Magnesium-lithium hybrid batteries(MLHBs)have gained increasing attention due to their combined advantages of rapid ion insertion/extraction cathode and magnesium metal anode.Herein,Sn S_(2)-SPAN hybrid cathode with s...Magnesium-lithium hybrid batteries(MLHBs)have gained increasing attention due to their combined advantages of rapid ion insertion/extraction cathode and magnesium metal anode.Herein,Sn S_(2)-SPAN hybrid cathode with strong C-Sn bond and rich defects is ingeniously constructed to realize Mg^(2+)/Li^(+)co-intercalation.The physical and chemical double-confinement synergistic engineering of sulfurized polyacrylonitrile can suppress the agglomeration of Sn S_(2)nanoparticles and the volume expansion,simultaneously promote charge transfer and enhance structural stability.The introduced abundant sulfur vacancies provide more active sites for Mg^(2+)/Li^(+)co-intercalation.Meanwhile,the beneficial effects of rich sulfur defects and C-Sn bond on enhanced electrochemical properties are further evidenced by density-functional theory(DFT)calculations.Therefore,compared with pristine SnS_(2),SnS_(2)-SPAN cathode displays high specific capacity(218 m Ah g^(-1)at 0.5A g^(-1)over 700 cycles)and ultra-long cycling life(101 m Ah g^(-1)at 5 A g^(-1)up to 28,000 cycles).And a high energy density of 307 Wh kg^(-1)can be realized by the Sn S_(2)-SPAN//Mg pouch cell.Such elaborate and simple design supplies a reference for the exploitation of advanced cathode materials with excellent electrochemical properties for MLHBs.展开更多
Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosize...Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosized anatase TiO_(2) exposed(001)facet doubles the capacity compared to the micro-sized sample ascribed to the interfacial Mg^(2+)ion storage.First-principles calculations reveal that the diffusion energy barrier of Mg^(2+)on the(001)facet is significantly lower than those in the bulk phase and on(100)facet,and the adsorption energy of Mg^(2+)on the(001)facet is also considerably lower than that on(100)facet,which guarantees superior interfacial Mg^(2+)storage of(001)facet.Moreover,anatase TiO_(2) exposed(001)facet displays a significantly higher capacity of 312.9 mAh g^(−1) in Mg-Li dual-salt electrolyte compared to 234.3 mAh g^(−1) in Li salt electrolyte.The adsorption energies of Mg^(2+)on(001)facet are much lower than the adsorption energies of Li+on(001)facet,implying that the Mg^(2+)ion interfacial storage is more favorable.These results highlight that controlling the crystal facet of the nanocrystals effectively enhances the interfacial storage of multivalent ions.This work offers valuable guidance for the rational design of high-capacity storage systems.展开更多
AZ31 Mg alloy with heterogeneous bimodal grain structure(smaller grain size of 5-20µm and coarser grain size of 100-200µm)was subjected to accumulated extrusion bonding(AEB)at 250℃combined with two-stage ar...AZ31 Mg alloy with heterogeneous bimodal grain structure(smaller grain size of 5-20µm and coarser grain size of 100-200µm)was subjected to accumulated extrusion bonding(AEB)at 250℃combined with two-stage artificial cooling in this work,viz.local water cooling and artificial cooling.The microstructure developed consecutively as a result of discontinuous dynamic recrystallization(DDRX)for the AEBed samples.{10-12}tensile twinning also played an important role for the AEB with local water cooling at the initial extrusion stage in the container.Local water cooling could further reduce the DRXed grain size to~2.1µm comparing that without water cooling.And the grain growth rate was reduced by artificial cooling out of extrusion die.Under the combination of two-stage cooling,the fine DRXed grains at sizing band were almost retained with average grain size of~2.3µm after the sheet out of extrusion die,and the unDRXed grains with high residual dislocation density accumulation were also reserved.The tensile tests results indicated that a good strength-ductility balance with a high ultimate tensile strength(319 MPa vs.412 MPa)and fracture elongation(19.9%vs.30.3%)were obtained.The strength enhancement was mainly owing to the grain refinement and local residual plastic strain reserved by the artificial cooling.The excellent ductility originated from fine DRXed microstructure and ED-tilt double peak texture.展开更多
The negative thermal expansion(NTE) phenomenon is of great significance in fabricating zero thermal expansion(ZTE) materials to avoid thermal shock during heating and cooling. NTE is observed in limited groups of mate...The negative thermal expansion(NTE) phenomenon is of great significance in fabricating zero thermal expansion(ZTE) materials to avoid thermal shock during heating and cooling. NTE is observed in limited groups of materials, e.g., metal cyanides, oxometallates, and metalorganic frameworks, but has not been reported in the family of metal hydrides. Herein, a colossal and continuous negative thermal expansion is firstly developed in the low-temperature phases of LT1-and LT2-Mg_(2)NiH_(4) between 488 K and 733 K from in-situ transmission electron microscope(TEM) video, with the volume contraction reaching 18.7% and 11.3%, respectively. The mechanisms for volume contraction of LT1 and LT2 phases are elucidated from the viewpoints of phase transformation, magnetic transition, and dehydrogenation, which is different from common NTE materials containing flexible polyhedra units in the structure. The linear volume shrinkage of LT2 in the temperature of 488-553 K corresponds to the phase transition of LT2→HT with a thermal expansion coefficient of -799.7 × 10^(-6) K^(-1) revealed by in-situ synchrotron powder X-ray diffraction. The sudden volume contraction in LT1 between 488 and 493 K may be caused by the rapid dehydrogenation of LT1 to Mg_(2)Ni. The revealed phenomenon in single composite material with different structures would be significant for preparing zero thermal expansion materials by tuning the fraction of LT1 and LT2 phases.展开更多
Mg and its alloys show high potential to be applied as implant materials due to their superior properties like biodegradability,bioactivity,biocompatibility,and suitable mechanical behaviors.Nevertheless,the fast and ...Mg and its alloys show high potential to be applied as implant materials due to their superior properties like biodegradability,bioactivity,biocompatibility,and suitable mechanical behaviors.Nevertheless,the fast and uncontrolled degradation of Mg alloys in biological environment severely restricts their wide applications as biomedical materials.In comparison with alloying,surface coatings can not only improve corrosion resistance but also impart other bio-functional properties to achieve diverse clinical requirements.This review analyzes and summarizes the most recent developments in popular coating technologies,including micro-arc oxidation,electrophoretic deposition,chemical conversion,anodic oxidation,layered double hydroxide,and sol-gel coatings.Considering inevitable damages under complex service conditions,smart self-healing coatings are also introduced in each coating technology.The existing issues and future perspectives are finally discussed to facilitate applications of Mg alloys as biomedical materials in the medical industry.展开更多
As one of the lightest engineering materials,magnesium(Mg)alloy possesses excellent mechanical performance,meeting the needs of versatile engineering fields and holding the potential to address cutting-edge issues in ...As one of the lightest engineering materials,magnesium(Mg)alloy possesses excellent mechanical performance,meeting the needs of versatile engineering fields and holding the potential to address cutting-edge issues in aerospace,electronics,biomedicine.The design of superhydrophobic(SHB)surfaces with micro and nanostructures can endow Mg alloys with multiple functionalities,such as self-cleaning,self-healing,antibacterial,and corrosion resistance.Over the past decade,researchers have drawn inspiration from nature to implement biomimetic design principles,resulting in the rapid development of micro/nanostructured SHB surfaces on Mg alloys,which hold great promise for biomedical applications.This review comprehensively introduces the biomimetic design principles of micro/nanostructured SHB surfaces on Mg alloys,discusses the challenges along with advantages and disadvantages of current preparation methods,and explores the future perspectives for preparing these SHB surfaces,providing strategies to enhance their performance in biomedical applications.展开更多
The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg al...The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg alloy systems at 500℃are systematically investigated.The solid solution behavior of a set of two different alloying elements in Mg alloy systems are suggested to be classified into three categories:inclusivity,exclusivity and proportionality.Inclusivity classification indicates that the two alloying elements are inclusive inα-Mg,increasing the joint solubility of both elements.Exclusivity classification suggests that the two alloying elements have a low joint solid solubility inα-Mg,since they prefer to form stable second phases.For the proportionality classification,the solubility curve of the ternary Mg alloy systems is a straight line connecting the solubility points of the two sub-binary systems.The proposed classification theory was validated by key experiments and the calculation of formation energies.The interaction effects between alloying elements and the preference of formation of second phases are the main factors determining the solid solution behavior classifications.Based on the observed solid solution features of multi-component Mg alloys,principles for alloy design of different types of high-performance Mg alloys were proposed in this work.展开更多
Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,...Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,such as micro-arc oxidation(MAO).In this study,we investigated the influence of the Ti-reinforcement phase on coating growth and evolution by subjecting both AZ91 alloy and AZ91/Ti composite to MAO treatment using silicate-based and phosphate-based electrolytes.Results revealed that the Ti-reinforcement phase influenced the MAO process,altering discharge behavior,and leading to a decreased cell voltage.The vigorous discharge of the Ti-reinforcement phase induced the formation of coating discharge channels,concurrently dissolving and oxidizing Ti-reinforcement to produce a composite ceramic coating with TiO2.The MAO coating on the AZ91/Ti composite exhibited a dark blue macromorphology and distinctive local micromorphological anomalies.In silicate electrolyte,a“volcano-like”localized morphology centered on the discharge channel emerged.In contrast,treatment in phosphate-based electrolyte resulted in a coating morphology similar to typical porous ceramic coatings,with visible radial discharge micropores at the reinforcement phase location.Compared to the AZ91 alloy,the coating on the AZ91/Ti composite exhibited lower thickness and higher porosity.MAO treatment reduced the self-corrosion current density of the AZ91/Ti surface by two orders of magnitude.The silicate coating demonstrated better corrosion resistance than the phosphate coating,attributed to its lower porosity.The formation mechanism of MAO coatings on AZ91/Ti composites in phosphate-based and silicate-based electrolytes was proposed.展开更多
Magnesium alloys have gained extensive applications across various industries,including aerospace,transportation,and civil construction,owing to their excellent combinations of high specific strength and stiffness[1]....Magnesium alloys have gained extensive applications across various industries,including aerospace,transportation,and civil construction,owing to their excellent combinations of high specific strength and stiffness[1].However,their lim-ited strength due to the lack of effective strengthening phases has hindered their broader industrial applications[2].Never-theless,it has been challenging to achieve significant strength-ening due to the restricted solubility of alloying elements in magnesium[3].Thus,more and more efforts have been made to explore the concept of secondary phase-reinforced magne-sium alloys[2,4,5],where the secondary phase acts as re-inforcing agents within the magnesium matrix,resembling a composite material.展开更多
Magnesium(Mg)and its alloys have been identified as one of the most promising structural,energy and biomaterials owing to their exceptional combination of properties.These include low density,high specific strength,go...Magnesium(Mg)and its alloys have been identified as one of the most promising structural,energy and biomaterials owing to their exceptional combination of properties.These include low density,high specific strength,good damping,high castability,high capacity of hydrogen storage。展开更多
The widespread application of magnesium(Mg)and Mg alloys is limited by their poor corrosion resistance.Micro-arc oxidation(MAO)is a common surface treatment,but the inherent defects of the MAO coating require post-tre...The widespread application of magnesium(Mg)and Mg alloys is limited by their poor corrosion resistance.Micro-arc oxidation(MAO)is a common surface treatment,but the inherent defects of the MAO coating require post-treatment to ensure good corrosion protection.Therefore,various zeolitic imidazolate framework ZIF-67@Co-M(M=Fe,Al,Ni)layered double hydroxides(LDHs)composite coatings were fabricated on MAO-treated AZ31 Mg alloy to enhance its corrosion resistance.The surface characteristics,coating thickness,corrosion resistance and protection mechanisms of the ZCM(ZIF-67@Co-M LDHs)composite coatings were examined.The findings indicate that the ZCF(ZIF-67@Co-Fe LDHs)composite coating exhibits the lowest corrosion current density(i_(corr)=7.76×10^(-8)A/cm^(2)),superior corrosion resistance,the lowest corrosion rate(HEV=2.46 mL·cm^(-2))and the fastest response speed to corrosion.The synergistic integration of ZIF-67 and LDHs effectively prevents the invasion of corrosive media,enhancing both short-term and long-term corrosion resistance of AZ31 alloys.These composite coatings surpass the limitations of individual materials,providing a promising strategy for durable corrosion protection.展开更多
The low strength of Mg-Li alloys sets a limit to lightweight applications.Introducing crystal defects(twins,dislocations,and SFs)is a distinctive strategy for maintaining good mechanical properties of metallic materia...The low strength of Mg-Li alloys sets a limit to lightweight applications.Introducing crystal defects(twins,dislocations,and SFs)is a distinctive strategy for maintaining good mechanical properties of metallic materials.A lamellar-structured Mg-4Li-3Al-0.4Ca alloy with high performance was prepared by hot extrusion and rotary swaging.The as-swaged alloy exhibits excellent mechanical properties with tensile strength,yield strength,elongation to failure,and specific strength of 391 MPa,312 MPa,14.2%,and 238.4 kN m kg^(-1),respectively.The average grain size of the as-swaged alloy is 160±23 nm,and the microstructure is mainly composed of lamellar structures,twins,ultrafine grains,and nano-grains.The abundant lamellar structures and twins promote the storage of dislocations and SFs,leading to the formation of twin-twin interactions and enhancing strain hardening.The formation of UFG and NG by dynamic recrystallization further improves the yield strength.Shearable second phases play a critical role in enhancing the yield strength and ductility.More importantly,extensive planar dislocation glide and(c+a)dislocations efficiently relax the local stress concentrations,and thus improve the ductility.展开更多
A CaCO_(3)coating with good anticorrosion and adhesion performance was fabricated via ultrasound-assisted chemical conversion on AZ41 magnesium alloy,with a water-bath treated coating as a control.The coating formed o...A CaCO_(3)coating with good anticorrosion and adhesion performance was fabricated via ultrasound-assisted chemical conversion on AZ41 magnesium alloy,with a water-bath treated coating as a control.The coating formed on AZ41 mainly consists of an outer CaCO_(3)layer and an inner(Ca,Mg)CO_(3)layer.Surface characterizations were carried out to obtain the morphology and the chemical composition,mechanical tests were also adopted to assess the hardness and the adhesion of the coating prepared.Afterwards,the long-term corrosion resistance was investigated via electrochemical methods in the chloride-containing Portland cement system.Results show that the ultrasound-assisted coating exhibits higher mechanical properties.In addition,the corrosion resistance of the ultrasound-assisted coating is also higher than that of the bare AZ41 alloy and the water-bath treated coating.This could be due to the formation of a much more compact CaCO_(3)coating on AZ41 Mg alloy,which is mainly benefit from the assistance of the ultrasound.Ultrasound accelerates the nucleation of CaCO_(3)crystals and assists the removal of hydrogen bubbles.Additionally,corrosion mechanism was suggested and discussed for the CaCO_(3)coating.展开更多
Rechargeable magnesium batteries(RMBs)have attracted much attention due to the high theoretical capacity(3833 mAh cm−3)of magnesium metal negative electrode and abundant resources.However,the preparation of ultra-thin...Rechargeable magnesium batteries(RMBs)have attracted much attention due to the high theoretical capacity(3833 mAh cm−3)of magnesium metal negative electrode and abundant resources.However,the preparation of ultra-thin magnesium foils faces the problems of rolling difficulty and high processing cost,while the use of thick magnesium foils leads to low utilization of magnesium and reduces the energy density.To tackle the above problems,we successfully prepared ultra-thin magnesium foils based on electrolytic process and investigated the effect of different substrates.The magnesium foils prepared using Mo substrate have more uniform surface morphology and lower surface roughness,which is attributed to the lower magnesium nucleation overpotential of Mo substrate.Meanwhile,density functional theory calculations show that the adsorption energy of Mo on Mg is more negative,which is conducive to achieving uniform nucleation and deposition of Mg.The Mg deposition on Mo substrate undergoes the characteristic stages of transient nucleation,nucleus accretion,multidirectional heterotopic growth,and columnar crystal stacking,and ultimately the formation of a dense deposited layer.In addition,the prepared ultra-thin Mg foil with Mo substrate can stably cycle for 1000 h at 3 mA cm^(-2) with high utilization of 50% in the symmetric cell.This study develops a facile method for the preparation of ultra-thin Mg foils,which opens up a new path for developing high-performance ultra-thin negative electrodes for RMBs.展开更多
Aging precipitation can effectively enhance the strength of Mg–RE alloys,but it is usually accompanied by a significant decrease in ductility,thus the strength–ductility trade-off is a longstanding challenge.In this...Aging precipitation can effectively enhance the strength of Mg–RE alloys,but it is usually accompanied by a significant decrease in ductility,thus the strength–ductility trade-off is a longstanding challenge.In this study,we report a new strategy that coupled pre-deformation(pre-tension along the extrusion direction(ED)followed by pre-compression along transverse direction(TD))with artificial aging to achieve an exceptional strength–ductility synergy in the WE54 alloy at RT.We analyzed the microstructure,deformation modes and mechanical properties of four samples:T6(artificial aging),PT-T6(pre-tension+artificial aging),PC-T6(pre-compression+artificial aging),and PTC-T6(coupled pre-deformation+artificial aging).The PTC-T6 sample exhibited the superior strength–plasticity synergy,showing a strength increase of 111.9 MPa over the T6 sample and only a slight decrease in elongation to fracture.The PTC-T6 sample features finer and denser precipitates,along with a higher dislocation density,particularly a significant presence of<c+a>dislocations.This microstructural configuration enhances strength and facilitates the activation of pyramidal slip,which is the primary factor underlying its superior strength–ductility synergy.展开更多
The paper study the interfacial mechanical properties and structural evolution mechanisms in 6061/AZ31B/6061 composite plates with and without Ni foil interlayers.For Ni-free interfaces,a continuous diffusion layer(3....The paper study the interfacial mechanical properties and structural evolution mechanisms in 6061/AZ31B/6061 composite plates with and without Ni foil interlayers.For Ni-free interfaces,a continuous diffusion layer(3.5-4.0μm)forms,dominated by brittle columnar Al_(12)Mg_(17) intermetallic compounds(IMCs,0.27-0.35μm thick),which act as preferential crack initiation sites.In contrast,Ni foil implantation induces interfacial restructuring during hot rolling:Constrained deformation fragments the Ni foil into grid-like segments with"olive"-shaped crosssections,embedded into Mg/Al matrices.These fragments(56% areal coverage)coexist with dispersed multiphase IMCs(Mg_(2)Ni,Al_(3)Ni,Mg_(3)AlNi,Al_(12)Mg_(17);10-20 nm grains)at fragment edges,forming a hybrid interface of"willow-leaf"Al_(12)Mg_(17) islands and nanoscale Mg_(2)Ni/Al_(3)Ni layers(15-25 nm).Hall-Petch analysis reveals the multiphase IMC interface exhibits 3.6×higher"kd^(-1/2)"strengthening contribution than single-phase Al_(12)Mg_(17) systems,attributed to grain refinement(20 nm vs.260 nm average grain size).Synergistic effects of mechanical interlocking,adhesion hierarchy(Ni-Al>Ni-Mg>Al-Mg),and nanoscale reinforcement collectively enhance peel strength by 78%without compromising bulk tensile properties.展开更多
Magnesium ion batteries(MIBs)are a promising alternative to lithium-ion batteries,which suffer from the short cycling life and sluggish Mg^(2+)diffusion kinetics of cathodes.Nano morphologies are used to shorten Mg^(2...Magnesium ion batteries(MIBs)are a promising alternative to lithium-ion batteries,which suffer from the short cycling life and sluggish Mg^(2+)diffusion kinetics of cathodes.Nano morphologies are used to shorten Mg^(2+)diffusion path for diffusion kinetics acceleration,but the cycling life is still unsatisfactory.Herein,the anisotropy of layered V_(3)O_(7)·1.9H_(2)O nanobelts is utilized to stabilize their structure during discharging/charging.The V_(3)O_(7)·1.9H_(2)O nanobelts grow along the preponderant migration direction of Mg^(2+),and the resulted axial migration of Mg^(2+)enables the stress caused by Mg^(2+)insertion to be decentralized in large zone,thus improving the cycling stability of V_(3)O_(7)·1.9H_(2)O nanobelts.The inserted Mg^(2+)cations bond with O atoms in adjacent V3O8 layers of V_(3)O_(7)·1.9H_(2)O,further stablizing the layered structure.Meanwhile,the axial migration of Mg^(2+)significantly reduces the charge transfer resistance at electrode/electrolyte interface,which accelerates the Mg^(2+)diffusion kinetics.Thus,the symmetric RMB assembled from V_(3)O_(7)·1.9H_(2)O nanobelts exhibits an ultralong cycling life of 11,000 cycles at 4 A g^(-1),alongside a high specific capacity of 137 mAh g^(-1)at 0.05 A g^(-1).According to our knowledge,this ultralong cycling life surpasses those of reported full RMBs.This strategy provides insight into the design of cathode materials with improved cycling lives.展开更多
High purity magnesium is not only an important basic raw material for semiconductor and electronics industries,but also a promising new generation of electrochemical energy storage materials and biomedical materials.I...High purity magnesium is not only an important basic raw material for semiconductor and electronics industries,but also a promising new generation of electrochemical energy storage materials and biomedical materials.Impurities in high-purity magnesium affect material properties,which has become the most critical factor restricting its application.However,accurate analysis of multiple ultra-trace impurity elements in high-purity magnesium is extremely challenging.In this paper,based on the synergistic effect of N_(2)O/H_(2) reaction gas mixture to eliminate spectral interference of inductively coupled plasma tandem mass spectrometry(ICP-MS/MS),a new strategy for the quantification of 45 ultra-trace impurity elements in high-purity magnesium was proposed.The results indicated that the limits of detection(LOD)were in the range of 0.02–18.5 ng L^(−1);the LODs of the challenging non-metallic elements Si and S were 18.5 and 12.2 ng L^(−1),respectively;and the LODs of all the other analytes were less than 10 ng L^(−1).Even under hot plasma conditions,LODs of alkali metal elements were also less than 5 ng L^(−1).The spike recovery of each analyte was 93.6%–107%,and the relative standard deviation(RSD)was 3.2%–6.9%,respectively.At a 95%level of confidence,no significant differences were found between the results obtained under the optimal conditions for the analyte with the developed method and the measurement results of SF-ICP-MS.The developed method indicated low LOD,high sample throughput,and complete interference elimination,demonstrating a new avenue for the rapid determination of ultra-trace elements in high-purity magnesium.展开更多
While early transition metal-based materials,such as MXene,has emerged as an efficient catalyst for the Mg-based hydrogen storage materials,their strong interaction with hydrogen resulted in the high hydrogen diffusio...While early transition metal-based materials,such as MXene,has emerged as an efficient catalyst for the Mg-based hydrogen storage materials,their strong interaction with hydrogen resulted in the high hydrogen diffusion barrier,hindering further improvement of catalytic activity.A MXene is characterized by rich anionic groups on its surface,significantly affecting electronic and catalytic functionalities.Using Nb_(2)CT_(x)as an example,we herein illustrate the critical role of anionic T_(x)defects on controlling hydrogen dissociation and diffusion processes in Mg-based hydrogen storage materials.The hydrogen desorption properties of MgH_(2)can be significantly enhanced by utilizing T_(x)controllable Nb_(2)CT_(x),and it can release 3.57 wt.%hydrogen within 10 min under 240℃with the reduced dehydrogenation activation barrier.It also realized stable de/hydrogenation reactions for at least 50 cycles.DFT studies combined with kinetic analysis revealed that the catalyst‒hydrogen interaction could be systematically controlled by optimizing surface T_(x)defect density,accelerating the hydrogen dissociation and diffusion processes at the same time.These results demonstrate that the T_(x)defects serve as the effective catalytically active centers of Nb_(2)CT_(x),offering a flexible catalyst design guideline.展开更多
Magnesium(Mg)alloys offer significant potential for conductive applications,thanks to their distinctive attributes,including high specific strength,excellent electrical conductivity(EC),low density,electromagnetic int...Magnesium(Mg)alloys offer significant potential for conductive applications,thanks to their distinctive attributes,including high specific strength,excellent electrical conductivity(EC),low density,electromagnetic interference shielding effectiveness(EMI SE),and recyclability.However,a major challenge in Mg alloy research is balancing high strength with good EC,as strengthening these alloys often compromises their EC.This paper offers an in-depth analysis of the mechanisms,strategies,and applications aimed at improving the EC of Mg alloys.A bibliometric study is performed to uncover the main research trends and emerging hotspots within the field.The review then examines various strategies to improve EC focusing on factors such as solute elements,second phases,grain boundaries,textures,and vacancies.By carefully controlling alloy composition and optimizing heat treatment processes,significant advancements have been achieved by researchers in developing Mg alloys that possess both high strength and high EC,especially in Mg-Al,Mg-Zn,Mg-RE alloy systems and composites.Finally,the paper outlines future research directions,stressing the importance of further exploration into alloying element selection,heat treatment optimization,and other advanced strategies.These efforts are crucial for overcoming current challenges and expanding the application of Mg alloys in EC fields.展开更多
基金financially supported by the National Key R&D Program of China(No.2023YFB3809500)National Natural Science Foundation of China(Grant No.51931006,52272240 and U22A20118)+2 种基金the Fundamental Research Funds for the Central Universities of China(Xiamen University:No.20720220074)Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(HRTP-[2022]-22)the“Double-First Class”Foundation of Materials Intelligent Manufacturing Discipline of Xiamen University。
文摘Magnesium-lithium hybrid batteries(MLHBs)have gained increasing attention due to their combined advantages of rapid ion insertion/extraction cathode and magnesium metal anode.Herein,Sn S_(2)-SPAN hybrid cathode with strong C-Sn bond and rich defects is ingeniously constructed to realize Mg^(2+)/Li^(+)co-intercalation.The physical and chemical double-confinement synergistic engineering of sulfurized polyacrylonitrile can suppress the agglomeration of Sn S_(2)nanoparticles and the volume expansion,simultaneously promote charge transfer and enhance structural stability.The introduced abundant sulfur vacancies provide more active sites for Mg^(2+)/Li^(+)co-intercalation.Meanwhile,the beneficial effects of rich sulfur defects and C-Sn bond on enhanced electrochemical properties are further evidenced by density-functional theory(DFT)calculations.Therefore,compared with pristine SnS_(2),SnS_(2)-SPAN cathode displays high specific capacity(218 m Ah g^(-1)at 0.5A g^(-1)over 700 cycles)and ultra-long cycling life(101 m Ah g^(-1)at 5 A g^(-1)up to 28,000 cycles).And a high energy density of 307 Wh kg^(-1)can be realized by the Sn S_(2)-SPAN//Mg pouch cell.Such elaborate and simple design supplies a reference for the exploitation of advanced cathode materials with excellent electrochemical properties for MLHBs.
基金supported by the National Key R&D Program of China(No.2023YFB3809500)the Fundamental Research Funds for the Central Universities(No.2024CDJXY003)+1 种基金the Venture&Innovation Support Program for Chongqing Overseas Returnees(cx2023087)The Chongqing Technology Innovation and Application Development Project(No.2024TIAD-KPX0003).
文摘Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosized anatase TiO_(2) exposed(001)facet doubles the capacity compared to the micro-sized sample ascribed to the interfacial Mg^(2+)ion storage.First-principles calculations reveal that the diffusion energy barrier of Mg^(2+)on the(001)facet is significantly lower than those in the bulk phase and on(100)facet,and the adsorption energy of Mg^(2+)on the(001)facet is also considerably lower than that on(100)facet,which guarantees superior interfacial Mg^(2+)storage of(001)facet.Moreover,anatase TiO_(2) exposed(001)facet displays a significantly higher capacity of 312.9 mAh g^(−1) in Mg-Li dual-salt electrolyte compared to 234.3 mAh g^(−1) in Li salt electrolyte.The adsorption energies of Mg^(2+)on(001)facet are much lower than the adsorption energies of Li+on(001)facet,implying that the Mg^(2+)ion interfacial storage is more favorable.These results highlight that controlling the crystal facet of the nanocrystals effectively enhances the interfacial storage of multivalent ions.This work offers valuable guidance for the rational design of high-capacity storage systems.
基金The authors are grateful for the National Natural Science Foundation of China(No.51905366 and U1810122)Yantai high-end talent introduction"Double Hundred Plan"(2021)Key Research and Development Program of Shanxi Province(201903D421076).
文摘AZ31 Mg alloy with heterogeneous bimodal grain structure(smaller grain size of 5-20µm and coarser grain size of 100-200µm)was subjected to accumulated extrusion bonding(AEB)at 250℃combined with two-stage artificial cooling in this work,viz.local water cooling and artificial cooling.The microstructure developed consecutively as a result of discontinuous dynamic recrystallization(DDRX)for the AEBed samples.{10-12}tensile twinning also played an important role for the AEB with local water cooling at the initial extrusion stage in the container.Local water cooling could further reduce the DRXed grain size to~2.1µm comparing that without water cooling.And the grain growth rate was reduced by artificial cooling out of extrusion die.Under the combination of two-stage cooling,the fine DRXed grains at sizing band were almost retained with average grain size of~2.3µm after the sheet out of extrusion die,and the unDRXed grains with high residual dislocation density accumulation were also reserved.The tensile tests results indicated that a good strength-ductility balance with a high ultimate tensile strength(319 MPa vs.412 MPa)and fracture elongation(19.9%vs.30.3%)were obtained.The strength enhancement was mainly owing to the grain refinement and local residual plastic strain reserved by the artificial cooling.The excellent ductility originated from fine DRXed microstructure and ED-tilt double peak texture.
基金supported by the National Key Research and Development Program of China (2021YFB3701001)the National Natural Science Foundation of China (51871143)+1 种基金Shanghai Engineering Research Center for Metal Parts Green Remanufacture (No.19DZ2252900) from Shanghai Engineering Research Center Construction ProjectShanghai Rising-Star Program (21QA1403200)。
文摘The negative thermal expansion(NTE) phenomenon is of great significance in fabricating zero thermal expansion(ZTE) materials to avoid thermal shock during heating and cooling. NTE is observed in limited groups of materials, e.g., metal cyanides, oxometallates, and metalorganic frameworks, but has not been reported in the family of metal hydrides. Herein, a colossal and continuous negative thermal expansion is firstly developed in the low-temperature phases of LT1-and LT2-Mg_(2)NiH_(4) between 488 K and 733 K from in-situ transmission electron microscope(TEM) video, with the volume contraction reaching 18.7% and 11.3%, respectively. The mechanisms for volume contraction of LT1 and LT2 phases are elucidated from the viewpoints of phase transformation, magnetic transition, and dehydrogenation, which is different from common NTE materials containing flexible polyhedra units in the structure. The linear volume shrinkage of LT2 in the temperature of 488-553 K corresponds to the phase transition of LT2→HT with a thermal expansion coefficient of -799.7 × 10^(-6) K^(-1) revealed by in-situ synchrotron powder X-ray diffraction. The sudden volume contraction in LT1 between 488 and 493 K may be caused by the rapid dehydrogenation of LT1 to Mg_(2)Ni. The revealed phenomenon in single composite material with different structures would be significant for preparing zero thermal expansion materials by tuning the fraction of LT1 and LT2 phases.
基金supported by the Chongqing Natural Science Foundation(No.CSTB2023NSCQ-MSX0512)Municipal Human Resources and Social Security Bureau(No.cx2022098)China Postdoctoral Science Foundation(Nos.2022T150767 and 2021M693708).
文摘Mg and its alloys show high potential to be applied as implant materials due to their superior properties like biodegradability,bioactivity,biocompatibility,and suitable mechanical behaviors.Nevertheless,the fast and uncontrolled degradation of Mg alloys in biological environment severely restricts their wide applications as biomedical materials.In comparison with alloying,surface coatings can not only improve corrosion resistance but also impart other bio-functional properties to achieve diverse clinical requirements.This review analyzes and summarizes the most recent developments in popular coating technologies,including micro-arc oxidation,electrophoretic deposition,chemical conversion,anodic oxidation,layered double hydroxide,and sol-gel coatings.Considering inevitable damages under complex service conditions,smart self-healing coatings are also introduced in each coating technology.The existing issues and future perspectives are finally discussed to facilitate applications of Mg alloys as biomedical materials in the medical industry.
基金supported by the National Natural Science Found for Distinguished Young Scholars(52225101)the Fundamental Research Funds for the Central Universities(WUT:104972024RSCbs0018 and 2023CDJYXTD-002)+1 种基金the Natural Science Foundation of Chongqing(CSTB2023NSCQ-MSX0527)the Chongqing Academician Special Fund(2022YSZXJCX0014CSTB).
文摘As one of the lightest engineering materials,magnesium(Mg)alloy possesses excellent mechanical performance,meeting the needs of versatile engineering fields and holding the potential to address cutting-edge issues in aerospace,electronics,biomedicine.The design of superhydrophobic(SHB)surfaces with micro and nanostructures can endow Mg alloys with multiple functionalities,such as self-cleaning,self-healing,antibacterial,and corrosion resistance.Over the past decade,researchers have drawn inspiration from nature to implement biomimetic design principles,resulting in the rapid development of micro/nanostructured SHB surfaces on Mg alloys,which hold great promise for biomedical applications.This review comprehensively introduces the biomimetic design principles of micro/nanostructured SHB surfaces on Mg alloys,discusses the challenges along with advantages and disadvantages of current preparation methods,and explores the future perspectives for preparing these SHB surfaces,providing strategies to enhance their performance in biomedical applications.
基金financially supported by National Natural Science Foundation of China(grant numbers:52171100,U20A20234)National Key R&D Program of China(grant number:2021YFB3701100)。
文摘The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg alloy systems at 500℃are systematically investigated.The solid solution behavior of a set of two different alloying elements in Mg alloy systems are suggested to be classified into three categories:inclusivity,exclusivity and proportionality.Inclusivity classification indicates that the two alloying elements are inclusive inα-Mg,increasing the joint solubility of both elements.Exclusivity classification suggests that the two alloying elements have a low joint solid solubility inα-Mg,since they prefer to form stable second phases.For the proportionality classification,the solubility curve of the ternary Mg alloy systems is a straight line connecting the solubility points of the two sub-binary systems.The proposed classification theory was validated by key experiments and the calculation of formation energies.The interaction effects between alloying elements and the preference of formation of second phases are the main factors determining the solid solution behavior classifications.Based on the observed solid solution features of multi-component Mg alloys,principles for alloy design of different types of high-performance Mg alloys were proposed in this work.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(Grant No.2020B0301030006).
文摘Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,such as micro-arc oxidation(MAO).In this study,we investigated the influence of the Ti-reinforcement phase on coating growth and evolution by subjecting both AZ91 alloy and AZ91/Ti composite to MAO treatment using silicate-based and phosphate-based electrolytes.Results revealed that the Ti-reinforcement phase influenced the MAO process,altering discharge behavior,and leading to a decreased cell voltage.The vigorous discharge of the Ti-reinforcement phase induced the formation of coating discharge channels,concurrently dissolving and oxidizing Ti-reinforcement to produce a composite ceramic coating with TiO2.The MAO coating on the AZ91/Ti composite exhibited a dark blue macromorphology and distinctive local micromorphological anomalies.In silicate electrolyte,a“volcano-like”localized morphology centered on the discharge channel emerged.In contrast,treatment in phosphate-based electrolyte resulted in a coating morphology similar to typical porous ceramic coatings,with visible radial discharge micropores at the reinforcement phase location.Compared to the AZ91 alloy,the coating on the AZ91/Ti composite exhibited lower thickness and higher porosity.MAO treatment reduced the self-corrosion current density of the AZ91/Ti surface by two orders of magnitude.The silicate coating demonstrated better corrosion resistance than the phosphate coating,attributed to its lower porosity.The formation mechanism of MAO coatings on AZ91/Ti composites in phosphate-based and silicate-based electrolytes was proposed.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030006)the Guangdong Basic and Applied Basic Research Foundation[Grant No.2021B1515120071]+1 种基金R.Shi would like to thank the financial support from the open research fund of Songshan Lake Materials Laboratory(2021SLABFK06)start-up funding from Harbin Institute of Technology(Shenzhen).
文摘Magnesium alloys have gained extensive applications across various industries,including aerospace,transportation,and civil construction,owing to their excellent combinations of high specific strength and stiffness[1].However,their lim-ited strength due to the lack of effective strengthening phases has hindered their broader industrial applications[2].Never-theless,it has been challenging to achieve significant strength-ening due to the restricted solubility of alloying elements in magnesium[3].Thus,more and more efforts have been made to explore the concept of secondary phase-reinforced magne-sium alloys[2,4,5],where the secondary phase acts as re-inforcing agents within the magnesium matrix,resembling a composite material.
文摘Magnesium(Mg)and its alloys have been identified as one of the most promising structural,energy and biomaterials owing to their exceptional combination of properties.These include low density,high specific strength,good damping,high castability,high capacity of hydrogen storage。
基金supported by the National Natural Science Foundation of China(No.52171101)the Fundamental Research Funds for the Central Universities(No.2024IAIS-QN009)the National Key R&D Program of China(No.2021YFB3701100).
文摘The widespread application of magnesium(Mg)and Mg alloys is limited by their poor corrosion resistance.Micro-arc oxidation(MAO)is a common surface treatment,but the inherent defects of the MAO coating require post-treatment to ensure good corrosion protection.Therefore,various zeolitic imidazolate framework ZIF-67@Co-M(M=Fe,Al,Ni)layered double hydroxides(LDHs)composite coatings were fabricated on MAO-treated AZ31 Mg alloy to enhance its corrosion resistance.The surface characteristics,coating thickness,corrosion resistance and protection mechanisms of the ZCM(ZIF-67@Co-M LDHs)composite coatings were examined.The findings indicate that the ZCF(ZIF-67@Co-Fe LDHs)composite coating exhibits the lowest corrosion current density(i_(corr)=7.76×10^(-8)A/cm^(2)),superior corrosion resistance,the lowest corrosion rate(HEV=2.46 mL·cm^(-2))and the fastest response speed to corrosion.The synergistic integration of ZIF-67 and LDHs effectively prevents the invasion of corrosive media,enhancing both short-term and long-term corrosion resistance of AZ31 alloys.These composite coatings surpass the limitations of individual materials,providing a promising strategy for durable corrosion protection.
基金supported by the National Natural Science Foundation of China(Nos.52371093 and 52171104)the National Key Research and Development Program of China(No.2021YFB3701100)the Chongqing Research Program of Basic Research and Frontier Technology,China(Nos.CSTB2023NSCQ-BSX0036 and cstc2021ycjh-bgzxm0086).
文摘The low strength of Mg-Li alloys sets a limit to lightweight applications.Introducing crystal defects(twins,dislocations,and SFs)is a distinctive strategy for maintaining good mechanical properties of metallic materials.A lamellar-structured Mg-4Li-3Al-0.4Ca alloy with high performance was prepared by hot extrusion and rotary swaging.The as-swaged alloy exhibits excellent mechanical properties with tensile strength,yield strength,elongation to failure,and specific strength of 391 MPa,312 MPa,14.2%,and 238.4 kN m kg^(-1),respectively.The average grain size of the as-swaged alloy is 160±23 nm,and the microstructure is mainly composed of lamellar structures,twins,ultrafine grains,and nano-grains.The abundant lamellar structures and twins promote the storage of dislocations and SFs,leading to the formation of twin-twin interactions and enhancing strain hardening.The formation of UFG and NG by dynamic recrystallization further improves the yield strength.Shearable second phases play a critical role in enhancing the yield strength and ductility.More importantly,extensive planar dislocation glide and(c+a)dislocations efficiently relax the local stress concentrations,and thus improve the ductility.
基金the National Key Research and Development Program of China(Grant No.2021YFB3701100)the Natural Science Foundation Commission of China(Grant Nos.U20A20234and 51874062)+1 种基金Chongqing Foundation and Advanced Research Project(Grant No.cstc2019jcyj-zdxmX 0010)the Science and Technology Major Project of Shanxi Province(Grant No.20191102008)。
文摘A CaCO_(3)coating with good anticorrosion and adhesion performance was fabricated via ultrasound-assisted chemical conversion on AZ41 magnesium alloy,with a water-bath treated coating as a control.The coating formed on AZ41 mainly consists of an outer CaCO_(3)layer and an inner(Ca,Mg)CO_(3)layer.Surface characterizations were carried out to obtain the morphology and the chemical composition,mechanical tests were also adopted to assess the hardness and the adhesion of the coating prepared.Afterwards,the long-term corrosion resistance was investigated via electrochemical methods in the chloride-containing Portland cement system.Results show that the ultrasound-assisted coating exhibits higher mechanical properties.In addition,the corrosion resistance of the ultrasound-assisted coating is also higher than that of the bare AZ41 alloy and the water-bath treated coating.This could be due to the formation of a much more compact CaCO_(3)coating on AZ41 Mg alloy,which is mainly benefit from the assistance of the ultrasound.Ultrasound accelerates the nucleation of CaCO_(3)crystals and assists the removal of hydrogen bubbles.Additionally,corrosion mechanism was suggested and discussed for the CaCO_(3)coating.
基金supported by the National Natural Science Foundation of China(No.U2037601)the National Key Research and Development Program(No.2023YFB3809500)the Chongqing Technology Innovation and Application Development Project(No.CSTB2022TIAD-KPX0028).
文摘Rechargeable magnesium batteries(RMBs)have attracted much attention due to the high theoretical capacity(3833 mAh cm−3)of magnesium metal negative electrode and abundant resources.However,the preparation of ultra-thin magnesium foils faces the problems of rolling difficulty and high processing cost,while the use of thick magnesium foils leads to low utilization of magnesium and reduces the energy density.To tackle the above problems,we successfully prepared ultra-thin magnesium foils based on electrolytic process and investigated the effect of different substrates.The magnesium foils prepared using Mo substrate have more uniform surface morphology and lower surface roughness,which is attributed to the lower magnesium nucleation overpotential of Mo substrate.Meanwhile,density functional theory calculations show that the adsorption energy of Mo on Mg is more negative,which is conducive to achieving uniform nucleation and deposition of Mg.The Mg deposition on Mo substrate undergoes the characteristic stages of transient nucleation,nucleus accretion,multidirectional heterotopic growth,and columnar crystal stacking,and ultimately the formation of a dense deposited layer.In addition,the prepared ultra-thin Mg foil with Mo substrate can stably cycle for 1000 h at 3 mA cm^(-2) with high utilization of 50% in the symmetric cell.This study develops a facile method for the preparation of ultra-thin Mg foils,which opens up a new path for developing high-performance ultra-thin negative electrodes for RMBs.
基金financially supported by the National Key Research and Development Program of China(Nos.2021YFB3701000 and 2022YFB3709304)the National Natural Science Foundation of China(Nos.51575068 and 51501023)+2 种基金the Chongqing Natural Science Foundation(No.cstc2021jcyj-msxmX0699)the Venture and Innovation Support Program for Chongqing Overseas Returnees(No.cx2023090)the“111”Project by the Ministry of Education(No.B16007),the Sichuan Science and Technology Program(No.2024NSFSC0193).
文摘Aging precipitation can effectively enhance the strength of Mg–RE alloys,but it is usually accompanied by a significant decrease in ductility,thus the strength–ductility trade-off is a longstanding challenge.In this study,we report a new strategy that coupled pre-deformation(pre-tension along the extrusion direction(ED)followed by pre-compression along transverse direction(TD))with artificial aging to achieve an exceptional strength–ductility synergy in the WE54 alloy at RT.We analyzed the microstructure,deformation modes and mechanical properties of four samples:T6(artificial aging),PT-T6(pre-tension+artificial aging),PC-T6(pre-compression+artificial aging),and PTC-T6(coupled pre-deformation+artificial aging).The PTC-T6 sample exhibited the superior strength–plasticity synergy,showing a strength increase of 111.9 MPa over the T6 sample and only a slight decrease in elongation to fracture.The PTC-T6 sample features finer and denser precipitates,along with a higher dislocation density,particularly a significant presence of<c+a>dislocations.This microstructural configuration enhances strength and facilitates the activation of pyramidal slip,which is the primary factor underlying its superior strength–ductility synergy.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(2020B0301030006)Key Project of Chongqing Technology Innovation and Application Development Special Project(CSTB2023TIADKPX0016,CSTB2022TIAD-KPX0027)+1 种基金National Natural Science Foundation of China(51971183)the Science and Technology Program of Xinjiang Production and Construction Corps(2024AB056).
文摘The paper study the interfacial mechanical properties and structural evolution mechanisms in 6061/AZ31B/6061 composite plates with and without Ni foil interlayers.For Ni-free interfaces,a continuous diffusion layer(3.5-4.0μm)forms,dominated by brittle columnar Al_(12)Mg_(17) intermetallic compounds(IMCs,0.27-0.35μm thick),which act as preferential crack initiation sites.In contrast,Ni foil implantation induces interfacial restructuring during hot rolling:Constrained deformation fragments the Ni foil into grid-like segments with"olive"-shaped crosssections,embedded into Mg/Al matrices.These fragments(56% areal coverage)coexist with dispersed multiphase IMCs(Mg_(2)Ni,Al_(3)Ni,Mg_(3)AlNi,Al_(12)Mg_(17);10-20 nm grains)at fragment edges,forming a hybrid interface of"willow-leaf"Al_(12)Mg_(17) islands and nanoscale Mg_(2)Ni/Al_(3)Ni layers(15-25 nm).Hall-Petch analysis reveals the multiphase IMC interface exhibits 3.6×higher"kd^(-1/2)"strengthening contribution than single-phase Al_(12)Mg_(17) systems,attributed to grain refinement(20 nm vs.260 nm average grain size).Synergistic effects of mechanical interlocking,adhesion hierarchy(Ni-Al>Ni-Mg>Al-Mg),and nanoscale reinforcement collectively enhance peel strength by 78%without compromising bulk tensile properties.
基金supported by the National Natural Science Foundation of China(52222407).
文摘Magnesium ion batteries(MIBs)are a promising alternative to lithium-ion batteries,which suffer from the short cycling life and sluggish Mg^(2+)diffusion kinetics of cathodes.Nano morphologies are used to shorten Mg^(2+)diffusion path for diffusion kinetics acceleration,but the cycling life is still unsatisfactory.Herein,the anisotropy of layered V_(3)O_(7)·1.9H_(2)O nanobelts is utilized to stabilize their structure during discharging/charging.The V_(3)O_(7)·1.9H_(2)O nanobelts grow along the preponderant migration direction of Mg^(2+),and the resulted axial migration of Mg^(2+)enables the stress caused by Mg^(2+)insertion to be decentralized in large zone,thus improving the cycling stability of V_(3)O_(7)·1.9H_(2)O nanobelts.The inserted Mg^(2+)cations bond with O atoms in adjacent V3O8 layers of V_(3)O_(7)·1.9H_(2)O,further stablizing the layered structure.Meanwhile,the axial migration of Mg^(2+)significantly reduces the charge transfer resistance at electrode/electrolyte interface,which accelerates the Mg^(2+)diffusion kinetics.Thus,the symmetric RMB assembled from V_(3)O_(7)·1.9H_(2)O nanobelts exhibits an ultralong cycling life of 11,000 cycles at 4 A g^(-1),alongside a high specific capacity of 137 mAh g^(-1)at 0.05 A g^(-1).According to our knowledge,this ultralong cycling life surpasses those of reported full RMBs.This strategy provides insight into the design of cathode materials with improved cycling lives.
基金supported by the Natural Science Foundation of China(52171103 and 21975289).
文摘High purity magnesium is not only an important basic raw material for semiconductor and electronics industries,but also a promising new generation of electrochemical energy storage materials and biomedical materials.Impurities in high-purity magnesium affect material properties,which has become the most critical factor restricting its application.However,accurate analysis of multiple ultra-trace impurity elements in high-purity magnesium is extremely challenging.In this paper,based on the synergistic effect of N_(2)O/H_(2) reaction gas mixture to eliminate spectral interference of inductively coupled plasma tandem mass spectrometry(ICP-MS/MS),a new strategy for the quantification of 45 ultra-trace impurity elements in high-purity magnesium was proposed.The results indicated that the limits of detection(LOD)were in the range of 0.02–18.5 ng L^(−1);the LODs of the challenging non-metallic elements Si and S were 18.5 and 12.2 ng L^(−1),respectively;and the LODs of all the other analytes were less than 10 ng L^(−1).Even under hot plasma conditions,LODs of alkali metal elements were also less than 5 ng L^(−1).The spike recovery of each analyte was 93.6%–107%,and the relative standard deviation(RSD)was 3.2%–6.9%,respectively.At a 95%level of confidence,no significant differences were found between the results obtained under the optimal conditions for the analyte with the developed method and the measurement results of SF-ICP-MS.The developed method indicated low LOD,high sample throughput,and complete interference elimination,demonstrating a new avenue for the rapid determination of ultra-trace elements in high-purity magnesium.
基金supported by Liuchuang Program of Chongqing Municipality(cx2022038)the Fundamental Research Funds for the Central Universities(2022CDJQY-013)the Graduate Research and Innovation Foundation of Chongqing,China(CYB22005).
文摘While early transition metal-based materials,such as MXene,has emerged as an efficient catalyst for the Mg-based hydrogen storage materials,their strong interaction with hydrogen resulted in the high hydrogen diffusion barrier,hindering further improvement of catalytic activity.A MXene is characterized by rich anionic groups on its surface,significantly affecting electronic and catalytic functionalities.Using Nb_(2)CT_(x)as an example,we herein illustrate the critical role of anionic T_(x)defects on controlling hydrogen dissociation and diffusion processes in Mg-based hydrogen storage materials.The hydrogen desorption properties of MgH_(2)can be significantly enhanced by utilizing T_(x)controllable Nb_(2)CT_(x),and it can release 3.57 wt.%hydrogen within 10 min under 240℃with the reduced dehydrogenation activation barrier.It also realized stable de/hydrogenation reactions for at least 50 cycles.DFT studies combined with kinetic analysis revealed that the catalyst‒hydrogen interaction could be systematically controlled by optimizing surface T_(x)defect density,accelerating the hydrogen dissociation and diffusion processes at the same time.These results demonstrate that the T_(x)defects serve as the effective catalytically active centers of Nb_(2)CT_(x),offering a flexible catalyst design guideline.
基金supported by the National Natural Science Foundation of China(52225101)the Jinhua Science and Technology Program of China(2024A221787)+1 种基金the Sichuan Science and Technology Program of China(2025ZNSFSC0388)the Chongqing Special Project for Science and Technology Innovation of China(CSTB2023YSZX-JCX0006).
文摘Magnesium(Mg)alloys offer significant potential for conductive applications,thanks to their distinctive attributes,including high specific strength,excellent electrical conductivity(EC),low density,electromagnetic interference shielding effectiveness(EMI SE),and recyclability.However,a major challenge in Mg alloy research is balancing high strength with good EC,as strengthening these alloys often compromises their EC.This paper offers an in-depth analysis of the mechanisms,strategies,and applications aimed at improving the EC of Mg alloys.A bibliometric study is performed to uncover the main research trends and emerging hotspots within the field.The review then examines various strategies to improve EC focusing on factors such as solute elements,second phases,grain boundaries,textures,and vacancies.By carefully controlling alloy composition and optimizing heat treatment processes,significant advancements have been achieved by researchers in developing Mg alloys that possess both high strength and high EC,especially in Mg-Al,Mg-Zn,Mg-RE alloy systems and composites.Finally,the paper outlines future research directions,stressing the importance of further exploration into alloying element selection,heat treatment optimization,and other advanced strategies.These efforts are crucial for overcoming current challenges and expanding the application of Mg alloys in EC fields.
