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Recent Progresses in Synthesis of Cyclic Polymers in Large-scale and Some Functionalized Composites
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作者 QU Kairu GUO Lyuzhou +3 位作者 WANG Wenbin YAN Xuzhou CAO Xuezheng YANG Zhenzhong 《高等学校化学学报》 北大核心 2026年第1期42-57,共16页
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam... Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering. 展开更多
关键词 Cyclic polymer Large-scale synthesis Single-chain nanoparticle Performance Composite
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Iron-nitrogen-doped porous carbon absorbers constructed from hypercrosslinked ferrocene polymers for efficient electromagnetic wave absorption 被引量:1
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作者 Yi Hu Yijia Zhou +4 位作者 Lijia Liu Qiang Wang Chunhong Zhang Hao Wei Yudan Wang 《International Journal of Minerals,Metallurgy and Materials》 2025年第3期578-590,共13页
Herein,an external crosslinker facilitated the hypercrosslinking of ferrocene and a nitrogen heterocyclic compound(either melamine or imidazole)through a direct Friedel-Crafts reaction,which led to the formation of ni... Herein,an external crosslinker facilitated the hypercrosslinking of ferrocene and a nitrogen heterocyclic compound(either melamine or imidazole)through a direct Friedel-Crafts reaction,which led to the formation of nitrogen-containing hypercrosslinked fer-rocene polymer precursors(HCP-FCs).Subsequent carbonization of these precursors results in the production of iron-nitrogen-doped por-ous carbon absorbers(Fe-NPCs).The Fe-NPCs demonstrate a porous structure comprising aggregated nanotubes and nanospheres.The porosity of this structure can be modulated by adjusting the iron and nitrogen contents to optimize impedance matching.The uniform dis-tribution of Fe-N_(x)C,N dipoles,andα-Fe within the carbon matrix can be ensured by using hypercrosslinked ferrocenes in constructing porous carbon,providing the absorber with numerous polarization sites and a conductive network.The electromagnetic wave absorption performance of the specially designed Fe-NPC-M_(2)absorbers is satisfactory,revealing a minimum reflection loss of-55.3 dB at 2.5 mm and an effective absorption bandwidth of 6.00 GHz at 2.0 mm.By utilizing hypercrosslinked polymers(HCPs)as precursors,a novel method for developing highly efficient carbon-based absorbing agents is introduced in this research. 展开更多
关键词 hypercrosslinked polymers porous carbon iron-nitrogen doping annealing
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Sulfur-Doped Carbonized Polymer Dots:A Biocompatible Photocatalyst for Rapid Aqueous PET-RAFT Polymerization 被引量:1
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作者 Yue Yu Songyuan Tao +3 位作者 Qingsen Zeng Zhihui Ma Kai Zhang Bai Yang 《Carbon Energy》 2025年第3期186-195,共10页
To achieve the target of carbon neutrality,it is crucial to develop an efficient and green synthesis methodology with good atomic economy to achieve sufficient utilization of energy and sustainable development.Photoin... To achieve the target of carbon neutrality,it is crucial to develop an efficient and green synthesis methodology with good atomic economy to achieve sufficient utilization of energy and sustainable development.Photoinduced electron transfer reversible addition-fragmentation chain-transfer(PET-RAFT)polymerization is a precise methodology for constructing polymers with well-defined structures.However,conventional semiconductor-mediated PET-RAFT polymerization still has considerable limitations in terms of efficiency as well as the polymerization environment.Herein,sulfur-doped carbonized polymer dots(CPDs)were hydrothermally synthesized for catalysis of aqueous PET-RAFT polymerization at unprecedented efficiency with a highest propagation rate of 5.05 h-1.The resulting polymers have well-controlled molecular weight and narrow molecular weight dispersion(Ð<1.10).Based on the optoelectronic characterizations,we obtained insights into the photoinduced electron transfer process and proposed the mechanism for CPD-mediated PET-RAFT polymerization.In addition,as-synthesized CPDs for PET-RAFT polymerization were also demonstrated to be suitable for a wide range of light sources(blue/green/solar irradiation),numerous monomers,low catalyst loading(low as 0.01 mg mL^(-1)),and multiple polar solvent environments,all of which allowed to achieve efficiencies much higher than those of existing semiconductor-mediated methods.Finally,the CPDs were confirmed to be non-cytotoxic and catalyzed PET-RAFT polymerization successfully in cell culture media,indicating broad prospects in biomedical fields. 展开更多
关键词 aqueous PET-RAFT polymerization carbonized polymer dots photocatalysis ultrahigh efficiency
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An Emerging Liquid‑Crystalline Conducting Polymer Thermoelectrics:Opportunities and Challenges
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作者 Zhenqiang Ye Mingdong Zhang +3 位作者 Junyang Deng Lirong Liang Chunyu Du Guangming Chen 《Nano-Micro Letters》 2026年第3期240-273,共34页
Thermoelectric(TE)materials,being capable of converting waste heat into electricity,are pivotal for sustainable energy solutions.Among emerging TE materials,organic TE materials,particularly conjugated polymers,are ga... Thermoelectric(TE)materials,being capable of converting waste heat into electricity,are pivotal for sustainable energy solutions.Among emerging TE materials,organic TE materials,particularly conjugated polymers,are gaining prominence due to their unique combination of mechanical flexibility,environmental compatibility,and solution-processable fabrication.A notable candidate in this field is poly(2,5-bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophene)(PBTTT),a liquid-crystalline conjugated polymer,with high charge carrier mobility and adaptability to melt-processing techniques.Recent advancements have propelled PBTTT’s figure of merit from below 0.1 to a remarkable 1.28 at 368 K,showcasing its potential for practical applications.This review systematically examines strategies to enhance PBTTT’s TE performance through doping(solution,vapor,and anion exchange doping),composite engineering,and aggregation state controlling.Recent key breakthroughs include ion exchange doping for stable charge modulation,multi-heterojunction architectures reducing thermal conductivity,and proton-coupled electron transfer doping for precise Fermi-level tuning.Despite great progress,challenges still persist in enhancing TE conversion efficiency,balancing or decoupling electrical conductivity,Seebeck coefficient and thermal conductivity,and leveraging melt-processing scalability of PBTTT.By bridging fundamental insights with applied research,this work provides a roadmap for advancing PBTTT-based TE materials toward efficient energy harvesting and wearable electronics. 展开更多
关键词 Thermoelectric materials polymer PBTTT LIQUID-CRYSTALLINE
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Merging polymers of intrinsic microporosity and porous carbon-based zinc oxide composites in novel mixed matrix membranes for efficient gas separation
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作者 Muning Chen Jiemei Zhou +7 位作者 Jing Ma Weigang Zheng Guanying Dong Xin Li Zhihong Tian Yatao Zhang Jing Wang Yong Wang 《Green Energy & Environment》 SCIE EI CAS 2025年第1期203-213,共11页
Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of polymers.However,achieving a sim... Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of polymers.However,achieving a simultaneous enhancement of permeability and selectivity remains a formidable challenge,due to the difficulty of achieving an optimal match between polymers and fillers.In this study,we incorporate a porous carbon-based zinc oxide composite(C@ZnO)into high-permeability polymers of intrinsic microporosity(PIMs)to fabricate MMMs.The dipole–dipole interaction between C@ZnO and PIMs ensures their exceptional compatibility,mitigating the formation of non-selective voids in the resulting MMMs.Concurrently,C@ZnO with abundant interconnected pores can provide additional low-resistance pathways for gas transport in MMMs.As a result,the CO_(2) permeability of the optimized C@ZnO/PIM-1 MMMs is elevated to 13,215 barrer,while the CO_(2)/N_(2) and CO_(2)/CH_(4) selectivity reached 21.5 and 14.4,respectively,substantially surpassing the 2008 Robeson upper bound.Additionally,molecular simulation results further corroborate that the augmented membrane gas selectivity is attributed to the superior CO_(2) affinity of C@ZnO.In summary,we believe that this work not only expands the application of MMMs for gas separation but also heralds a paradigm shift in the application of porous carbon materials. 展开更多
关键词 Mixed matrix membranes polymers of intrinsic microporosity CO_(2)separation Porous carbon materials
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P,N co-doped hollow carbon nanospheres prepared by micellar copolymerization for increased hydrogen evolution in alkaline water 被引量:1
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作者 HAN Yi-meng XIONG Hao +2 位作者 YANG Jia-ying WANG Jian-gan XU Fei 《新型炭材料(中英文)》 北大核心 2025年第1期211-221,共11页
The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alka... The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds. 展开更多
关键词 Alkaline hydrogen evolution ELECTROCATALYSTS Hollow carbon nanospheres Dual atoms doping Combined effect
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Deterioration and Pore Structure Evolution of GO Modified Polymer Cement Mortar under Salt-freeze-thaw Coupling Effects
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作者 ZHAO Xinyuan WEI Zhiqiang +3 位作者 QIAO Hongxia LI Shaofei CAO Hui XI Lingling 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期234-246,共13页
To investigate the pore structure of graphene oxide modified polymer cement mortar(GOPM)under salt-freeze-thaw(SFT)coupling effects and its impact on deterioration,this study modifies polymer cement mortar(EMCM)with g... To investigate the pore structure of graphene oxide modified polymer cement mortar(GOPM)under salt-freeze-thaw(SFT)coupling effects and its impact on deterioration,this study modifies polymer cement mortar(EMCM)with graphene oxide(GO).The micro-pore structure of GOPM is characterized using LF-NMR and SEM.Fractal theory is applied to calculate the fractal dimension of pore volume,and the deterioration patterns are analyzed based on the evolution characteristics of capillary pores.The experimental results indicate that,after 25 salt-freeze-thaw cycles(SFTc),SO2-4 ions penetrate the matrix,generating corrosion products that fill existing pores and enhance the compactness of the specimen.As the number of cycles increases,the ongoing formation and expansion of corrosion products within the matrix,combined with persistent freezing forces,and result in the degradation of the pore structure.Therefore,the mass loss rate(MLR)of the specimens shows a trend of first decreasing and then increasing,while the relative dynamic elastic modulus(RDEM)initially increases and then decreases.Compared to the PC group specimens,the G3PM group specimens show a 28.71% reduction in MLR and a 31.42% increase in RDEM after 150 SFTc.The fractal dimensions of the transition pores,capillary pores,and macropores in the G3PM specimens first increase and then decrease as the number of SFTc increases.Among them,the capillary pores show the highest correlation with MLR and RDEM,with correlation coefficients of 0.97438 and 0.98555,respectively. 展开更多
关键词 graphene oxide polymer cement mortar pore structure fractal dimension
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Advances in polymer-based hydrogel systems for adipose-derived mesenchymal stem cells toward bone regeneration
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作者 Nivetha Suresh Sundaravadhanan Lekhavadhani Nagarajan Selvamurugan 《World Journal of Orthopedics》 2026年第1期13-28,共16页
Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant i... Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant interest in bone tissue engineering(BTE)because of their abundant availability,minimally invasive harvesting procedures,and robust differentiation potential into osteogenic lineages.Unlike bone marrow-derived mesenchymal stem cells,AD-MSCs can be easily obtained in large quantities,making them appealing alternatives for therapeutic applications.This review explores hydrogels containing polymers,such as chitosan,collagen,gelatin,and hyaluronic acid,and their composites,tailored for BTE,and emphasizes the importance of these hydrogels as scaffolds for the delivery of AD-MSCs.Various hydrogel fabrication techniques and biocompatibility assessments are discussed,along with innovative modifications to enhance osteogenesis.This review also briefly outlines AD-MSC isolation methods and advanced embedding techniques for precise cell placement,such as direct encapsulation and three-dimensional bioprinting.We discuss the mechanisms of bone regeneration in the AD-MSC-laden hydrogels,including osteoinduction,vascularization,and extracellular matrix remodeling.We also review the preclinical and clinical applications of AD-MSC-hydrogel systems,emphasizing their success and limitations.In this review,we provide a comprehensive overview of AD-MSC-based hydrogel systems to guide the development of effective therapies for bone regeneration. 展开更多
关键词 Mesenchymal stem cells Adipose-derived mesenchymal stem cells Bone tissue engineering HYDROGELS Bone regeneration polymerS
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Lithium-Ion Dynamic Interface Engineering of Nano-Charged Composite Polymer Electrolytes for Solid-State Lithium-Metal Batteries
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作者 Shanshan Lv Jingwen Wang +7 位作者 Yuanming Zhai Yu Chen Jiarui Yang Zhiwei Zhu Rui Peng Xuewei Fu Wei Yang Yu Wang 《Nano-Micro Letters》 2026年第2期288-305,共18页
Composite polymer electrolytes(CPEs)offer a promising solution for all-solid-state lithium-metal batteries(ASSLMBs).However,conventional nanofillers with Lewis-acid-base surfaces make limited contribution to improving... Composite polymer electrolytes(CPEs)offer a promising solution for all-solid-state lithium-metal batteries(ASSLMBs).However,conventional nanofillers with Lewis-acid-base surfaces make limited contribution to improving the overall performance of CPEs due to their difficulty in achieving robust electrochemical and mechanical interfaces simultaneously.Here,by regulating the surface charge characteristics of halloysite nanotube(HNT),we propose a concept of lithium-ion dynamic interface(Li^(+)-DI)engineering in nano-charged CPE(NCCPE).Results show that the surface charge characteristics of HNTs fundamentally change the Li^(+)-DI,and thereof the mechanical and ion-conduction behaviors of the NCCPEs.Particularly,the HNTs with positively charged surface(HNTs+)lead to a higher Li^(+)transference number(0.86)than that of HNTs-(0.73),but a lower toughness(102.13 MJ m^(-3)for HNTs+and 159.69 MJ m^(-3)for HNTs-).Meanwhile,a strong interface compatibilization effect by Li^(+)is observed for especially the HNTs+-involved Li^(+)-DI,which improves the toughness by 2000%compared with the control.Moreover,HNTs+are more effective to weaken the Li^(+)-solvation strength and facilitate the formation of Li F-rich solid-electrolyte interphase of Li metal compared to HNTs-.The resultant Li|NCCPE|LiFePO4cell delivers a capacity of 144.9 m Ah g^(-1)after 400 cycles at 0.5 C and a capacity retention of 78.6%.This study provides deep insights into understanding the roles of surface charges of nanofillers in regulating the mechanical and electrochemical interfaces in ASSLMBs. 展开更多
关键词 Charged nanofillers Nanocomposite polymer electrolyte Dynamic lithium ion interface Solid ion-conductors Solidstate lithium-metal battery
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Harnessing S-scheme junctions for enhanced CO_(2) photoreduction:molecular bonding of copper(Ⅱ)complexes onto K-doped polymeric carbon nitride via microwave heating 被引量:2
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作者 Ming-Yu Heng Hong-Lei Shao +5 位作者 Jie-Ting Sun Qian Huang Shu-Ling Shen Guang-Zhi Yang Yu-Hua Xue Shu-Ning Xiao 《Rare Metals》 2025年第2期1108-1121,共14页
Photocatalytic conversion of CO_(2) is pivotal for mitigating the global greenhouse effect and fostering sustainable energy development.Nowadays,polymeric carbon nitride(PCN)has gained widespread application in CO_(2)... Photocatalytic conversion of CO_(2) is pivotal for mitigating the global greenhouse effect and fostering sustainable energy development.Nowadays,polymeric carbon nitride(PCN)has gained widespread application in CO_(2) solar reduction due to its excellent visible light response,suitable conduction band position,and good cost-effectiveness.However,the amorphous nature and low conductivity of PCN limit its photocatalytic efficiency by leading to low carrier concentrations and facile electron–hole recombination during photocatalysis.Addressing this bottleneck,in this study,potassium-doped PCN(KPCN)/copper(Ⅱ)-complexed bipyridine hydroxyquinoline carboxylic acid(Cu(Ⅱ)(bpy)(H_(2)hqc))composite catalysts were synthesized through a multistep microwave heating process.In the composite,the formation of an S-scheme junction facilitates the enrichment of more negative electrons on the conduction band of KPCN via intermolecular electron–hole recombination between Cu(Ⅱ)(bpy)(H_(2)hqc)(CuPyQc)and KPCN,thereby promoting efficient photoreduction of CO_(2) to CO.Microwave heating enhances the amidation reaction between these two components,achieving the immobilization of homogeneous molecular catalysts and forming amidation chemical bonds that serve as key channels for the S-scheme charge transfer.This work not only presents a new PCN-based catalytic system for CO_(2) reduction applications,but also offers a novel microwave-practical approach for immobilizing homogeneous catalysts. 展开更多
关键词 Photocatalytic CO_(2)reduction Microwave synthesis polymeric carbon nitride Amide bond Sscheme
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Polymer-assisted soybean crude urease carbonate precipitation technique for soil improvement
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作者 Zalfa Maulida Ihsani Naoki Kinoshita +1 位作者 Hideaki Yasuhara Heriansyah Putra 《Biogeotechnics》 2025年第4期27-42,共16页
This study presents a sustainable approach to soil improvement by integrating polyvinyl alcohol(PVA)into the Soybean Crude Urease Carbonate Precipitation(SCU-CP)technique.The research aims to enhance SCU-CP,which util... This study presents a sustainable approach to soil improvement by integrating polyvinyl alcohol(PVA)into the Soybean Crude Urease Carbonate Precipitation(SCU-CP)technique.The research aims to enhance SCU-CP,which utilizes soybean-derived urease to precipitate calcium carbonate,bonding soil particles and increasing strength.Challenges such as low solution viscosity and inconsistent carbonate precipitation are addressed by incorporating PVA,a biodegradable polymer that improves viscosity and retention.Comprehensive evaluations reveal significant findings:increasing PVA concentration enhances solution viscosity and results in higher calcium carbonate precipitation.Water retention assessments show that the PCP-1%treatment increases saturation water content(w_(s))to 0.263 compared to 0.217 for untreated soil,while also reduces the air-entry value(α).Unconfined Compressive Strength(UCS)tests indicate substantial improvement for PCP-1%,achieving approximately 140 kPa,with values reaching 179 kPa after 28 days.Calcium carbonate content measurements reveal that SCU-CP exhibits a variable distribution(standard deviation of 1.13),while PCP-1%demonstrates a more uniform distribution(standard deviation of 0.60),indicating improved effectiveness.Durability assessments through wet-dry cycling show that SCU-CP experiences a mass loss of 36.5%,while PCP-1%retains only 5%mass loss and maintains a UCS values.SEM images indicate that SCU-CP forms spherical structures,whereas PCP-1%produces a more diverse and crystalline morphology,suggesting better nucleation and distribution.Overall,the polymer-assisted SCU-CP technique(PCP)demonstrates significant potential for effective soil improvement. 展开更多
关键词 carbonATES polymer Soil improvement UNIFORMITY
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Facilitated transport membranes in post-combustion carbon capture:Recent advancements in polymer materials and challenges towards practical application 被引量:1
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作者 Zihan Wang Zhien Zhang +1 位作者 Mohamad Reza Soltanian Ruizhi Pang 《Green Energy & Environment》 2025年第3期500-517,共18页
Facilitated transport membranes for post-combustion carbon capture are one of the technologies to achieve efficient and large-scale capture.The central principle is to utilize the affinity of CO_(2) for the carrier to... Facilitated transport membranes for post-combustion carbon capture are one of the technologies to achieve efficient and large-scale capture.The central principle is to utilize the affinity of CO_(2) for the carrier to achieve efficient separation and to break the Robson upper bound.This paper reviews the progress of facilitated transport membranes research regarding polymer materials,principles,and problems faced at this stage.Firstly,we briefly introduce the transport mechanism of the facilitated transport membranes.Then the research progress of several major polymers used for facilitated transport membranes for CO_(2)/N_(2) separation was presented in the past five years.Additionally,we analyze the primary challenges of facilitated transport membranes,including the influence of water,the effect of temperature,the saturation effect of the carrier,and the process configuration.Finally,we also delve into the challenges and competitiveness of facilitated transport membranes. 展开更多
关键词 Facilitated transport CO_(2)/N_(2)separation polymer materials Membrane stability
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Carbonized polymer dots:Illuminating synthesis pathways,optical frontiers,and photoelectronic breakthroughs
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作者 Weinan Hu Li Li +5 位作者 Xinyu Wang Yongqiang Zhang Maoping Song Linlin Shi Xinqi Hao Siyu Lu 《Chinese Chemical Letters》 2025年第11期143-156,共14页
Since the discovery of carbonized polymer dots(CPDs)two decades ago,this emerging family of carbonbased nanomaterials has rapidly risen to prominence.CPDs have found widespread applications in sensing,catalysis,energy... Since the discovery of carbonized polymer dots(CPDs)two decades ago,this emerging family of carbonbased nanomaterials has rapidly risen to prominence.CPDs have found widespread applications in sensing,catalysis,energy,and biomedicine due to their flexible precursors and synthesis methods,tunable photoluminescence(PL)properties,and excellent biocompatibility.This report presents the advancements made in the realm of CPD precursors,elucidates their luminescence properties and underlying mechanisms,and explores the diverse applications of CPD-based materials.It comprehensively addresses key issues by delving into several interconnected chapters:Initially exploring the intriguing fluorescence and afterglow properties exhibited by CPDs,subsequently unraveling the complex luminescence mechanisms that underlie these phenomena,emphasizing the crucial aspect of controllable synthesis of CPDs,and ultimately culminating in the precise construction of composite materials tailored for applications in laser and electroluminescent devices.Furthermore,this report aims to provide communication and assistance for the controlled synthesis and expanded applications of CPDs. 展开更多
关键词 carbonized polymer dots Precursors Optical properties Luminescence mechanisms Applications
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Modification of Maxwell model for conductivity prediction of carbon nanotubes-filled polymer composites with tunneling effect
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作者 Jue ZHU Longyuan LI Ningtao ZHU 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期25-36,共12页
Carbon nanotubes(CNTs)have garnered great attention in recent years due to their outstanding electrical,thermal,and mechanical properties.The incorporation of small amounts of CNTs in polymers can substantially improv... Carbon nanotubes(CNTs)have garnered great attention in recent years due to their outstanding electrical,thermal,and mechanical properties.The incorporation of small amounts of CNTs in polymers can substantially improve the sensitivity of the polymer's electrical conductivity.This paper presents a modified Maxwell model to evaluate the electrical conductivity of CNTs-filled polymer composites by introducing a transition zone to account for the tunneling effect.In this modified Maxwell model,the CNTs-filled polymer composite is modeled as a three-phase composite,consisting of a matrix(polymer),inclusions(CNTs),and a transition zone(tunneling zone).The effective electrical conductivity(EEC)of the composite is calculated based on the volume fractions and electrical conductivities of the matrix,inclusions,and transition zone.The model's validity is confirmed through the use of available test data,which demonstrates its capability to accurately capture the nonlinear conductivity behavior observed in CNTs-polymer composites.This study offers valuable insights into the design of high-performance conductive polymer nanocomposites,and enhances the understanding of electrical conduction mechanisms in CNT-dispersed polymer composites. 展开更多
关键词 carbon nanotube(CNT) polymer composite electrical conductivity TUNNELING Maxwell model
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Carbonized polymer dots confinned active Ru-O sites for boosting electrocatalytic oxygen evolution
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作者 Da Yue Tanglue Feng +5 位作者 Zhicheng Zhu Mingcheng Zhang Liyuan Chen Xiao Han Haizhu Sun Bai Yang 《Chinese Chemical Letters》 2025年第11期441-446,共6页
Designing efficient and stable electrocatalysts for the oxygen evolution reaction(OER)is of paramount importance for many energy-related technologies and devices.Herein,we propose a controlled oxidation pyrolysis stra... Designing efficient and stable electrocatalysts for the oxygen evolution reaction(OER)is of paramount importance for many energy-related technologies and devices.Herein,we propose a controlled oxidation pyrolysis strategy to develop carbonized polymer dots(CPDs)-modified Rh-doped RuO_(2)electrocatalyst(Rh-RuO_(2)/CPDs).CPDs act as structure-directing agents,facilitating the formation of small-sized RhRuO_(2)/CPDs nanoparticles and engineering them with abundant defective structures and stable Ru-O sites.The experimental results and theoretical simulation unravel that the modulation effect of CPDs and Rh doping can effectively regulate the electronic structure,valence state and morphology of active Ru-O sites,thereby enhancing the electron transfer at the active site interface and optimizing the chemisorption behavior of oxygen intermediates.The resultant Rh-RuO_(2)/CPDs demonstrates overpotentials of 168 and 197 mV at 10 mA/cm^(2)for OER in 0.5 mol/L H_(2)SO_(4)and 1.0 mol/L KOH solution,respectively,and longterm catalytic stability. 展开更多
关键词 carbonized polymer dots Confinement effect ELECTROCATALYSTS Oxygen evolution reaction Ruthenium dioxide Defect
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Molecular-based porous polymers with precise sites for photoreduction of carbon dioxide
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作者 Wei-Jia Wang Kaihong Chen 《Chinese Chemical Letters》 2025年第1期201-213,共13页
Photocatalytic CO_(2)reduction reaction(CO_(2)RR)is one of the promising strategies for sustainably producing solar fuels.The precise identification of catalytic sites and the enhancement of photocatalytic CO_(2)conve... Photocatalytic CO_(2)reduction reaction(CO_(2)RR)is one of the promising strategies for sustainably producing solar fuels.The precise identification of catalytic sites and the enhancement of photocatalytic CO_(2)conversion is imperative yet quite challenging.This critical review summarizes recent advances in porous photo-responsive polymers,including covalent organic frameworks(COFs),covalent triazine frameworks(CTFs),and conjugated microporous polymers(CMPs),those can be rationally designed from the molecular level for visible-light-driven photocatalytic CO_(2)reduction.Additionally,special emphasis is placed on how the well-defined active sites on these polymers can influence their properties and photocatalytic performance.The precise regulation and control of microenvironments and electronic properties of metal active centers are crucial for boosting catalytic efficiency and selectivity,as well as for the design of better photocatalysts for CO_(2)reduction. 展开更多
关键词 carbon dioxide reduction PHOTOCATALYSIS Porous polymers Well-defined catalytic sites Molecular level
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Structural optimization of carbonized polymer dots for modulation of electrochemical performance of aqueous electrolytes
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作者 HUANG Xinyao WANG Jiahui +2 位作者 YANG Guoduo JI Xin SUN Haizhu 《分子科学学报》 2025年第2期14-20,共7页
Aqueous zinc ion batteries(AZIBs)are considered to be one of the most promising energy storage devices due to the advantages of high cost-effectiveness,safety,and environmental friendliness.However,they suffer from pr... Aqueous zinc ion batteries(AZIBs)are considered to be one of the most promising energy storage devices due to the advantages of high cost-effectiveness,safety,and environmental friendliness.However,they suffer from problems such as Zn dendrites growth and by-product generation.Carbonized polymer dots(CPDs)with polar groups as additive have been introduced to modulate the solvated structure of Zn^(2+)and reduce the water activity,promoting the uniform deposition of Zn and inhibiting the occurrence of side reactions.However,CPDs with different functional group contents from different precursor molar ratios variably affect the electrochemical performance of aqueous electrolytes.Therefore,in this work,we designed and synthesized CPDs with different molar ratios of the precursors(citric acid and urea)as electrolyte additives for AZIBs and explore the optimal molar ratios of the precursors.The Zn//Zn symmetrical cells using electrolytes with the optimal ratios CPDs achieve an extended cycle life over 615 h at 2 mA∙cm^(−2) and 1 mAh∙cm^(−2).This work offers great potential for future practical applications of CPDs. 展开更多
关键词 Zn metal anode Electrolyte additive carbonized polymer dots Zn dendrites
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Electrostatic Attraction-Driven Assembly of Non-Noble Metallo-Supramolecular Polymers With Single-Walled Carbon Nanotubes for Boosting Photocatalytic Hydrogen Evolution
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作者 Yanyan Qin Chen Zhang +2 位作者 Yidi Wang Pengfei She Wai-Yeung Wong 《Carbon Energy》 2025年第6期110-119,共10页
The search for photoactive materials that are able to efficiently produce solar fuels is a growing research field to tackle the current energy crisis.Herein,we have prepared two ionic non-noble metallo-supramolecular ... The search for photoactive materials that are able to efficiently produce solar fuels is a growing research field to tackle the current energy crisis.Herein,we have prepared two ionic non-noble metallo-supramolecular polymers Se-MTpy(M=Co or Ni),and constructed their composites with single-walled carbon nanotubes(CNTs)via electrostatic attraction andπ-πinteractions for efficient and stable photocatalytic hydrogen evolution.In the photocatalytic system,the cationic Se-MTpy as host and anionic CNTs as vip are assembled into a binary composite,which exhibits superior photocatalytic activity under visible light irradiation(>420 nm).The optimized CNT@Se-CoTpy composite,containing 1.2 wt%metal loading,achieves 7 times higher hydrogen evolution rate(2.47 mmol g^(-1)h^(-1))than bare Se-CoTpy(0.35 mmol g^(-1)h^(-1)).This is attributed to the constructive formation of junctions between polymer and CNTs,facilitating interfacial charge transfer and transport for efficient proton reduction.The composite system also shows high photostability after continuous irradiation for~30 h.The combination of experimental and theoretical analysis demonstrates the higher activity for reducing H_(2)O to H_(2)of Se-CoTpy than Se-NiTpy.The feasible interfacial architecture proposed in this study represents an effective approach to achieve high photocatalytic performance. 展开更多
关键词 electrostatic attraction hybrid heterojunction metallo-supramolecular polymers photocatalytic hydrogen evolution single-walled carbon nanotubes
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Application of Carbon Fiber Reinforced Polymer in Bridge Reinforcement
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作者 Yuwei Zhang 《Journal of Architectural Research and Development》 2025年第3期76-80,共5页
Carbon fiber reinforced polymer(CFRP)is an advanced material widely used in bridge structures,demonstrating a promising application prospect.CFRP possesses excellent mechanical properties,construction advantages,and d... Carbon fiber reinforced polymer(CFRP)is an advanced material widely used in bridge structures,demonstrating a promising application prospect.CFRP possesses excellent mechanical properties,construction advantages,and durability benefits.Its application in bridge reinforcement can significantly enhance the overall performance of the reinforced bridge,thereby improving the durability and extending the service life of the bridge.Therefore,it is necessary to further explore how CFRP can be effectively applied in bridge reinforcement projects to improve the quality of such projects and ensure the safety of bridges during operation. 展开更多
关键词 carbon fiber reinforced polymer Earthquake resistance Bridge reinforcement design
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Coordination polymer derived transition metal phosphide/carbon composites for bifunctional oxygen electrocatalyst
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作者 Yue Du Zhiyi Zhong +8 位作者 Lina Zhou Wenxue Chen Zhixian Shi Pan Song Yifeng Liu Yao Yao Yisi Liu Shixue Dou Yao Xiao 《Journal of Materials Science & Technology》 2025年第19期142-151,共10页
Developing nonprecious electrocatalysts with bifunctional performances for oxygen reduction(ORR)and evolution reactions(OER)remains a crucial challenge in rechargeable Zn-air batteries(RZABs).In this study,we report t... Developing nonprecious electrocatalysts with bifunctional performances for oxygen reduction(ORR)and evolution reactions(OER)remains a crucial challenge in rechargeable Zn-air batteries(RZABs).In this study,we report the synthesis of a three-dimensional(3D)porous N,P-doped carbon-wrapped cobalt phosphide composite(Co2P@3DNPC)via direct calcination of a novel organic/inorganic porous coordi-nation polymer by an in-situ phosphating strategy.DFT calculations demonstrate the intricate interac-tions occurring during the PEI-directed grinding self-assembly process among Co^(2+),phytic acid(PA),and polyethylenimine(PEI).Specifically,Co^(2+)ions initially adsorb onto PEI molecules before integrating with PA to form a 3D coordination polymer matrix.As-fabricated Co2P@3DNPC composite exhibits impressive ORR/OER bifunctional performances,with a half-wave potential of 0.78 V and an overpotential of 1.71 V,respectively.Its bifunctional activities enable a power density of 148.5 mW cm^(-2)in rechargeable ZABs,with remarkable stability(>480 h)during a discharge-charge cycle.The interconnected porous structure and embedded Co2P nanoparticles optimize the electrode-electrolyte interfacial contact,boosting energy density and cycle life of as-assembled ZABs.This innovative approach paves the way for efficient,cost-effective production of bifunctional electrocatalysts for RZABs. 展开更多
关键词 Transition metal phosphides Bifunctional electrocatalyst Coordination polymer Three-dimensional porous carbon Rechargeable Zn-air battery
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