. Electronic address: pyt@***.

Polylactic acid (PLA) is a promising renewable polymer material known for its excellent biodegradability and good mechanical properties. However, its easy flammability and slow natural degradation limit its further applications. In this work, we designed a multi-layer core-shell flame retardant (ZIF-8@CH@APP) with interfacial characteristics through organic-inorganic hybrid technology. The interfacial functionalization of inorganic flame retardant ammonium polyphosphate (APP) was carried out with bio-based chitosan (CH), and the three-dimensional network was constructed by in-situ growth of metal-organic framework (ZIF-8). With 7 wt% addition of ZIF-8@CH@APP, the PLA composite exhibited excellent flame retarded properties. It showed V-0 vertical burning (UL-94) grade, and reduced total smoke produce (TSP) (0.2 m). Additionally, the PLA/7 % ZIF-8@CH@APP composite exhibited higher degradation rate at mild condition. Additionally, the final degradation product of ZIF-8@CH@APP was confirmed to be DL-lactic acid. The design not only improves the interface compatibility between inorganic phase and polymer matrix, but also realizes the double breakthrough of flame retardant and catalytic degradation function through physical-chemical synergism, providing an innovative solution for the recycle of PLA material.

关键词： Chitosan Flame retardancy Polylactic acid

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Effectively Regulating Electrooxidation Pathway of Formic Acid Over Bimetallic PtCo Alloys Via the Integration of Theory and Experiment

SSRN

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SSRN 2024年

作者： Zheng, Zhikeng Liu, Bin Xu, Shaojun Wang, Yuchen Zhang, Man Chen, Yuwen Li, Ziang Wan, Yangyang Catlow, C.A. Richard Yan, Kai Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology School of Environmental Science and Engineering Sun Yat-sen University Guangzhou510275 China Department of Chemical Engineering University of Manchester ManchesterM13 9PL United Kingdom School of Chemistry Cardiff University Main Building Park Place CardiffCF10 3AT United Kingdom Rutherford Appleton Laboratory Research Complex at Harwell R92 Harwell OxfordshireOX11 0FA United Kingdom Institute for Advanced Materials School of Materials Science and Engineering Jiangsu University Zhenjiang212013 China Department of Chemistry University College London 20 Gordon Street LondonWC1H 0AJ United Kingdom

Challenges in directly regulating reaction pathways in small molecules electrooxidation have hindered widespread applications. Hence, we report directly tuning the pathway of formic acid oxidation (FAO) through the integration of theoretical and experimental approaches. DFT calculations indicate that the Pt1Co1 alloy with 50% Co incorporation is an ideal candidate for HCOO* formation with a significantly lower Gibbs free energy (−0.296 eV) compared to that of COOH* (0.028 eV), which reverses the trend on Pt. Guided by theoretical predictions, we fabricate bimetallic PtCo alloys using an eco-friendly microwave method. The Pt1Co1 alloy exhibits a 121-fold increased activity (1.18 A mgPt−1) compared to Pt. In situ infrared spectra confirm that PtCo alloys catalyze FAO through the direct pathway, suggesting a crucial role of Co in enhancing Pt's resistance to CO poisoning, perfectly aligning with the predicted changes. This work provides an essential reference for the rational development of high-efficiency Pt-based alloy electrocatalysts. © 2024, The Authors. All rights reserved.

关键词： Electrocatalysis

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Localization of chiral edge states by the non-Hermitian skin effect

arXiv

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arXiv 2023年

作者： Liu, Gui-Geng Mandal, Subhaskar Zhou, Peiheng Xi, Xiang Banerjee, Rimi Hu, Yuan-Hang Wei, Minggui Wang, Maoren Wang, Qiang Gao, Zhen Chen, Hongsheng Yang, Yihao Chong, Yidong Zhang, Baile Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore637371 Singapore National Engineering Research Center of Electromagnetic Radiation Control Materials State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of China Chengdu610054 China Department of Electrical and Electronic Engineering Southern University of Science and Technology Shenzhen518055 China School of Physics Collaborative Innovation Center of Advanced Microstructures Nanjing University Jiangsu Nanjing210093 China Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentation ZJU-Hangzhou Global Science and Technology Innovation Center College of Information Science and Electronic Engineering Key Lab. of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang ZJU-UIUC Institute Zhejiang University Hangzhou310027 China Centre for Disruptive Photonic Technologies The Photonics Institute Nanyang Technological University 50 Nanyang Avenue Singapore639798 Singapore

Quantum Hall systems host chiral edge states extending along the one-dimensional boundary of any two-dimensional sample. In solid state materials, the edge states serve as perfectly robust transport channels that produce a quantised Hall conductance;due to their chirality, and the topological protection by the Chern number of the bulk bandstructure, they cannot be spatially localized by defects or disorder. Here, we show experimentally that the chiral edge states of a lossy quantum Hall system can be localized. In a gyromagnetic photonic crystal exhibiting the quantum Hall topological phase, an appropriately structured loss configuration imparts the edge states’ complex energy spectrum with a feature known as point-gap winding. This intrinsically non-Hermitian topological invariant is distinct from the Chern number invariant of the bulk (which remains intact) and induces mode localization via the "non-Hermitian skin effect". The interplay of the two topological phenomena – the Chern number and point-gap winding – gives rise to a non-Hermitian generalisation of the paradigmatic Chern-type bulk-boundary correspondence principle. Compared to previous realisations of the non-Hermitian skin effect, the skin modes in this system have superior robustness against local defects and disorders. Copyright © 2023, The Authors. All rights reserved.

关键词： Topology

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Strong Magneto-Chiroptical Effects through Introducing Chiral Transition-Metal Complex Cations to Lead Halide

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Angewandte Chemie 2024年第3期137卷

作者： Haolin Lu Fenglian Qi Hebin Wang Tengfei He Bing Sun Prof. Xiaoqing Gao Andrew H. Comstock Sehrish Gull Yunxin Zhang Tianjiao Qiao Tianyin Shao Prof. You-Xuan Zheng Prof. Dali Sun Prof. Yongsheng Chen Prof. Hao-Li Zhang Prof. Zhiyong Tang Prof. Guankui Long Tianjin Key Lab for Rare Earth Materials and Applications Renewable Energy Conversion and Storage Center (RECAST) Smart Sensing Interdisciplinary Science Center School of Materials Science and Engineering National Institute for Advanced Materials Nankai University Tianjin 300350 China Chinese Academy of Science (CAS) Key Laboratory of Nanosystem and Hierarchy Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer Chemistry Renewable Energy Conversion and Storage Center (RECAST) College of Chemistry Nankai University Tianjin 300350 China State Key Laboratory of Applied Organic Chemistry (SKLAOC) Key Laboratory of Special Function Materials and Structure Design (MOE) College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 China Wenzhou Institute University of Chinese Academy of Sciences Wenzhou 325000 China Department of Physics North Carolina State University Raleigh NC 27695–8202 USA State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced Microstructures Jiangsu Key Laboratory of Advanced Organic Materials School of Chemistry and Chemical Engineering Nanjing University Nanjing 210023 China

The interplay between chirality with magnetism can break both the space and time inversion symmetry and have wide applications in information storage, photodetectors, multiferroics and spintronics. Herein, we report the chiral transition-metal complex cation-based lead halide, R -CDPB and S -CDPB. In contrast with the traditional chiral metal halides with organic cations, a novel strategy for chirality transfer from the transition-metal complex cation to the lead halide framework is developed. The chiral complex cations directly participate the band structure and introduce the d - d transitions and tunable magneto-chiroptical effects in both the ultraviolet and full visible range into R -CDPB and S -CDPB. Most importantly, the coupling between magnetic moment of the complex cation and chiroptical properties is confirmed by the magneto-chiral dichroism. For the band-edge transition, the unprecedented modulation of +514 % for S -CDPB and −474 % for R -CDPB was achieved at −1.3 Tesla. Our findings demonstrate a novel strategy to combine chirality with magnetic moment, and provide a versatile material platform towards magneto-chiroptical and chiro-spintronic applications.

关键词： chiral lead halide complex ion chiroptical effect magneto-chiral dichroism A-site engineering

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Rapid identification of two-dimensional materials via machine learning assisted optic microscopy

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Journal of Materiomics 2019年第3期5卷 413-421页

作者： Yuhao Li Yangyang Kong Jinlin Peng Chuanbin Yu Zhi Li Penghui Li Yunya Liu Cun-Fa Gao Rong Wu Shenzhen Key Laboratory of Nanobiomechanics Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055GuangdongChina School of Physics Science and Technology Xinjiang UniversityUrumqi830046XinjiangChina State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics&AstronauticsNanjing210016JiangsuChina Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education Xiangtan UniversityXiangtan411105HunanChina Institute of Biomedicine and Biotechnology Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055GuangdongChina

A combination of Fresnel law and machine learning method is proposed to identify the layer counts of 2D *** indexes,which are optical contrast,red-green-blue,total color difference,are presented to illustrate and simulate the visibility of 2D materials on Si/SiO_(2) substrate,and the machine learning algorithms,which are k-mean clustering and k-nearest neighbors,are employed to obtain thickness database of 2D material and test the optical images of 2D materials via red-green-blue *** results show that this method can provide fast,accurate and large-area property of 2D *** the combination of artificial intelligence and nanoscience,this machine learning assisted method eases the workload and promotes fundamental research of 2D materials.

关键词： Two-dimensional materials Optical contrast Total color difference Red-green-blue K-means clustering K-nearest neighbors(k-NN)

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Polyamorphism mediated by nanoscale incipient concentration wave uncovering hidden amorphous intermediate state with ultrahigh modulus in nanostructured metallic glass

材料展望（英文）

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材料展望（英文） 2023年第2期 123-133页

作者： Qiang Luo Weiran Cui Huaping Zhang Liangliang Li Liliang Shao Mingjuan Cai Zhengguo Zhang Lin Xue Jun Shen Yu Gong Xiaodong Li Maozi Li Baolong Shen School of Materials Science and Engineering Jiangsu Key Laboratory for Advanced Metallic MaterialsSoutheast UniversityNanjing 211189People's Republic of China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049People's Republic of China University of Chinese Academy of Sciences Beijing 100049People's Republic of China Institute of Physics Chinese Academy of SciencesBeijing 100190People's Republic of China Department of Physics Renmin University of ChinaBeijing 100872People's Republic of China Inner Mongolia University of Science & Technology Baotou 014010People's Republic of China College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060People's Republic of China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049People's Republic of China Department of Physics Renmin University of ChinaBeijing 100872People's Republic of China

Comprehending the pressure-/temperature-induced structural transition in glasses,as one of the most fascinating issues in material science,is far from being well ***,we report novel polyamorphic transitions in a Cu-based metallic glass(MG)with apparent nanoscale structural heterogeneity relating to proper Y *** low-density MG compresses continuously with increasing pressure,and then a compression plateau appears after～8.1 GPa,evolving into an intermediate state with an ultrahigh bulk modulus of～467 *** then transforms to a high-density MG with significantly decreased structural heterogeneity above～14.1 ***-dimensional atom probe tomography reveals concentration waves of Cu/Zr elements with an average wavelength of～5-6 nm,which promote the formation of interconnected ringlike networks composed of Cu-rich and Zr-rich dual-glass domains at nanometer *** experimental and simulation results indicate that steplike polyamorphism may stem from synergic effects of the abnormal compression of the Zr-Zr bond length at the atomic scale and the interplay between the applied pressure and incipient concentration waves(Cu and Zr)at several nanometer *** present work provides new insights into polyamorphism in glasses and contributes to the development of high-performance amorphous materials by high-pressure nanostructure engineering.

关键词： metallic glasses heterogeneity concentration wave polyamorphism

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Bio-templated formation of defect-abundant VS_2 as a bifunctional material toward high-performance hydrogen evolution reactions and lithium-sulfur batteries

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Journal of Energy Chemistry 2020年 42卷 34-42页

作者： Guo Tianqi Song Yingze Sun Zhongti Wu Yuhan Xia Yu Li Yayun Sun Jianhui Jiang Kai Dou Shixue Sun Jingyu School of Environment Henan Normal University Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control-Ministry of Education Henan Xinxiang 453007 College of Energy Soochow Institute for Energy and Materials Innovations Soochow University Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province Jiangsu Suzhou 215006 College of Materials Science and Engineering Shenzhen University Shenzhen Key Laboratory of Special Functional Materials Shenzhen Engineering Laboratory for Advance Technology of Ceramics Guangdong Shenzhen 518060 Institute for Superconducting and Electronic Materials University of Wollongong Australia Wollongong NSW 2522

Transition metal chalcogenides have nowadays garnered burgeoning interest owing to their fascinating electronic and catalytic properties, thus possessing great implications for energy conversion and storage applications. In this regard, their controllable synthesis in a large scale at low cost has readily become a focus of research. Herein we report diatomite-template generic and scalable production of VS_2 and other transition metal sulfides targeting emerging energy conversion and storage applications. The conformal growth of VS_2 over diatomite template would endow them with defect-abundant features. Throughout detailed experimental investigation in combination with theoretical simulation, we reveal that the enriched active sites/sulfur vacancies of thus-derived VS_2 architectures would pose positive impacts on the catalytic performance such in electrocatalytic hydrogen evolution reactions. We further show that the favorable electrical conductivity and highly exposed sites of VS_2 hold promise for serving as sulfur host in the realm of Li-S batteries. Our work offers new insights into the templated and customized synthesis of defect-rich sulfides in a scalable fashion to benefit multifunctional energy applications.

关键词： Bio-templated Vanadium disulfide Defect-abundant Hydrogen evolution reaction Lithium-sulfur batteries

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