Mg-based materials are one of the most promising hydrogen storage candidates due to their high hydrogen storage capacity,environmental benignity,and high Clarke number characteristics.However,the limited thermodynamic...Mg-based materials are one of the most promising hydrogen storage candidates due to their high hydrogen storage capacity,environmental benignity,and high Clarke number characteristics.However,the limited thermodynamics and kinetic properties pose major challenges for their engineering applications.Herein,we review the recent progress in improving their thermodynamics and kinetics,with an emphasis on the models and the influence of various parameters in the calculated models.Subsequently,the impact of alloying,composite,and nanocrystallization on both thermodynamics and dynamics are discussed in detail.In particular,the correlation between various modification strategies and the hydrogen capacity,dehydrogenation enthalpy and temperature,hydriding/dehydriding rates are summarized.In addition,the mechanism of hydrogen storage processes of Mg-based materials is discussed from the aspect of classical kinetic theories and microscope hydrogen transferring behavior.This review concludes with an outlook on the remaining challenge issues and prospects.展开更多
Magnesium(Mg)is the fourth most abundant element in the human body and is important in terms of specific osteogenesis functions.Here,we provide a comprehensive review of the use of magnesium-based biomaterials(MBs)in ...Magnesium(Mg)is the fourth most abundant element in the human body and is important in terms of specific osteogenesis functions.Here,we provide a comprehensive review of the use of magnesium-based biomaterials(MBs)in bone reconstruction.We review the history of MBs and their excellent biocompatibility,biodegradability and osteopromotive properties,highlighting them as candidates for a new generation of biodegradable orthopedic implants.In particular,the results reported in the field-specific literature(280 articles)in recent decades are dissected with respect to the extensive variety of MBs for orthopedic applications,including Mg/Mg alloys,bioglasses,bioceramics,and polymer materials.We also summarize the osteogenic mechanism of MBs,including a detailed section on the physiological process,namely,the enhanced osteogenesis,promotion of osteoblast adhesion and motility,immunomodulation,and enhanced angiogenesis.Moreover,the merits and limitations of current bone grafts and substitutes are compared.The objective of this review is to reveal the strong potential of MBs for their use as agents in bone repair and regeneration and to highlight issues that impede their clinical translation.Finally,the development and challenges of MBs for transplanted orthopedic materials are discussed.展开更多
Over the last decade’s magnesium and magnesium based compounds have been intensively investigated as potential hydrogen storage as well as thermal energy storage materials due to their abundance and availability as w...Over the last decade’s magnesium and magnesium based compounds have been intensively investigated as potential hydrogen storage as well as thermal energy storage materials due to their abundance and availability as well as their extraordinary high gravimetric and volumetric storage densities.This review work provides a broad overview of the most appealing systems and of their hydrogenation/dehydrogenation properties.Special emphasis is placed on reviewing the efforts made by the scientific community in improving the material’s thermodynamic and kinetic properties while maintaining a high hydrogen storage capacity.展开更多
Magnesium and magnesium-based alloy hydrides remain attractive hydrogen storage materials owing to high hydrogen capacity and rich reserves in the earth＇s crust. A high stability of hydride and sluggish hydriding/deh...Magnesium and magnesium-based alloy hydrides remain attractive hydrogen storage materials owing to high hydrogen capacity and rich reserves in the earth＇s crust. A high stability of hydride and sluggish hydriding/dehydriding kinetics at practical temperatures for the materials drove researchers into alloying with other elements, using different preparation techniques, using catalyst and thin film hydride to improve the hydrogen absorption/desorption properties. In this review, the development of these approaches and their effects on the thermodynamic and kinetics properties of magnesium and magnesium-based alloy hydrides were descript in details.展开更多
Magnesium-based biomaterials have recently gained great attention as promising candidates for the new generation of biodegradable implants.This study investigated the mechanical performance and biodegradation behaviou...Magnesium-based biomaterials have recently gained great attention as promising candidates for the new generation of biodegradable implants.This study investigated the mechanical performance and biodegradation behaviour of magnesium-zinc/hydroxyapatite(Mg-Zn/HA)composites fabricated by different powder mixing techniques.A single step mixing process involved mechanical alloying or mechanical milling techniques,while double step processing involved a combination of both mechanical alloying and mechanical milling.Optimum mechanical properties of the composite were observed when the powders were prepared using single step processing via mechanical alloying technique.However,Mg-Zn/HA composite fabricated through single step processing via mechanical milling technique was found to have the most desirable low degradation rate coupled with highest bioactivity.The composite achieved the lowest degradation rate of 0.039×10^−3 mm/year as measured by immersion test and 0.0230 mm/year as measured by electrochemical polarization.Ca:P ratio of the composite also slightly more than enough to aid the initial bone mineralization,that is 1:1.76,as the required Ca:P ratio for initial bone mineralization is between 1:1 and 1:1.67.展开更多
The addition of nanoscale additions to magnesium(Mg)based alloys can boost mechanical characteristics without noticeably decreasing ductility.Since Mg is the lightest structural material,the Mg-based nanocomposites(NC...The addition of nanoscale additions to magnesium(Mg)based alloys can boost mechanical characteristics without noticeably decreasing ductility.Since Mg is the lightest structural material,the Mg-based nanocomposites(NCs)with improved mechanical properties are appealing materials for lightweight structural applications.In contrast to conventional Mg-based composites,the incorporation of nano-sized reinforcing particles noticeably boosts the strength of Mg-based nanocomposites without significantly reducing the formability.The present article reviews Mg-based metal matrix nanocomposites(MMNCs)with metallic and ceramic additions,fabricated via both solid-based(sintering and powder metallurgy)and liquid-based(disintegrated melt deposition)technologies.It also reviews strengthening models and mechanisms that have been proposed to explain the improved mechanical characteristics of Mg-based alloys and nanocomposites.Further,synergistic strengthening mecha-nisms in Mg matrix nanocomposites and the dominant equations for quantitatively predicting mechanical properties are provided.Furthermore,this study offers an overview of the creep and fatigue behavior of Mg-based alloys and nanocomposites using both traditional(uniaxial)and depth-sensing indentation techniques.The potential applications of magnesium-based alloys and nanocomposites are also surveyed.展开更多
Hydrogen is an ideal clean energy because of its high calorific value and abundance of sources.However,storing hydrogen in a compact,inexpensive,and safe manner is the main restriction on the extensive utilization of ...Hydrogen is an ideal clean energy because of its high calorific value and abundance of sources.However,storing hydrogen in a compact,inexpensive,and safe manner is the main restriction on the extensive utilization of hydrogen energy.Magnesium(Mg)-based hydrogen storage material is considered a reliable solid hydrogen storage material with the advantages of high hydrogen storage capacity(7.6wt%),good performance,and low cost.However,the high thermodynamic stability and slow kinetics of Mg-based hydrogen storage materials have to be overcome.In this paper,we will review the recent advances in the nanoconfinement of Mg-related hydrogen storage materials by loading Mg particles on different supporting materials,including carbons,metal-organic frameworks,and other materials.Perspectives are also provided for designing high-performance Mg-based materials using nanoconfinement.展开更多
Magnesium and its alloys are the most investigated materials for solid-state hydrogen storage in the form of metal hydrides,but there are still unresolved problems with the kinetics and thermodynamics of hydrogenation...Magnesium and its alloys are the most investigated materials for solid-state hydrogen storage in the form of metal hydrides,but there are still unresolved problems with the kinetics and thermodynamics of hydrogenation and dehydrogenation of this group of materials.Severe plastic deformation(SPD)methods,such as equal-channel angular pressing(ECAP),high-pressure torsion(HPT),intensive rolling,and fast forging,have been widely used to enhance the activation,air resistance,and hydrogenation/dehydrogenation kinetics of Mg-based hydrogen storage materials by introducing ultrafine/nanoscale grains and crystal lattice defects.These severely deformed materials,particularly in the presence of alloying additives or second-phase nanoparticles,can show not only fast hydrogen absorption/desorption kinetics but also good cycling stability.It was shown that some materials that are apparently inert to hydrogen can absorb hydrogen after SPD processing.Moreover,the SPD methods were effectively used for hydrogen binding-energy engineering and synthesizing new magnesium alloys with low thermodynamic stability for reversible low/room-temperature hydrogen storage,such as nanoglasses,high-entropy alloys,and metastable phases including the high-pressureγ-MgH2 polymorph.This work reviews recent advances in the development of Mg-based hydrogen storage materials by SPD processing and discusses their potential in future applications.展开更多
Although Mg-based hydrides are extensively considered as a prospective material for solid-state hydrogen storage and clean energy carriers,their high operating temperature and slow kinetics are the main challenges for...Although Mg-based hydrides are extensively considered as a prospective material for solid-state hydrogen storage and clean energy carriers,their high operating temperature and slow kinetics are the main challenges for practical application.Here,a Mg-Ni based hydride,Mg_(2)NiH_(4) nanoparticles(~100 nm),with dual modification strategies of nanosizing and alloying is successfully prepared via a gas-solid preparation process.It is demonstrated that Mg_(2)NiH_(4) nanoparticles form a unique chain-like structure by oriented stacking and exhibit impressive hydrogen storage performance:it starts to release H2 at~170℃ and completes below 230℃ with a saturated capacity of 3.32 wt%and desorbs 3.14 wt% H_(2) within 1800 s at 200℃.The systematic characterizations of Mg_(2)NiH_(4) nanoparticles at different states reveal the dehydrogenation behavior and demonstrate the excellent structural and hydrogen storage stabilities during the de/hydrogenated process.This research is believed to provide new insights for optimizing the kinetic performance of metal hydrides and novel perspectives for designing highly active and stable hydrogen storage alloys.展开更多
Biodegradable metals such as magnesium(Mg)and its alloys have attracted extensive attention in biomedical research due to their excellent mechanical properties and biodegradability.However,traditional casting,extrusio...Biodegradable metals such as magnesium(Mg)and its alloys have attracted extensive attention in biomedical research due to their excellent mechanical properties and biodegradability.However,traditional casting,extrusion,and commercial processing have limitations in manufacturing components with a complex shape/structure,and these processes may produce defects such as cavities and gas pores which can degrade the properties and usefulness of the products.Compared to conventional techniques,additive manufacturing(AM)can be used to precisely control the geometry of workpieces made of different Mg-based materials with multiple geometric scales and produce desirable medical products for orthopedics,dentistry,and other fields.However,a detailed and thorough understanding of the raw materials,manufacturing processes,properties,and applications is required to foster the production of commercial Mg-based biomedical components by AM.This review summarizes recent advances and important issues pertaining to AM of Mg-based biomedical products and discusses future development and application trends.展开更多
Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural bones.However,the rapid degradation of magnesium alloys in biological media hinders successful implantation.Refinem...Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural bones.However,the rapid degradation of magnesium alloys in biological media hinders successful implantation.Refinement of microstructure,as well as reinforcement particles can significantly improve the degradation rate.In this work,multi-pass friction stir processing(FSP)was proposed to synthesize WE43/nano-hydroxyapatite(n HA)surface composite,the microstructure,reinforced particle distribution,micro-hardness,corrosion behavior and in-vitro bioactivity were studied.The subsequent FSP passes of WE43 alloy and WE43/n HA composite refined the grain size which was reduced by 94.29%and 95.92%(2.63 and 1.88μm,respectively)compared to base metal after three passes.This resulted in increasing the microhardness by 120%(90.86 HV0.1)and 135%(105.59 HV0.1)for the WE43 and WE43-n HA,respectively.It is found that increasing FSP passes improved the uniform distribution of n HA particles within the composite matrix which led to improved corrosion resistance and less degradation rate.The corrosion rate of the FSPed WE43/n HA composite after three passes was reduced by 38.2%(4.13 mm/year)and the degradation rate was reduced by 69.7%(2.87 mm/y).This is attributed to secondary phase(Mg24Y5and Mg41Nd5)particle fragmentation and redistribution,as well as a homogeneous distribution of n HA.Additionally,the growing Ca-P and Mg(OH)2layer formed on the surface represented a protective layer that reduced the degradation rate.The wettability test revealed a relatively hydrophilic surface with water contact angle of 49.1±2.2°compared to 71.2±2.1°for base metal.Also,biomineralization test showed that apatite layer grew after immersion 7d in simulated body fluid with atomic ratio of Ca/P 1.60 approaching the stoichiometric ratio(1.67)indicating superior bioactivity of FSPed WE43/n HA composite after three passes.These results raise that the grain refinement by FSP and introduction of n HA particles significantly improved the degradation 展开更多
Hydrogen holds the advantages of high energy density,great natural abundance and zero emission,making it suitable for large scale and long term energy storage,while its safe and efficient storage is still challenging....Hydrogen holds the advantages of high energy density,great natural abundance and zero emission,making it suitable for large scale and long term energy storage,while its safe and efficient storage is still challenging.Among various solid state hydrogen storage materials,MgH_(2) is promising for industrial applications due to its high gravimetric and volumetric hydrogen densities and the abundance of Mg on earth.However,the practical application of MgH_(2) has been limited by its stable thermodynamics and slow hydrogen desorption kinetics.Nanocatalysis is considered as a promising approach for improving the hydrogen storage performance of MgH_(2) and bringing it closer to the requirements of commercial applications.It is worth mentioning that the recently emerging two-dimensional material,MXene,has showcased exceptional catalytic abilities in modifying the hydrogen storage properties of MgH_(2).Besides,MXene possesses a high surface area,excellent chemical/physical stability,and negatively charged terminating groups,making it an ideal support for the"nanoconfinement"of MgH_(2) or highly active catalysts.Herein,we endeavor to provide a comprehensive overview of recent investigations on MXene-based catalysts and MXene supports for improving the hydrogen sorption properties of Mg/MgH_(2).The mechanisms of hydrogen sorption involved in Mg-MXene based composites are highlighted with special emphases on thermodynamics,kinetics,and catalytic behaviors.The aim of this work is to provide a comprehensive and objective review of researches on the development of high-performance catalysts/supports to improve hydrogen storage performances of Mg/MgH_(2) and to identify the opportunities and challenges for future applications.展开更多
Rare earth elements and transition metals have been found to improve the hydrogen storage characteristics of magnesium-based alloys.This study investigated the Mg-Ho-Fe(MHF) ternary alloy prepared using the vacuum ind...Rare earth elements and transition metals have been found to improve the hydrogen storage characteristics of magnesium-based alloys.This study investigated the Mg-Ho-Fe(MHF) ternary alloy prepared using the vacuum induction melting technique.X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),pressure-composition-temperature(PCT),and differential scanning calorimetry(DSC) were used to analyze the alloy's phase transitions,microstructure,thermodynamics,and kinetic properties.The results reveal that the Mg_(98)Ho_(1.5)Fe_(0.5) alloy forms a solid solution with Ho and Fe in the magnesium matrix.Upon hydrogen absorption,the activated alloy transforms into a mixture of Mg/MgH_(2) phases and nanoscale HoH_(2) phases.Notably,only the MgH_(2) phase decomposes during hydrogen desorption,while the HoH_(2) phase remains unchanged,exhibiting a positive catalytic effect.The alloy demonstrates excellent hydrogen absorption kinetics,achieving a capacity of 5.56 wt% H_(2) within 10 min at 360℃,owing to the combined catalytic effects of Ho and Fe.The activation energy for hydrogen desorption is found to be 135.87 kJ/mol,which is lower than that of the activation energies of pure MgH_(2) and MgFe alloys,indicating an enhancement in desorption kinetics.Moreover,the enthalpy and entropy changes for hydrogen absorption and desorption are determined to be-70.51 kJ/mol H_(2),-125.62 J/(K·mol) H_(2),72.83 kJ/mol H_(2),and 128.95 J/(K·mol) H_(2),respectively.Furthermore,it is worth noting that the thermodynamic properties of the alloy are improved due to the catalytic effect of Ho and Fe.展开更多
The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni substrates.For comparison,the experiments were performed in two variants:(1)us...The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni substrates.For comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)procedure.The high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) atmosphere.During the sessile drop tests,images of the Mg/Ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate couples.Scanning and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified couples.It was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the Ni substrate(an average contact angleθ<90°in<1 s),followed by fast spreading and good wetting over the Ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test temperature.However,in both cases,the deep craters formed in the Ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-Ni alloys suggest a strong dissolution of Ni in liquid Mg and apparent values of the final contact angles measured for the Mg/Ni system.展开更多
Degradable biomaterials have emerged as a promising type of medical materials because of their unique advantages of biocompatibility,biodegradability and biosafety.Owing to their bioabsorbable and biocompatible proper...Degradable biomaterials have emerged as a promising type of medical materials because of their unique advantages of biocompatibility,biodegradability and biosafety.Owing to their bioabsorbable and biocompatible properties,magnesium-based biomaterials are considered as ideal degradable medical implants.However,the rapid corrosion of magnesium-based materials not only limits their clinical application but also necessitates a more specific biological evaluation system and biosafety standard.In this study,extracts of pure Mg and its calcium alloy were prepared using different media based on ISO 10993:12;the Mg^2+ concentration and osmolality of each extract were measured.The biocompatibility was investigated using the MTT assay and xCELLigence real-time cell analysis(RTCA).Cytotoxicity tests were conducted with L929,MG-63 and human umbilical vein endothelial cell lines.The results of the RTCA highly matched with those of the MTT assay and revealed the different dynamic modes of the cytotoxic process,which are related to the differences in the tested cell lines,Mg-based materials and dilution rates of extracts.This study provides an insight on the biocompatibility of biodegradable materials from the perspective of cytotoxic dynamics and suggests the applicability of RTCA for the cytotoxic evaluation of degradable biomaterials.展开更多
Magnesium(Mg)-based implants are highly attractive for the orthopedic field and may replace titanium(Ti)as support for fracture healing.To determine the implant-bone interaction in different bony regions,we implanted ...Magnesium(Mg)-based implants are highly attractive for the orthopedic field and may replace titanium(Ti)as support for fracture healing.To determine the implant-bone interaction in different bony regions,we implanted Mg-based alloy ZX00(Mg<0.5 Zn<0.5 Ca,in wt%)and Ti-screws into the distal epiphysis and distal metaphysis of sheep tibiae.The implant degradation and osseointegration were assessed in vivo and ex vivo after 4,6 and 12weeks,using a combination of clinical computed tomography,medium-resolution micro computed tomography(mCT)and high-resolution synchrotron radiation mCT(SRmCT).Implant volume loss,gas formation and bone growth were evaluated for both implantation sites and each bone region independently.Additionally,histological analysis of bone growth was performed on embedded hard-tissue samples.We demonstrate that in all cases,the degradation rate of ZX00-implants ranges between 0.23 and 0.75mm/year.The highest degradation rates were found in the epiphysis.Bone-to-implant contact varied between the time points and bone types for both materials.Mostly,bone-volume-to-total-volume was higher around Ti-implants.However,we found an increased cortical thickness around the ZX00-screws when compared with the Tiscrews.Our results showed the suitability of ZX00-screws for implantation into the distalmeta-and epiphysis.展开更多
The experimental data in the MgH2-5at%V composite was summarized and used to investigate the kinetic mechanism of hydrogen absorption and desorption using a new model. The research results indicate that a coincidence ...The experimental data in the MgH2-5at%V composite was summarized and used to investigate the kinetic mechanism of hydrogen absorption and desorption using a new model. The research results indicate that a coincidence of the theoretical calculation values with the experimental data has been reached and the rate-limiting step is hydrogen diffusion through the hydride phase （β phase） with the activation energy of 47.2 kJ per mole H2 for absorption and the diffusion of hydrogen in the a solid solution （α phase） with that of 59.1 kJ per mole H2 for desorption. In addition, the hydriding rate of the MgH2-V composite is 2.9 times faster than that of MgH2 powders when compared with their characteristic absorption time directly.展开更多
基金supported by the Chongqing Special Key Project of Technology Innovation and Application Development,China(cstc2019jscx-dxwt B0029)the National Natural Science Foundation of China(51871143)+5 种基金the Science and Technology Committee of Shanghai(19010500400)the Shanghai Rising-Star Program(21QA1403200)Chongqing Research Program of Basic Research and Frontier Technology(No.cstc2019jcyj-msxm X0306)the Start-up Funds of Chongqing University(02110011044171)the Senior Talent Start-up Funds of Jiangsu University(4111310024)the Independent Research Project of State Key Laboratory of Mechanical Transmissions(SKLMT-ZZKT-2021M11)
文摘Mg-based materials are one of the most promising hydrogen storage candidates due to their high hydrogen storage capacity,environmental benignity,and high Clarke number characteristics.However,the limited thermodynamics and kinetic properties pose major challenges for their engineering applications.Herein,we review the recent progress in improving their thermodynamics and kinetics,with an emphasis on the models and the influence of various parameters in the calculated models.Subsequently,the impact of alloying,composite,and nanocrystallization on both thermodynamics and dynamics are discussed in detail.In particular,the correlation between various modification strategies and the hydrogen capacity,dehydrogenation enthalpy and temperature,hydriding/dehydriding rates are summarized.In addition,the mechanism of hydrogen storage processes of Mg-based materials is discussed from the aspect of classical kinetic theories and microscope hydrogen transferring behavior.This review concludes with an outlook on the remaining challenge issues and prospects.
基金financial support from the National Natural Science Foundation of China(No.81672230)the Natural Science Foundation of Chongqing(No.cstc2020jcyjmsxm2234)+1 种基金the Top-notch Young Talent Project of Chongqing Traditional Chinese Medicine Hospital(No.CQSZYY2020008)the Chongqing Graduate Research Innovation Project(No.CYS20199)。
文摘Magnesium(Mg)is the fourth most abundant element in the human body and is important in terms of specific osteogenesis functions.Here,we provide a comprehensive review of the use of magnesium-based biomaterials(MBs)in bone reconstruction.We review the history of MBs and their excellent biocompatibility,biodegradability and osteopromotive properties,highlighting them as candidates for a new generation of biodegradable orthopedic implants.In particular,the results reported in the field-specific literature(280 articles)in recent decades are dissected with respect to the extensive variety of MBs for orthopedic applications,including Mg/Mg alloys,bioglasses,bioceramics,and polymer materials.We also summarize the osteogenic mechanism of MBs,including a detailed section on the physiological process,namely,the enhanced osteogenesis,promotion of osteoblast adhesion and motility,immunomodulation,and enhanced angiogenesis.Moreover,the merits and limitations of current bone grafts and substitutes are compared.The objective of this review is to reveal the strong potential of MBs for their use as agents in bone repair and regeneration and to highlight issues that impede their clinical translation.Finally,the development and challenges of MBs for transplanted orthopedic materials are discussed.
文摘Over the last decade’s magnesium and magnesium based compounds have been intensively investigated as potential hydrogen storage as well as thermal energy storage materials due to their abundance and availability as well as their extraordinary high gravimetric and volumetric storage densities.This review work provides a broad overview of the most appealing systems and of their hydrogenation/dehydrogenation properties.Special emphasis is placed on reviewing the efforts made by the scientific community in improving the material’s thermodynamic and kinetic properties while maintaining a high hydrogen storage capacity.
基金financially supported by the National Natural Science Foundation of China (Nos. 51161015 and 51371094)
文摘Magnesium and magnesium-based alloy hydrides remain attractive hydrogen storage materials owing to high hydrogen capacity and rich reserves in the earth＇s crust. A high stability of hydride and sluggish hydriding/dehydriding kinetics at practical temperatures for the materials drove researchers into alloying with other elements, using different preparation techniques, using catalyst and thin film hydride to improve the hydrogen absorption/desorption properties. In this review, the development of these approaches and their effects on the thermodynamic and kinetics properties of magnesium and magnesium-based alloy hydrides were descript in details.
基金The authors would like thank to Universiti Sains Malaysia for FRGS Grant No.203/PBAHAN/6071386 and financial scholarship from Ministry of Higher Education of Malaysia.
文摘Magnesium-based biomaterials have recently gained great attention as promising candidates for the new generation of biodegradable implants.This study investigated the mechanical performance and biodegradation behaviour of magnesium-zinc/hydroxyapatite(Mg-Zn/HA)composites fabricated by different powder mixing techniques.A single step mixing process involved mechanical alloying or mechanical milling techniques,while double step processing involved a combination of both mechanical alloying and mechanical milling.Optimum mechanical properties of the composite were observed when the powders were prepared using single step processing via mechanical alloying technique.However,Mg-Zn/HA composite fabricated through single step processing via mechanical milling technique was found to have the most desirable low degradation rate coupled with highest bioactivity.The composite achieved the lowest degradation rate of 0.039×10^−3 mm/year as measured by immersion test and 0.0230 mm/year as measured by electrochemical polarization.Ca:P ratio of the composite also slightly more than enough to aid the initial bone mineralization,that is 1:1.76,as the required Ca:P ratio for initial bone mineralization is between 1:1 and 1:1.67.
基金H.R.Bakhsheshi-Rad and S.Sharif would like to acknowledge UTM Research Management for the financial support through the funding(Q.J130000.2409.08G37).
文摘The addition of nanoscale additions to magnesium(Mg)based alloys can boost mechanical characteristics without noticeably decreasing ductility.Since Mg is the lightest structural material,the Mg-based nanocomposites(NCs)with improved mechanical properties are appealing materials for lightweight structural applications.In contrast to conventional Mg-based composites,the incorporation of nano-sized reinforcing particles noticeably boosts the strength of Mg-based nanocomposites without significantly reducing the formability.The present article reviews Mg-based metal matrix nanocomposites(MMNCs)with metallic and ceramic additions,fabricated via both solid-based(sintering and powder metallurgy)and liquid-based(disintegrated melt deposition)technologies.It also reviews strengthening models and mechanisms that have been proposed to explain the improved mechanical characteristics of Mg-based alloys and nanocomposites.Further,synergistic strengthening mecha-nisms in Mg matrix nanocomposites and the dominant equations for quantitatively predicting mechanical properties are provided.Furthermore,this study offers an overview of the creep and fatigue behavior of Mg-based alloys and nanocomposites using both traditional(uniaxial)and depth-sensing indentation techniques.The potential applications of magnesium-based alloys and nanocomposites are also surveyed.
基金financially supported by the research programs of the National Natural Science Foundation of China (No. 52101274)the Natural Science Foundation of Shandong Province, China (No. ZR2020QE011)the Youth Top Talent Foundation of Yantai University, China (No. 2219008)
文摘Hydrogen is an ideal clean energy because of its high calorific value and abundance of sources.However,storing hydrogen in a compact,inexpensive,and safe manner is the main restriction on the extensive utilization of hydrogen energy.Magnesium(Mg)-based hydrogen storage material is considered a reliable solid hydrogen storage material with the advantages of high hydrogen storage capacity(7.6wt%),good performance,and low cost.However,the high thermodynamic stability and slow kinetics of Mg-based hydrogen storage materials have to be overcome.In this paper,we will review the recent advances in the nanoconfinement of Mg-related hydrogen storage materials by loading Mg particles on different supporting materials,including carbons,metal-organic frameworks,and other materials.Perspectives are also provided for designing high-performance Mg-based materials using nanoconfinement.
基金supported in part by the Light Metals Educational Foundation of Japan,and in part by the MEXT,Japan through Grants-in-Aid for Scientific Research on Innovative Areas(Nos.JP19H05176&JP21H00150)the Challenging Research Exploratory(Grant No.JP22K18737)+6 种基金W.J.Botta is grateful to the Brazilian agencies FAPESP(Grant No.2013/05987-8)CNPq(Grant Nos.421181-2018-4 and 307397-2019-0)the financial support and to the Laboratory of Structural Characterization(LCE-DEMa-UFSCar)for general electron microscopy facilities.R.Floriano thanks for the financial support from FAPESP(Grant No.2022/01351-0)support from the French State through the ANR-21-CE08-0034-01 project as well as the program“Investment in the future”operated by the National Research Agency(ANR)referenced under No.ANR-11-LABX-0008-01(Labex DAMAS)support from the National Natural Science Foundation of China(Grant No.52171205)support from the National Natural Science Foundation of China(Grant No.52071157).
文摘Magnesium and its alloys are the most investigated materials for solid-state hydrogen storage in the form of metal hydrides,but there are still unresolved problems with the kinetics and thermodynamics of hydrogenation and dehydrogenation of this group of materials.Severe plastic deformation(SPD)methods,such as equal-channel angular pressing(ECAP),high-pressure torsion(HPT),intensive rolling,and fast forging,have been widely used to enhance the activation,air resistance,and hydrogenation/dehydrogenation kinetics of Mg-based hydrogen storage materials by introducing ultrafine/nanoscale grains and crystal lattice defects.These severely deformed materials,particularly in the presence of alloying additives or second-phase nanoparticles,can show not only fast hydrogen absorption/desorption kinetics but also good cycling stability.It was shown that some materials that are apparently inert to hydrogen can absorb hydrogen after SPD processing.Moreover,the SPD methods were effectively used for hydrogen binding-energy engineering and synthesizing new magnesium alloys with low thermodynamic stability for reversible low/room-temperature hydrogen storage,such as nanoglasses,high-entropy alloys,and metastable phases including the high-pressureγ-MgH2 polymorph.This work reviews recent advances in the development of Mg-based hydrogen storage materials by SPD processing and discusses their potential in future applications.
基金supported by the National Key R&D Program of China(No.2022YFB3803801)National Natural Science Foundation of China(52071177,21975125 and 52171214)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘Although Mg-based hydrides are extensively considered as a prospective material for solid-state hydrogen storage and clean energy carriers,their high operating temperature and slow kinetics are the main challenges for practical application.Here,a Mg-Ni based hydride,Mg_(2)NiH_(4) nanoparticles(~100 nm),with dual modification strategies of nanosizing and alloying is successfully prepared via a gas-solid preparation process.It is demonstrated that Mg_(2)NiH_(4) nanoparticles form a unique chain-like structure by oriented stacking and exhibit impressive hydrogen storage performance:it starts to release H2 at~170℃ and completes below 230℃ with a saturated capacity of 3.32 wt%and desorbs 3.14 wt% H_(2) within 1800 s at 200℃.The systematic characterizations of Mg_(2)NiH_(4) nanoparticles at different states reveal the dehydrogenation behavior and demonstrate the excellent structural and hydrogen storage stabilities during the de/hydrogenated process.This research is believed to provide new insights for optimizing the kinetic performance of metal hydrides and novel perspectives for designing highly active and stable hydrogen storage alloys.
基金This work was financially supported by the Guangdong Basic and Applied Basic Research Foundation(No.2020B1515120078,2021A1515111140,and 2021B1515120059)National Key Research and Development Project of China(No.2020YFC1107202)+3 种基金Science Research Cultivation Program(PY2022002)Science and Technology Planning Project of Guangzhou(No.202206010030)City University of Hong Kong Donation Research Grants[DONRMG No.9229021 and 9220061]as well as City University of Hong Kong Strategic Research Grant[SRG 7005505].
文摘Biodegradable metals such as magnesium(Mg)and its alloys have attracted extensive attention in biomedical research due to their excellent mechanical properties and biodegradability.However,traditional casting,extrusion,and commercial processing have limitations in manufacturing components with a complex shape/structure,and these processes may produce defects such as cavities and gas pores which can degrade the properties and usefulness of the products.Compared to conventional techniques,additive manufacturing(AM)can be used to precisely control the geometry of workpieces made of different Mg-based materials with multiple geometric scales and produce desirable medical products for orthopedics,dentistry,and other fields.However,a detailed and thorough understanding of the raw materials,manufacturing processes,properties,and applications is required to foster the production of commercial Mg-based biomedical components by AM.This review summarizes recent advances and important issues pertaining to AM of Mg-based biomedical products and discusses future development and application trends.
基金supported by the University Malaya(Grant code:FRGS/1/2022/TK10/UM/02/6)the National Natural Science Foundation of China(Grant No.51275414,No.51605387)Deanship of Scientific Research at King Khalid University for funding this work through the Large Groups Project under grant number RGP.2/303/44。
文摘Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural bones.However,the rapid degradation of magnesium alloys in biological media hinders successful implantation.Refinement of microstructure,as well as reinforcement particles can significantly improve the degradation rate.In this work,multi-pass friction stir processing(FSP)was proposed to synthesize WE43/nano-hydroxyapatite(n HA)surface composite,the microstructure,reinforced particle distribution,micro-hardness,corrosion behavior and in-vitro bioactivity were studied.The subsequent FSP passes of WE43 alloy and WE43/n HA composite refined the grain size which was reduced by 94.29%and 95.92%(2.63 and 1.88μm,respectively)compared to base metal after three passes.This resulted in increasing the microhardness by 120%(90.86 HV0.1)and 135%(105.59 HV0.1)for the WE43 and WE43-n HA,respectively.It is found that increasing FSP passes improved the uniform distribution of n HA particles within the composite matrix which led to improved corrosion resistance and less degradation rate.The corrosion rate of the FSPed WE43/n HA composite after three passes was reduced by 38.2%(4.13 mm/year)and the degradation rate was reduced by 69.7%(2.87 mm/y).This is attributed to secondary phase(Mg24Y5and Mg41Nd5)particle fragmentation and redistribution,as well as a homogeneous distribution of n HA.Additionally,the growing Ca-P and Mg(OH)2layer formed on the surface represented a protective layer that reduced the degradation rate.The wettability test revealed a relatively hydrophilic surface with water contact angle of 49.1±2.2°compared to 71.2±2.1°for base metal.Also,biomineralization test showed that apatite layer grew after immersion 7d in simulated body fluid with atomic ratio of Ca/P 1.60 approaching the stoichiometric ratio(1.67)indicating superior bioactivity of FSPed WE43/n HA composite after three passes.These results raise that the grain refinement by FSP and introduction of n HA particles significantly improved the degradation
基金the support from the National Natural Science Foundation(No.52171186)National Key Research&Development Program(2022YFB3803700)of China.
文摘Hydrogen holds the advantages of high energy density,great natural abundance and zero emission,making it suitable for large scale and long term energy storage,while its safe and efficient storage is still challenging.Among various solid state hydrogen storage materials,MgH_(2) is promising for industrial applications due to its high gravimetric and volumetric hydrogen densities and the abundance of Mg on earth.However,the practical application of MgH_(2) has been limited by its stable thermodynamics and slow hydrogen desorption kinetics.Nanocatalysis is considered as a promising approach for improving the hydrogen storage performance of MgH_(2) and bringing it closer to the requirements of commercial applications.It is worth mentioning that the recently emerging two-dimensional material,MXene,has showcased exceptional catalytic abilities in modifying the hydrogen storage properties of MgH_(2).Besides,MXene possesses a high surface area,excellent chemical/physical stability,and negatively charged terminating groups,making it an ideal support for the"nanoconfinement"of MgH_(2) or highly active catalysts.Herein,we endeavor to provide a comprehensive overview of recent investigations on MXene-based catalysts and MXene supports for improving the hydrogen sorption properties of Mg/MgH_(2).The mechanisms of hydrogen sorption involved in Mg-MXene based composites are highlighted with special emphases on thermodynamics,kinetics,and catalytic behaviors.The aim of this work is to provide a comprehensive and objective review of researches on the development of high-performance catalysts/supports to improve hydrogen storage performances of Mg/MgH_(2) and to identify the opportunities and challenges for future applications.
基金Project supported by the Fundamental Research Program of Shanxi Province (202203021211193,202203021211190)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(2022L291,2022L274)+1 种基金the National Natural Science Foundation of China (51761032,51871125,52071227)the Key Scientific Research Project in Shanxi Province(202102050201003)。
文摘Rare earth elements and transition metals have been found to improve the hydrogen storage characteristics of magnesium-based alloys.This study investigated the Mg-Ho-Fe(MHF) ternary alloy prepared using the vacuum induction melting technique.X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),pressure-composition-temperature(PCT),and differential scanning calorimetry(DSC) were used to analyze the alloy's phase transitions,microstructure,thermodynamics,and kinetic properties.The results reveal that the Mg_(98)Ho_(1.5)Fe_(0.5) alloy forms a solid solution with Ho and Fe in the magnesium matrix.Upon hydrogen absorption,the activated alloy transforms into a mixture of Mg/MgH_(2) phases and nanoscale HoH_(2) phases.Notably,only the MgH_(2) phase decomposes during hydrogen desorption,while the HoH_(2) phase remains unchanged,exhibiting a positive catalytic effect.The alloy demonstrates excellent hydrogen absorption kinetics,achieving a capacity of 5.56 wt% H_(2) within 10 min at 360℃,owing to the combined catalytic effects of Ho and Fe.The activation energy for hydrogen desorption is found to be 135.87 kJ/mol,which is lower than that of the activation energies of pure MgH_(2) and MgFe alloys,indicating an enhancement in desorption kinetics.Moreover,the enthalpy and entropy changes for hydrogen absorption and desorption are determined to be-70.51 kJ/mol H_(2),-125.62 J/(K·mol) H_(2),72.83 kJ/mol H_(2),and 128.95 J/(K·mol) H_(2),respectively.Furthermore,it is worth noting that the thermodynamic properties of the alloy are improved due to the catalytic effect of Ho and Fe.
基金supported by the National Science Centre of Poland within OPUS 16 Project,no.2018/31/B/ST8/01172。
文摘The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni substrates.For comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)procedure.The high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) atmosphere.During the sessile drop tests,images of the Mg/Ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate couples.Scanning and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified couples.It was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the Ni substrate(an average contact angleθ<90°in<1 s),followed by fast spreading and good wetting over the Ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test temperature.However,in both cases,the deep craters formed in the Ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-Ni alloys suggest a strong dissolution of Ni in liquid Mg and apparent values of the final contact angles measured for the Mg/Ni system.
基金supported by the National Key Research and Development Project of China(NO.2016YFC1103205).
文摘Degradable biomaterials have emerged as a promising type of medical materials because of their unique advantages of biocompatibility,biodegradability and biosafety.Owing to their bioabsorbable and biocompatible properties,magnesium-based biomaterials are considered as ideal degradable medical implants.However,the rapid corrosion of magnesium-based materials not only limits their clinical application but also necessitates a more specific biological evaluation system and biosafety standard.In this study,extracts of pure Mg and its calcium alloy were prepared using different media based on ISO 10993:12;the Mg^2+ concentration and osmolality of each extract were measured.The biocompatibility was investigated using the MTT assay and xCELLigence real-time cell analysis(RTCA).Cytotoxicity tests were conducted with L929,MG-63 and human umbilical vein endothelial cell lines.The results of the RTCA highly matched with those of the MTT assay and revealed the different dynamic modes of the cytotoxic process,which are related to the differences in the tested cell lines,Mg-based materials and dilution rates of extracts.This study provides an insight on the biocompatibility of biodegradable materials from the perspective of cytotoxic dynamics and suggests the applicability of RTCA for the cytotoxic evaluation of degradable biomaterials.
基金supported by the European Training Network‘Promoting patient safety by a novel combination of imaging technologies for biodegradable magnesium implants,MgSafe’(Horizon 2020 Marie Skłodowska-Curie Action(MSCA)grant No.811226(www.mgsafe.eu))and the Laura Bassi Center of Expertise BRIC(Bioresorbable Implants for Children,FFG,Austria)This research was supported in part through the Maxwell computational resources operated at DESY。
文摘Magnesium(Mg)-based implants are highly attractive for the orthopedic field and may replace titanium(Ti)as support for fracture healing.To determine the implant-bone interaction in different bony regions,we implanted Mg-based alloy ZX00(Mg<0.5 Zn<0.5 Ca,in wt%)and Ti-screws into the distal epiphysis and distal metaphysis of sheep tibiae.The implant degradation and osseointegration were assessed in vivo and ex vivo after 4,6 and 12weeks,using a combination of clinical computed tomography,medium-resolution micro computed tomography(mCT)and high-resolution synchrotron radiation mCT(SRmCT).Implant volume loss,gas formation and bone growth were evaluated for both implantation sites and each bone region independently.Additionally,histological analysis of bone growth was performed on embedded hard-tissue samples.We demonstrate that in all cases,the degradation rate of ZX00-implants ranges between 0.23 and 0.75mm/year.The highest degradation rates were found in the epiphysis.Bone-to-implant contact varied between the time points and bone types for both materials.Mostly,bone-volume-to-total-volume was higher around Ti-implants.However,we found an increased cortical thickness around the ZX00-screws when compared with the Tiscrews.Our results showed the suitability of ZX00-screws for implantation into the distalmeta-and epiphysis.
基金This project was financially supported by the Science and Technology Committee of Shanghai (No.0452NM002), China Postdoctoral Science Foundation (No.2004036009), and Shanghai Postdoctoral Science Foundation (No.04R214120).
文摘The experimental data in the MgH2-5at%V composite was summarized and used to investigate the kinetic mechanism of hydrogen absorption and desorption using a new model. The research results indicate that a coincidence of the theoretical calculation values with the experimental data has been reached and the rate-limiting step is hydrogen diffusion through the hydride phase （β phase） with the activation energy of 47.2 kJ per mole H2 for absorption and the diffusion of hydrogen in the a solid solution （α phase） with that of 59.1 kJ per mole H2 for desorption. In addition, the hydriding rate of the MgH2-V composite is 2.9 times faster than that of MgH2 powders when compared with their characteristic absorption time directly.
