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Recent advances in porous structures for oxygen reduction reaction

Progress in Natural science:materials International 2025年第1期35卷 83-97页

作者： Ying Chen Huawei Wang Yujing Li Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications.School of Materials Science and Engineering Beijing Institute of Technology Fuel Cell Products Business Weichai Power Company Limited

As environmental concerns grow, there is a global shift from traditional fossil energy. Hydrogen fuel cells are gaining attention, but high material costs limit their adoption in large scale. The oxygen reduction reaction at the cathode of fuel cell, which dominates the electrochemical kinetics, relies mainly on platinum-group-metal(PGM) catalysts, hence research is focused on minimizing PGM or developing non-PGM catalysts. Porous materials possess unique physicochemical properties, and have shown great potential in advancing catalyst technology in fuel cells. This review summarizes the recent fundamental and technological advances of porous catalysts for oxygen reduction reactions including PGM and non-PGM catalysts, discusses the mechanisms underlying the enhanced catalytic activity through structural design and surface modification. It also highlights the comprehensive impact of porous materials in oxygen reduction reactions and membrane electrode assemblies,the main challenges, and provides perspectives on research of porous catalyst.

关键词： Oxygen reduction reaction

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Stabilized interfacial structure induced by self-dissolved active atoms in the (HfZrTiTaNb)C high-entropy carbide brazed joint using CoCrFeNi alloy

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Ceramics International 2025年第15期51卷 20006-20015页

作者： Mu, Ruijie Wang, Ying Niu, Shiyu Sun, Kongbo Yang, Zhenwen Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and Engineering Tianjin University Tianjin300350 China Key Laboratory of Advanced Ceramics and Machining Technology Ministry of Education Tianjin300350 China

Understanding reaction behavior of the high-entropy solid/liquid interface induced by multicomponent dissolution is critical for the construction of reliable brazed joints for high-temperature service. The brazed joint of (HfZrTiTaNb)C high-entropy carbide (HEC) bonded with a simple CoCrFeNi high-entropy alloy was investigated at 1440–1550 °C for 15–60 min. Under bonding temperatures, HEC grains dissociated into the liquid alloy, and the self-dissolved Zr atoms at the interface between the HEC grains and liquid alloy induced the formation of Zr-riched HEC phase (ZHEC) attached to HEC grains. The ZHEC phases were characterized by the increased Zr content to 21.44 at.% and the coherent orientation with the HEC. The CoCrFeNi alloy did not undergo phase separation after solidifying in the middle of the joint, resulting in a high-entropy interfacial structure, which remained stabilized in the joints over a wide range of process parameters. In addition, the shear strength and high-temperature performance of the joints were evaluated. A joint strength of 266 MPa could be obtained when brazed at 1460 °C for 45 min. At an test temperature of 1000 °C, the joint strength still retained 87 MPa, indicating its positive potential for high-temperature applications. Intergranular fracture of the CoCrFeNi under elevated temperatures was responsible for the decrease in joint strengths. © 2025 Elsevier Ltd and Techna Group S.r.l.

关键词： Cobalt alloys

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Custom-assembled phase change modular devices for personalize speciality:Carbon energy thermal management application

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Nano Research 2025年第3期18卷 22-32页

作者： Yilin Chen Huitao Yu Yiyu Feng Wei Feng School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300350China Institute of Advanced Technology and Equipment Beijing University of Chemical TechnologyBeijing 100029China

In the context of 5G,the high-frequency cyclicity and inhomogeneity of heat flow put forward higher requirements for the thermal control system of electronic devices,and there is a great need for thermal management modules with fixed point and high efficiency to ensure the long-term development of electronic ***,we selected four phase change molecules with significant differences in phase change temperatures to be composited with graphene aerogel(GA)to obtain Ei@GA,Tetra@GA,Octa@GA,and 1,10-Deca@*** with pure phase change molecules,the thermal conductivity has been increased by more than 20%,and the relative enthalpic efficiency is as high as 98.7%or ***,we assembled the four phase change composites by“reduction welding”to obtain the integrated,modular thermal management device M1-PCMs@*** of inhomogeneous heat generation in electronics by building an inhomogeneous heat generation *** with the homogeneous modules M2-Ei@GA and M3-1,10-Deca@GA,the effective temperature control time of the customized module M1-PCMs@GA is extended by 100.0 and 394.3 s,***,custom-assembled modular thermal management devices have important application prospects in the field of intelligent temperature control of electronic devices,and the idea of cascade assembly enriches the application functions and development direction of intelligent thermal managers.

关键词： graphene aerogel phase change materials assembly customization modular thermal management devices

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Microstructure,microchemistry,and micro-magnetism of dysprosium grain boundary diffused(Nd,Ce)-Fe-B magnets

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Journal of Rare Earths 2025年第3期43卷 556-568,I0005页

作者： Yifei Xiao Lele Zhang Tao Liu Qisong Sun Xiaolong Song Yikun Fang Anhua Li Minggang Zhu Wei Li Division of Functional Materials Central Iron and Steel Research InstituteBeijing 100081China Key Laboratory of Advanced Functional Materials Ministry of Education of ChinaCollege of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124China

The microstructure of(Nd,Ce)-Fe-B sintered magnets with different diffusion depths was characterized by a magnetic force microscope,and the relationship between the magnetic properties and the local structure of grain boundary diffused magnets is *** domains perpendicular to the c-axis(easy magnetization direction)show a typical maze-like pattern,while those parallel to the c-axis show the characte ristics of plate *** significant gradient change is shown in the concentration of Dy with the direction of diffusion from the surface to the *** diffuses along grain boundaries and(Dy,Nd)_(2)Fe_(14)B layer with a high anisotropy field formed around the *** in-situ electron probe micro-analysis/magnetic force microscopy(EPMA/MFM),it is found that the average domain width decreases,and the proportion of single domain grains increases as diffusion depth *** is caused by both the change of concentration and distribution of *** grain boundary diffusion process changes the microstructure and microchemistry inside the magnet,and these local magnetism differences can be reflected by the configuration of the magnetic domain structure.

关键词： Magnetic microstructures (Nd,Ce)-Fe-B Rare earths Magnetic force microscope Grain boundary diffusion process(GBDP) In-situ

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Crystalline@amorphous core-shell structure of WO3@WO_(3-x)S_(x) established via doping strategy for enhancing magnesium ions storage performance

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Journal of Magnesium and Alloys 2025年第3期13卷 1353-1363页

作者： Shiqi Ding Yuxin Tian Jiankang Chen Guofeng Wang Bing Sun He Lv Lei Wang Guicun Li Alan Meng Zhenjiang Li College of Materials Science and Engineering Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life ScienceMOEShandong Key Laboratory of Biochemical AnalysisCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042ShandongPR China Qingdao Engineering Research Center for New Metallic Functional Materials Characteristic Laboratory of Advanced Metal Functional Materials and Processing in Universities of ShandongQingdao Binhai UniversityQingdao 266555ShandongPR China

Designing cathode possessing crystalline@amorphous core-shell structure with both active core and shell is a meaningful work for resolving the low speciﬁc capacity,unstable cycling performance and sluggish reaction kinetics issues of rechargeable magnesium batteries(RMBs)by providing more active sites as well as releasing inner stress during ***,WO_(3)@WO_(3-x)S_(x) owning crystalline@amorphous core-shell structure containing both active core and active shell is constructed successfully by introducing S into metastable WO3 structure under temperatureﬁeld *** such structure,amorphous shell would provide continuous Mg^(2+)diffusion channels due to its isotropy property for most Mg^(2+)migrating rapidly to interface and then adsorb at ions reservoir formed by interfacial electricﬁeld for increasing speciﬁc *** also makes security for stable structure of WO_(3)@WO_(3-x)S_(x) by alleviating volume expansion of crystalline core WO_(3) during cycling to prolong cycling ***,“softer”ions S^(2-)would weaken interaction between hard acid Mg^(2+) and ionic lattice to enhance Mg^(2+)storage ***,WO_(3)@WO_(3-x)S_(x) delivers the superior cycling performance(1000 cycles with 83.3%),rate capability(88.5 mAh g^(-1) at 1000 mA g^(-1))and speciﬁc capacity(about 150 mAh g^(-1) at 50 mA g^(-1)),which is near 2 times higher than that of *** is believed that the crystalline@amorphous core-shell structure with both active core and shell designing via doping strategy is enlightening for the development of high-performance RMBs,and such design can be extended to other energy storage devices for better electrochemical performance.

关键词： Doping Sulfuration Crystalline@amorphous core-shell structure WO_(3) Rechargeable magnesium batteries

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Novel titanium vanadate with superior Na^(+) transport kinetics for rapid charging and low-temperature sodium ion batteries

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Green Energy & Environment 2025年第2期10卷 374-381页

作者： Dan Lv Liehao Wei Cheng Wang Mingyue Wang Zhongchao Bai Yameng Fan Dongdong Wang Nana Wang Jian Yang Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) School of Materials Science and EngineeringTianjin UniversityTianjin300072China Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShandong UniversityJinan250100China Tianjin Key Lab of Indoor Air Environmental Quality Control School of Environmental Science and TechnologyTianjin UniversityTianjin300072China Institute for Superconducting and Electronic Materials University of WollongongWollongongAustralia Institute of Energy Materials Science(IEMS) University of Shanghai for Science and Technology516 Jungong RoadShanghai200093China

Sodium-ion batteries(SIBs)hold great promise for large-scale energy storage in the post-lithium-ion battery era due to their high rate performance and long lifespan,although their sluggish Na^(+) transformation kinetics still require *** by the excellent electrochemical performance of titanium-based anode materials,here,we present a novel titanium vanadate@carbon(TVO@C)material as anode for *** TVO@C material is synthesized via a facile coprecipitation method,with the following annealing process in an acetylene *** opened ion channel and the oxygen vacancies within TVO@C facilitate the diffusion of Na^(+) ions,reducing their diffusion ***,an ultrahigh rate of 100 A g^(-1)and long life of 10,000 cycles have been ***,the TVO@C electrode exhibits stable performance,not only at room temperature,but also at temperatures as low as 20 *** TVO@CjjNa_(3)V_(2)(PO_(4))_(3)@C full cells have also achieved stable discharge/charge for 500 *** is believed that this strategy provides new insight into the development of advanced electrodes and provides a new opportunity for constructing novel high rate electrodes.

关键词： Anode High rate Titanium vanadate Sodium ion batteries

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Unraveling the impacts of intermolecular interaction on morphology evolution for highly efficient organic solar cells and modules

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science China Chemistry 2025年第1期68卷 264-272页

作者： Xueqing Ma Yingying Cheng Yuqiang Liu Xinming Zheng Guangliu Ran Hongxiang Li Xinyue Cui Andong Zhang Wenkai Zhang Pei Cheng Wenchao Huang Zhishan Bo Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China College of Textiles and Clothing State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao 266071China Key State Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Department of Physics and Applied Optics Beijing Area Major Laboratory Center for Advanced Quantum StudiesBeijing Normal UniversityBeijing 100875China State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China

Understanding the effect of intermolecular interaction on the growth dynamic of active layers is critical for advancing organic solar cells(OSCs).However,the diverse structure of donors and acceptors makes the research *** with customizable structures and properties could simplify this ***,we meticulously tailor two additives of 3,4-ethylenedioxythiophene(EDOT)and 2,5-dibromo-3,4-ethylenedioxythiophene(DBEDOT),possessing distinct intermolecular interaction features to elaborate the inherent *** is found that varied interaction strengths can alter film formation *** enhanced intermolecular interaction between the DBEDOT and non-fullerene acceptor BTP-e C9-4F results in pre-aggregation and longer crystallization duration of BTP-e C9-4F,facilitating the formation of films with compact molecular packing and decent phase ***,exciton dissociation and charge transport become more ***,devices processed with DBEDOT exhibit a remarkable power conversion efficiency of 19.35%in small-area OSCs and 14.11%in bladecoated 5 cm×5 cm organic solar ***,OSCs can maintain 80%of their initial efficiency after continuous annealing at 85℃for over 2,100 h.

关键词： organic solar cell non-fullerene acceptor film growth molecular packing intermolecular interaction

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Precipitation Behavior of MnS Inclusion in Unidirectionally-solidified Fe–18Mn–1Al–0.3C Steels

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Tetsu-To-Hagane/Journal of the Iron and Steel Institute of Japan 2025年第3期111卷 122-130页

作者： Fan, Yuewen Kameda, Kouki Hu, Xiaojun Matsuura, Hiroyuki State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing China Department of Materials Engineering Graduate School of Engineering The University of Tokyo Japan

In order to reasonably control the precipitation of inclusions during solidification in TWIP steels, the precipitation behavior of typical MnS inclusions in high manganese steel was investigated by unidirectional solidification experiments. Through the combined analyses using ASEM-EDS, optical microscope, and thermodynamic calculation, it was found that Mn concentration in the liquid metal region were higher than those in the solid metal region. Furthermore, closer to the inclusion the liquid phase was, higher its Mn content was. In Fe–18mass%Mn–1Al–0.3C, MnS inclusions can precipitate at the positions located in the junction of dendrites at the end of the solidification (solid fraction fS = 0.96), Mn content reaching 34.88 mass%. Already existing Al2O3 particles could become the core of MnS to form composite inclusions to promote the MnS precipitation during the solidification process. When fS achieved 0.7 leading the Mn segregation in the liquid phase to 25 mass%, MnS starts to precipitate to attach the Al2O3 surface to form composite inclusion. © 2025 The Iron and Steel Institute of Japan.

关键词： Manganese steel

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Cr doping modification for tribological behavior of Cr/a-C multilayer coatings against PEEK under diverse operational conditions

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Friction 2025年第3期13卷 117-126页

作者： Xiaohui Zhou Yingpeng Zhang Hao Li Li Cui Wei Yang Aiying Wang Peng Guo Peiling Ke Key Laboratory of Advanced Marine Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

Considering the increasing demand for wearresistant materials used for various frictions with dynamic sealing parts,we employed hybrid magnetron sputtering technology to fabricate Cr/amorphous carbon(a-C)multilayered coatings with and without Cr doping for *** tribological behaviors of coatings paired with polyether ether ketone(PEEK)balls were investigated under different friction environments,including an evolving atmosphere,a NaCl solution,polyalphaolefin(PAO)oil,and water-in-oil(W/O).The results demonstrated that the tribological properties of all friction pairs were strongly influenced by the surrounding *** the atmosphere and in a NaCl solution,the addition of Cr promoted the formation of a-C-containing transfer films,thereby yielding stable and low friction ***,the dominant factor contributing to the tribological performance shifted from the coatings themselves to the PAO oil film with PAO *** the case of the W/O solution,both the facile reactivity of Cr and the intrinsic instability of the W/O mixture accelerated the presence of Cr_(2)O_(3),which caused more severe *** current observations not only identified the tribological failure mechanism of Cr/a-C coatings with and without Cr doping modifications in conjunction with their PEEK counterparts but also addressed the importance of designing and fabricating adaptive lubricant coatings for harsh multi-environment applications.

关键词： polyether ether ketone(PEEK) amorphous carbon polyalphaolefin(PAO)oil dynamic sealing tribo-chemistry

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Investigation of a GER damper using the Cut submode for vibration suppression in rotor systems with transmission shafts

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science China Technological sciences 2025年第5期68卷 78-90页

作者： Xijun CAO Jinglei ZHAO Zhi SUN Huajun CAO Xiaoxu HUANG Jun LUO Huayan PU The State Key Laboratory of Mechanical Transmission for Advanced Equipments Chongqing University College of Mechanical and Vehicle Engineering Chongqing University College of Materials Science and Engineering Chongqing University School of Mechatronics Engineering and Automation Shanghai University

Electrorheological（ER） and magnetorheological（MR） dampers, which are active damping devices, stand out for their exceptional performance in mitigating vibrations in mechanical systems and construction engineering. Their prowess lies in the inherent ability of ER/MR fluids to change their mechanical properties, particularly viscosity and shear stress, in response to the influence of electric or magnetic fields. In this study, a damper filled with Giant-ER（GER） fluid, a modified product of ER fluid,is employed in the rotor system for vibration suppression. This damper operates in a Cut submode derived from the conventional working modes. This mode results in an effective enhancement of the damping performance by integrating the advantages of these modes, thereby achieving a damping force density of 1.2 × 10～4 N/m2and a modulation coefficient of 15 within a multilayered cylindrical damper. Whereafter, the dynamics of the rotor system are modeled and analyzed based on the Jeffcott rotor model, which incorporates a parallelogram-structured motion decoupling mechanism equipped with the proposed Cut submode dampers that are introduced to reduce the vibration of the transmission shaft in the rotor system. Furthermore, to evaluate the damping effect, a vibration-damping performance validation testbed is constructed. The results are noteworthy, demonstrating that by leveraging the superior properties of the GER fluid, the Cut submode damper effectively suppresses the vibrations of the transmission shaft, particularly at the resonant frequencies, achieving an impressive 88.9% reduction when subjected to an electric field of 3 kV/mm compared to the action of 0 kV/mm. This performance highlights the exceptional effectiveness of the proposed Cut submode, underscoring its vast potential for various engineering applications.

关键词： transmission shaft vibration suppression giant electrorheological fluid fluid damper Cut submode

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