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Nickel Sulfide Modified NiCu Nanoalloy with Excellent Oxygen Evolution Reaction Properties Prepared through Electrospinning and Heat Treatment

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Journal of Wuhan University of Technology(materials Science) 2024年第2期39卷 320-326页

作者：李涛凌帅 ZHONG Shujie LOU Qiongyue Department of materials engineering School of Mechanical EngineeringChengdu UniversityChengdu 610106China

Ni^(2+)/Cu^(2+)/SO_(4)^(2-)/polyvinyl alcohol precursor fibers with uniform diameters were prepared through ***-based composite nanoalloys containing Ni,Cu,and S were prepared through heat treatment in an Ar *** experimental results show that the main components of the prepared nanoalloys are NiCu,Ni_(3)S_(2),Ni,and *** nanoalloys exhibit fine grain sizes about 200-500 nm,which can increase with increasing heat treatment *** test results show that the nickel sulfidemodified NiCu nanoalloy composites exhibit excellent oxygen evolution reaction properties,and the oxygen evolution reaction properties gradually improve with the increasing heat treatment *** sample prepared at 1 000℃ for 40 min show a low overpotential of 423 mV and a small Tafel slope of 134 mV·dec^(-1) at a current density of 10 mA·cm^(-2).

关键词： NiCu nanoalloy Ni_(3)S_(2) structure transformation oxygen evolution reaction

Numerical simulation on the multiphase flow and reoxidation of the molten steel in a two-strand tundish during ladle change

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International Journal of Minerals,Metallurgy and materials 2024年第7期31卷 1540-1553页

作者： Jingcheng Wang Zhentong Liu Wei Chen Hongliang Chen Lifeng Zhang School of mechanical engineering Yanshan UniversityQinhuangdao 066004China School of materials Science and engineering Tianjin UniversityTianjin 300350China School of mechanical and materials engineering North China University of TechnologyBeijing 100144China

A 3D mathematical model was proposed to investigate the molten steel–slag–air multiphase flow in a two-strand slab continuous casting(CC)tundish during ladle *** study focused on the exposure of the molten steel and the subsequent reoxidation *** exposure of the molten steel was calculated using the coupled realizable k–εmodel and volume of fluid(VOF)*** diffusion of dissolved oxygen was determined by solving the user-defined scalar(UDS)***,the user-defined function(UDF)was used to describe the source term in the UDS equation and determine the oxidation rate and oxidation *** effect of the refilling speed on the molten steel exposure and dissolved oxygen content was also *** the refilling speed during ladle change reduced the refilling time and the exposure duration of the molten ***,the elevated refilling speed enlarged the slag eyes and increased the average dissolved oxygen content within the tundish,thereby exacerbating the reoxidation *** addition,the time required for the molten steel with a high dissolved oxygen content to exit the tundish varied with the refilling *** the inlet speed was 3.0 m·s^(-1)during ladle change,the molten steel with a high dissolved oxygen content exited the outlet in a short period,reaching a maximum dissolved oxygen content of 0.000525wt%.Conversely,when the inlet speed was 1.8 m·s^(-1),the maximum dissolved oxygen content was 0.000382wt%.The refilling speed during the ladle change process must be appropriately decreased to minimize reoxidation effects and enhance the steel product quality.

关键词： tundish ladle change reoxidation multiphase flow numerical simulation

Recent Advances in Asymmetric Structural Composites for Excellent Electromagnetic Interference Shielding: A Review

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Chinese Journal of Polymer Science 2024年第6期42卷 693-710页

作者： Ying Zhou Bai Xue Lan Xie Chang-Mei Wu Qiang Zheng Department of Polymer materials and engineering College of Materials and Metallurgy Guizhou University National engineering Research Center for Compounding and Modification of Polymer materials National and Local Joint Engineering Research Center for Functional Polymer Membrane Materials and Membrane Processes State Key Laboratory of Public Big Data Guizhou University Department of Polymer Science and engineering Zhejiang University

Since electromagnetic pollution is detrimental to human health and the environment, numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE) via designing the hierarchical structures for electromagnetic interference(EMI) shielding polymer composites. Among the plentiful structures, the asymmetric structures are currently a hot spot, principally categorizing into multi-layered, porous, fibrous, and segregated asymmetric structures, which endows the high EMI shielding performance for polymer composites incorporated with magnetic, conductive, and/or dielectric micro/nano-fillers, due to the “absorption-reflection-reabsorption” shielding mechanism. Therefore, this review provides the retrospection and summary of the efforts with respect to abundant asymmetric structures and multifunctional micro/nano-fillers for enhancing EMI shielding properties, which is conducive to the booming development of polymeric EMI shielding materials for the promising prospect in modern electronics and 5-generation(5G) technology.

关键词： Asymmetric structure Microano functional filler Polymer composite Electromagnetic interference shielding

Design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

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Journal of Magnesium and Alloys 2024年第4期12卷 1461-1478页

作者： Zohra Benzarti Sandesh Itani JoséDavid Castro Sandra Carvalho Ana Sofia Ramos University of Coimbra CEMMPREARISEDepartment of Mechanical EngineeringRua Luís Reis Santos3030-788CoimbraPortugal Laboratory of Multifunctional materials and Applications(LaMMA) Department of PhysicsFaculty of Sciences of SfaxUniversity of SfaxSoukra Road km 3.5B.P.1171Sfax3000Tunisia

Magnesium(Mg)alloys are widely used for temporary bone implants due to their favorable biodegradability,cytocompatibility,hemocompatibility,and close mechanical properties to ***,rapid degradation and inadequate strength limit their *** overcome this,the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium(Zr)*** approach presents a promising strategy for simultaneously improving corrosion resistance,maintaining biocompatibility,and enhancing strength without compromising *** leveraging Mg’s inherent biodegradability,it has the potential to minimize the need for secondary surgeries,thereby reducing costs and *** paper is a systematic study aimed at understanding the corrosion mechanisms of Mg–Zr coatings,denoted Mg-xZr(x=0–5 at.%).Zr-doped coatings exhibited columnar growth leading to denser and refined structures with increasing Zr *** analysis confirmed the presence of the Mg(00.2)basal plane,shifting towards higher angles(1.15°)with 5 at.%Zr doping due to lattice parameter changes(i.e.,decrease and increase of“c”and“a”lattice parameters,respectively).Mg–Zr coatings exhibited“liquidphilic”behavior,while Young’s modulus retained a steady value around 80 GPa across all ***,the hardness has significantly improved across all samples’coating,reaching the highest value of(2.2±0.3)GPa for 5 at.%*** testing in simulated body fluid(SBF)at 37℃ revealed a significant enhancement in corrosion resistance for Mg–Zr coatings containing 1.0–3.4 at.%*** with the 5 at.%Zr coating which exhibited a corrosion rate of 32 mm/year,these coatings displayed lower corrosion rates,ranging from 1 to 12 mm/*** synergistic enhancement in mechanical properties and corrosion resistance,achieved with 2.0–3.4 at.%Zr,suggests potential ability for reducing stress shielding and controlled degradation performance,and consequentl

关键词： Mg-Zr coatings Magnetron sputtering Nanoindentation Corrosion resistance Bone implants

Applying the Protective Mn-Co-La_(2)O_(3)Coating on Crofer 22 APU Ferritic Stainless Steel Used as Solid Oxide Fuel Cell Interconnects

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 872-888页

作者： Farhad Mohsenifar Hadi Ebrahimifar Ahmad Irannejad Department of materials engineering and Metallurgy Faculty of EngineeringShahid Bahonar University of KermanKermanIran mechanical engineering Department Faculty of EngineeringHigher Education Complex of Bam76615-314BamIran Department of materials engineering Faculty of Mechanical and Materials EngineeringGraduate University of Advanced TechnologyKerman ***Iran

This research studies the effect of Mn-Co-La_(2)O_(3) coating synthesized by the electrodeposition method on the oxidation resistance and electrical conductivity of the Crofer 22 APU stainless steel interconnect plates in solid oxide fuel *** test samples were characterized by a field emission scanning electron microscope(FESEM)equipped with energy dispersive spectroscopy(EDS),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The oxidation kinetics of the coated and uncoated samples were studied by tracking their weight changes over time at 800°C,showing that the oxidation mechanism for all samples follows the parabolic *** oxidation rate constant(k_(p))values of the coated sample compared with that of the uncoated one indicated a reduction in the oxidation rate of the steel substrate in the presence of the Mn-Co-La_(2)O_(3) *** examination of the cross-section of different samples after the isothermal oxidation for 500 h at 800°C exhibited that applying the composite coating leads to a decrease in the thickness of the chromia layer formed on the steel ***,under these conditions,the area-specific resistance(ASR)of the coated sample(13.11 mΩcm^(2))is significantly lower than that of the uncoated one(41.45 mΩcm^(2)).

关键词： Area specific resistance Oxidation Fuel cell Composite coating

A generalized presentation of multi-caloric effects based on exterior derivative theory and its applications

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Communications in Theoretical Physics 2024年第08期76卷 158-165页

作者： Jun Yin School of materials Science and engineering Nankai University School of mechanical engineering and Automation Fuzhou University

The emerging concept of multi-caloric effects, introduced in 2010, entails the application of multiple interplay fields to a thermodynamic system. While multi-caloric effects are the main focus of experimental endeavors, theoretical considerations fall short of providing a thorough understanding. This paper introduces a comprehensive presentation on multi-caloric effects,employing the method and theory of exterior derivative formations. It addresses every aspect of thermodynamic systems, showcasing its applicability to multi-caloric materials(both singlephase and multi-phase materials), and its adaptability to different scenarios(either in single or multiple force fields). The formulation of Maxwell relationships, characterized by their generality and universality, enables a clear prediction in entropy and temperature, facilitating a distinct identification between independent and interdependent contributions from multi-caloric effects. These insights hold significant importance in designing and developing specialized thermodynamic materials, optimizing functional performances and exploring innovative mechanisms.

关键词： adiabatic temperature isothermal entropy Maxwell relations multicaloric effects

Heteroatom anchors Fe-Mn dual-atom catalysts with bi-functional oxygen catalytic activity for low-temperature rechargeable flexible Zn-air batteries

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Journal of Energy Chemistry 2024年第3期90卷 610-620,I0014页

作者： Yuting He Hongtao Li Yi Wang Yufei Jia Yongning Liu Qiang Tan State Key Laboratory for mechanical Behaviour of materials School of Materials Science&EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina

M-N-C(M=Fe,Co,Ni,etc.) catalyst owns high catalytic activity in the oxygen catalytic reaction which is the most likely to replace the Pt-based *** it is still a challenge to further increase the active site *** article constructs the high-efficiency FeMn-N/S-C-1000 catalyst to realize ORR/OER bifunctional catalysis by hetero-atom,bimetal(Fe,Mn) doped simultaneously *** evaluated it as bi-functional electro-catalysts,FeMn-N/S-C-1000 exhibits excellent catalytic activity(E_(1/2)=0.924 V,E_(j=10)=1.617 V) in alkaline media,outperforms conventional Pt/C,RuO_(2) and most non-precious-metal catalysts reported recently,Such outstanding performance is owing to N,S co-coordinated with metal to form multi-types of single atom,dual atom active sites to carry out ***,nitrite poison test provides the proof that the active sites of FeMn-N/S-C are more than that of single-atom catalysts to promote catalytic reactions *** better understand the local structure of Fe and Mn active sites,XAS and DFT were employed to reveal that FeMn-N_5/S-C site plays the key role during ***,the FeMn-N/S-C-1000 based low-temperature rechargeable flexible Zn-air also exhibits superior discharge performance and extraordinary durability at-40℃.This work will provide a new idea to design diatomic catalysts applied in low-temperature rechargeable batteries.

关键词： Fe Mn-N/S-C-1000 ORR OER Rechargeable flexible Zn-air batteries

Effect of oxide inclusions on MnS precipitates and tensile mechanical property of high-strength low-alloy steel

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1210-1220页

作者： Xiao-yong Gao Hong Wei Li-feng Zhang School of mechanical engineering Yanshan UniversityQinhuangdao066004HebeiChina School of materials Science and engineering Yanshan UniversityQinhuangdao066004HebeiChina School of mechanical and materials engineering North China University of TechnologyBeijing100144China

The key role of oxide inclusions on the microstructure and mechanical property of a high-strength low-alloy steel was *** field emission scanning electron microscope equipped with energy-dispersive spectrometry was used to characterize MnS *** inclusions play an important role in the shape control of MnS *** oxides fovored to decrease the size and the aspect ratio of MnS *** less oxide inclusions in the steel,approximately over 16.7%MnS precipitates were with aspect ratio a>5 and pure MnS precipitates accounted for 75.9%in ***,with more oxide inclusions in the steel,only 7.4%MnS precipitates were with a>5 and pure MnS precipitates accounted for 60.1%in *** of MnS by oxide inclusions improved the strength and inhibited the *** oxide inclusions in the steel increased the yield strength and tensile strength of the steel in both longitudinal and transverse directions,and lowered the anisotropy of the mechanical property.

关键词： High-strength low-alloy steel MnS Oxide inclusion mechanical property Anisotropy

Regulating the intrinsic electronic structure of carbon nanofibers with high-spin state Ni for sodium storage with high-power density

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Journal of materials Science & Technology 2024年第4期171卷 16-23页

作者： Zhijia Zhang Gang Xie Yuefang Chen Yanhao Wei Mengmeng Zhang Shulei Chou Yunxiao Wang Yifang Zhang Yong Jiang School of materials Science and engineering Institute of Quantum Materials and DevicesState Key Laboratory of Separation Membrane and Membrane ProcessesTiangong UniversityTianjin 300387China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China Institute for Superconducting and Electronic materials University of WollongongWollongongNSW 2522Australia

Carbon nanofibers(CNFs)with high specific surface area show great potential for sodium storage as a hard carbon ***,CNFs anchored with Ni nanoparticles(CNFs/Ni)were prepared through chemical vapor deposition and impregnation reduction methods,in situ growing on the three-dimensional porous copper current collector(3DP-Cu).The coupling effect of high-spin state Ni nanopar-ticles leads to the increase of defect density and the expansion of lattice spacing of ***,the 3DP-Cu ensures a high loading capacity of CNFs and short ion/electron transport *** an integral binder-free anode,the 3DP-Cu/CNFs/Ni exhibits excellent electrochemical performance,which demon-strates a high specific capacity with 298.5 mAh g^(-1)at 1000 mA g^(-1)after 1500 cycles,and a high power density with 200 mAh g^(-1)over 1000 cycles at 5000 mA g^(-1).Density functional theory calculation re-sults show that the high-spin state Ni regulates the electronic structure of CNFs,which significantly reduces the adsorption energy for Na^(+)(-2.7 Ev)and thus enables high-rate *** regulation of the electronic structure of carbon materials by high-spin state metal provides a new strategy for developing high-power carbonaceous anode materials for sodium-ion batteries.

关键词： Carbon nanofibers Ni nanoparticles High-spin state Sodium-ion batteries Anode materials Density functional theory calculation