Performance comparison of lithium fractionation from magnesium via continuous selective nanofiltration/electrodialysis

Although selective nanofiltration(SNF)and selective electrodialysis(SED)have been widely adopted in the field of Mg^(2+)/Li^(+)separation,their differences have not been illustrated systematically.In this study,for the first time,SNF and SED processes in continuous mode were studied for Li+fractionation from the same brine with high Mg/Li ratios and their differences were discussed in detail.For a fair analysis of the two processes,typical factors were optimized.Specifically,the optimal operating pressure and feed flow rate for SNF were 2.4 MPa and 140 L·h^(-1),respectively,while the optimal cell-pair voltage and replenishment flow rate for SED were 1.0 V and 14 L·h^(-1),respectively.Although the Li^(+)fractionation capacity of the two processes were similar,the selectivity coefficient of SNF was 24.7% higher than that of SED and,thus,the Mg/Li ratio in purified stream of the former was 19.0% lower than that of the latter.Due to higher ion driving force,SED had clear advantages in recovery ratio and concentration effects.Meanwhile,the specific energy consumption of SED was 20.1% lower than that of SNF.This study provided a better understanding and guidance for the application and improvement of the two technologies.

Aqueous electrochemical delithiation of cathode materials as a strategy to selectively recover lithium from waste lithium-ion batteries

Lithium recovery from end-of-life Li-ion batteries(LIBs)through pyro-and hydrometallurgical recycling processes involves several refining stages,with high consumption of reagents and energy.A competitive technological alternative is the electrochemical oxidation of the cathode materials,whereby lithium can be deintercalated and transferred to an electrolyte solution without the aid of chemical extracting compounds.This article investigates the potential to selectively recover Li from LIB cathode materials by direct electrochemical extraction in aqueous solutions.The process allowed to recovering up to 98%of Li from high-purity commercial cathode materials(LiMn_(2)O_(4),LiCoO_(2),and Li Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2))with a faradaic efficiency of 98%and negligible co-extraction of Co,Ni,and Mn.The process was then applied to recover Li from the real waste LIBs black mass obtained by the physical treatment of electric vehicle battery packs.This black mass contained graphite,conductive carbon,and metal impurities from current collectors and steel cases,which significantly influenced the evolution and performances of Li electrochemical extraction.Particularly,due to concomitant oxidation of impurities,lithium extraction yields and faradaic efficiencies were lower than those obtained with high-purity cathode materials.Copper oxidation was found to occur within the voltage range investigated,but it could not quantitatively explain the reduced Li extraction performances.In fact,a detailed investigation revealed that above 1.3 V vs.Ag/Ag Cl,conductive carbon can be oxidized,contributing to the decreased Li extraction.Based on the reported experimental results,guidelines were provided that quantitatively enable the extraction of Li from the black mass,while preventing the simultaneous oxidation of impurities and,consequently,reducing the energy consumption of the proposed Li recovery method.

Understanding the corrosion and bio-corrosion behaviour of Magnesium composites – a critical review

Realising the potential of Magnesium(Mg),several globally leading ventures have invested in the Mg industry,but their relatively poor corrosion resistance is a never ending saga till date.The corrosion and bio-corrosion behaviour of Mg has gained research attention and still remains a hot topic in the application of automobile,aerospace and biomedical industries.The intrinsic high electrochemical nature of Mg limits their utilization in diverse application.This scenario has prompted the development of Mg composites with an aim to achieve superior corrosion and bio-corrosion resistance.The present review enlightens the influence of grain size(GS),secondary phase,texture,type of matrix and reinforcement on the corrosion and bio-corrosion behaviour of Mg composites.Firstly,the corrosion and bio-corrosion behaviour of Mg composites manufactured by primary and secondary processing routes are elucidated.Secondly,the comprehensive corrosion and bio-corrosion mechanisms of these Mg composites are proposed.Thirdly,the individual role of GS,texture and corrosive medium on corrosion and bio-corrosion behaviour of Mg composites are clarified and revealed.The challenges encountered,unanswered issues in this field are explained in detail and accordingly the scope for future research is framed.The review is presented from basic concrete background to advanced corrosion mechanisms with an aim of creating interest among the readers like students,researchers and industry experts from various research backgrounds.Indeed,the corrosion and bio-corrosion behaviour of Mg composites are critically reviewed for the first time to:(i)contribute to the body of knowledge,(ii)foster research and development,(iii)make breakthrough,and(iv)create life changing innovations in the field of Mg composite corrosion.

From Liquid to Solid‑State Lithium Metal Batteries:Fundamental Issues and Recent Developments

The widespread adoption of lithium-ion batteries has been driven by the proliferation of portable electronic devices and electric vehicles,which have increasingly stringent energy density requirements.Lithium metal batteries(LMBs),with their ultralow reduction potential and high theoretical capacity,are widely regarded as the most promising technical pathway for achieving high energy density batteries.In this review,we provide a comprehensive overview of fundamental issues related to high reactivity and migrated interfaces in LMBs.Furthermore,we propose improved strategies involving interface engineering,3D current collector design,electrolyte optimization,separator modification,application of alloyed anodes,and external field regulation to address these challenges.The utilization of solid-state electrolytes can significantly enhance the safety of LMBs and represents the only viable approach for advancing them.This review also encompasses the variation in fundamental issues and design strategies for the transition from liquid to solid electrolytes.Particularly noteworthy is that the introduction of SSEs will exacerbate differences in electrochemical and mechanical properties at the interface,leading to increased interface inhomogeneity—a critical factor contributing to failure in all-solidstate lithium metal batteries.Based on recent research works,this perspective highlights the current status of research on developing high-performance LMBs.

Enabling an Inorganic-Rich Interface via Cationic Surfactant for High-Performance Lithium Metal Batteries

An anion-rich electric double layer(EDL)region is favorable for fabricating an inorganic-rich solid-electrolyte interphase(SEI)towards stable lithium metal anode in ester electrolyte.Herein,cetyltrimethylammonium bromide(CTAB),a cationic surfactant,is adopted to draw more anions into EDL by ionic interactions that shield the repelling force on anions during lithium plating.In situ electrochemical surface-enhanced Raman spectroscopy results combined with molecular dynamics simulations validate the enrichment of NO_(3)^(−)/FSI−anions in the EDL region due to the positively charged CTA^(+).In-depth analysis of SEI structure by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry results confirmed the formation of the inorganic-rich SEI,which helps improve the kinetics of Li^(+)transfer,lower the charge transfer activation energy,and homogenize Li deposition.As a result,the Li||Li symmetric cell in the designed electrolyte displays a prolongated cycling time from 500 to 1300 h compared to that in the blank electrolyte at 0.5 mA cm^(-2) with a capacity of 1 mAh cm^(-2).Moreover,Li||LiFePO_(4) and Li||LiCoO_(2) with a high cathode mass loading of>10 mg cm^(-2) can be stably cycled over 180 cycles.

Effects of conductive agent type on lithium extraction from salt lake brine with LiFePO_(4) electrodes

Electrochemical lithium extraction from salt lakes is an effective strategy for obtaining lithium at a low cost.Nevertheless,the elevated Mg:Li ratio and the presence of numerous coexisting ions in salt lake brines give rise to challenges,such as prolonged lithium extraction periods,diminished lithium extraction efficiency,and considerable environmental pollution.In this work,Li FePO4(LFP)served as the electrode material for electrochemical lithium extraction.The conductive network in the LFP electrode was optimized by adjusting the type of conductive agent.This approach resulted in high lithium extraction efficiency and extended cycle life.When the single conductive agent of acetylene black(AB)or multiwalled carbon nanotubes(MWCNTs)was replaced with the mixed conductive agent of AB/MWCNTs,the average diffusion coefficient of Li+in the electrode increased from 2.35×10^(-9)or 1.77×10^(-9)to 4.21×10^(-9)cm^(2)·s^(-1).At the current density of 20 mA·g^(-1),the average lithium extraction capacity per gram of LFP electrode increased from 30.36 mg with the single conductive agent(AB)to 35.62 mg with the mixed conductive agent(AB/MWCNTs).When the mixed conductive agent was used,the capacity retention of the electrode after 30 cycles reached 82.9%,which was considerably higher than the capacity retention of 65.8%obtained when the single AB was utilized.Meanwhile,the electrode with mixed conductive agent of AB/MWCNTs provided good cycling performance.When the conductive agent content decreased or the loading capacity increased,the electrode containing the mixed conductive agent continued to show excellent electrochemical performance.Furthermore,a self-designed,highly efficient,continuous lithium extraction device was constructed.The electrode utilizing the AB/MWCNT mixed conductive agent maintained excellent adsorption capacity and cycling performance in this device.This work provides a new perspective for the electrochemical extraction of lithium using LFP electrodes.

Advancing sustainability:Magnesium-based solutions for environmental challenges and high-performance technologies in superconductivity

The Journal of Magnesium and Alloys(JMA)is actively dedicated to addressing crucial issues related to energy con-servation,emission reduction,energy crises,and sustainable development[1].Magnesium,recognized as the lightest com-mercial structural metal and a promising energy storage ma-terial,holds immense potential in contributing to strategic objectives such as achieving“carbon neutrality”and the“emission peak”,thus mitigating the ongoing energy cri-sis[2].JMA diligently reports on various research fronts,including magnesium-based structural materials,magnesium batteries,magnesium-based hydrogen storage materials,and magnesium-based superconducting super magnets[3].

Perception of fundamental science to boost lithium metal anodes toward practical application

As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference electrodes.Although lithium anodes are regarded as the holy grail of lithium batteries,decades of exploration have not led to the successful commercialization of LMBs,due mainly to the challenges related to the inherent properties of lithium metal.To pave the way for further investigation,herein,a comprehensive review focusing on the fundamental science of lithium are provided.Firstly,the natures of lithium atoms and their isotopes,lithium clusters and lithium crystals are revisited,especially their structural and energetic properties.Subsequently,the electrochemical properties of lithium metal are reviewed.Numerous important concepts and scientific questions,including the electronic structure of lithium,influence of high pressure and low temperature on the properties of lithium,factors influencing lithium deposition,generation of lithium dendrites,and electrode potential of lithium in different electrolytes,are explained and analyzed in detail.Approaches to improve the performance of lithium anodes and thoughtfulness about the electrode potential in lithium battery research are proposed.

Pyrometallurgical recycling of end-of-life lithium-ion batteries

The global importance of lithium-ion batteries(LIBs)has been increasingly underscored with the advancement of high-performance energy storage technologies.However,the end-of-life of these batteries poses significant challenges from environmental,economic,and resource management perspectives.This review paper focuses on the pyrometallurgy-based recycling process of lithium-ion batteries,exploring the fundamental understanding of this process and the importance of its optimization.Centering on the high energy consumption and emission gas issues of the pyrometallurgical recycling process,we systematically analyzed the capital-intensive nature of this process and the resulting technological characteristics.Furthermore,we conducted an in-depth discussion on the future research directions to overcome the existing technological barriers and limitations.This review will provide valuable insights for researchers and industry stakeholders in the battery recycling field.

Recent progress in the research on magnesium and magnesium alloy foils:A short review

Magnesium and magnesium alloy foils have great potential for application in battery anodes,electromagnetic shielding,optics and acoustics,and biology because of their excellent specific damping,internal dissipation coefficients,magnetic and electrical conductivities,as well as high theoretical specific capacity.However,magnesium alloys exhibit poor deformation ability due to their hexagonal close-packed crystal structure.Preparing magnesium and magnesium alloy foils with thicknesses of less than 0.1 mm is difficult because of surface oxidation and grain growth at high temperatures or severe anisotropy after cold rolling that leads to cracks.Numerous methods have been applied to prepare magnesium alloy foils.They include warm rolling,cold rolling,accumulative roll bonding,electric plastic rolling,and on-line heating rolling.Defects of magnesium and magnesium alloy foils during preparation,such as edge cracks and breakage,are important factors for consideration.Herein,the current status of the research on magnesium and magnesium alloy foils is summarized from the aspects of foil preparation,defect control,performance characterization,and application prospects.The advantages and disadvantages of different preparation methods and defect(edge cracks and breakage)mechanisms in the preparation of foils are identified.

Analytical solution to incident angle quasi-phase-matching engineering for second harmonic generation in a periodic-poled lithium niobate crystal

Phase matching or quasi-phase matching(QPM)is of significant importance to the conversion efficiency of second harmonic generation(SHG)in artificial nonlinear crystals like lithium niobate(LN)crystal or microstructured nonlinear crystals like periodic-poled lithium niobate(PPLN)crystals.In this paper,we propose and show that the incident angle of pump laser light can be harnessed as an alternative versatile tool to engineer QPM for high-efficiency SHG in a PPLN crystal,in addition to conventional means of period adjusting or temperature tuning.A rigorous model is established and analytical solution of the nonlinear conversion efficiency under the small and large signal approximation theory is obtained at different incident angles.The variation of phase mismatching and walk-off length with incident angle or incident wavelength are also explored.Numerical simulations for a PPLN crystal with first order QPM structure are used to confirm our theoretical predictions based on the exact analytical solution of the general large-signal theory.The results show that the narrow-band tunable SHG output covers a range of 532 nm–552.8 nm at the ideal incident angle from 0°to 90°.This theoretical scheme,fully considering the reflection and transmission at the air-crystal interface,would offer an efficient theoretical system to evaluate the nonlinear frequency conversion and help to obtain the maximum SHG conversion efficiency by selecting an optimum incident wavelength and incident angle in a specially designed PPLN crystal,which would be very helpful for the design of tunable narrow-band pulse nanosecond,picosecond,and femtosecond laser devices via PPLN and other microstructured LN crystals.

Inherent thermal-responsive strategies for safe lithium batteries

Safe batteries are the basis for next-generation application scenarios such as portable energy storage devices and electric vehicles,which are crucial to achieving carbon neutralization.Electrolytes,separators,and electrodes as main components of lithium batteries strongly affect the occurrence of safety accidents.Responsive materials,which can respond to external stimuli or environmental change,have triggered extensive attentions recently,holding great promise in facilitating safe and smart batteries.This review thoroughly discusses recent advances regarding the construction of high-safety lithium batteries based on internal thermal-responsive strategies,together with the corresponding changes in electrochemical performance under external stimulus.Furthermore,the existing challenges and outlook for the design of safe batteries are presented,creating valuable insights and proposing directions for the practical implementation of safe lithium batteries.

Review on current development of polybenzimidazole membrane for lithium battery

With the rapid development of portable technology,lithium batteries have emerged as potential candidates for high-performance energy storage systems owing to their high energy density and cycling stability.Among the key components of a lithium battery system,the separator plays a critical role as it directly influences the battery performance benchmark(cycling performance and safety).However,traditional polyolefin separators(polypropylene/polyethylene)are unable to meet the demands of highperformance and safer battery systems due to their poor electrolyte compatibility,thermal runaways,and ultimate growth of dendrites.In contrast,membranes fabricated using polybenzimidazole(PBI)exhibit excellent electrolyte wettability and outstanding thermal dimensional stability,thus holding great potential as separators for high-performance and high-safety batteries.In this paper,we present a comprehensive review of the general requirements for separators,synthesis technology for separators,and research trends focusing PBI membranes in lithium batteries to alleviate the current commercial challenges faced by conventional polyolefin separators.In addition,we discuss the future development direction for PBI battery separators by considering various factors such as production cost,ecological footprint,preparation technology,and battery component compatibility.By exploring these perspectives,we aim to promote the continued application and exploration of PBI-based materials to advance lithium battery technology.

Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS

Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tests and(corrosion)fatigue crack growth tests were conducted.The rolled and transverse surfaces of the materials show distinct corrosion rate differences in the stable corrosion stage,but the truth is the opposite for the initial stage of corrosion.In air,specimen orientations have a significant influence on the plastic deformation mechanisms near the crack tip,which results in different fatigue fracture surfaces and cracking paths.Compared with R-T specimens,N-T specimens show a slower fatigue crack growth(FCG)rate in air,which can be attributed to crack closure effects and deformation twinning near the crack tip.The corrosion environment will not significantly change the main plastic deformation mechanisms for the same type of specimen.However,the FCG rate in phosphate buffer saline(PBS)is one order of magnitude higher than that in air,which is caused by the combined effects of hydrogen-induced cracking and anodic dissolution.Owing to the similar corrosion rates at crack tips,the specimens with different orientations display close FCG rates in PBS.

Comprehensive insights into recent innovations:Magnesium-inclusive high-entropy alloys

This review focuses on thermodynamic and physical parameters,synthesis methods,and reported phases of Magnesium(Mg)containing high-entropy alloys(HEAs).Statistical data of publications concerning Mg-containing HEAs were collected and analyzed.Data on the chemical elements included in Mg-containing HEAs,their theoretical end experimental densities,thermodynamic parameters,physical parameters,fabricated techniques and reported phases were also collected and discussed.On the basis of this information,a new classification for HEAs was proposed.It is also shown that the existing thermodynamic parameters cannot accurately predict the formation of a single phase solid solution for Mg-containing HEAs.The physical parameters of Mg-containing HEAs are within a wide range,and most of the synthesized Mg-containing HEAs have a complex multiphase structure.

Degradation and biocompatibility of one-step electrodeposited magnesium thioctic acid/magnesium hydroxide hybrid coatings on ZE21B alloys for cardiovascular stents

Constructing a functional hybrid coating appears to be a promising strategy for addressing the poor corrosion resistance and insufficient endothelialization of Mg-based stents.Nevertheless,the steps for preparing composite coatings are usually complicated and time-consuming.Herein,a novel composite coating,composed of bioactive magnesium thioctic acid(MTA)layer formed by deposition and corrosion-resistant magnesium hydroxide(Mg(OH)_(2))layer grown in situ,is simply fabricated on ZE21B alloys via one-step electrodeposition.Scanning electron microscopy(SEM)shows that the electrodeposited coating has a compact and uniform structure.And the high adhesion of the MTA/Mg(OH)_(2)hybrid coating is also confirmed by the micro-scratch test.Electrochemical test,scanning kelvin probe(SKP),and hydrogen evolution measurement indicate that the hybrid coating effectively reduces the degradation rate of Mg substrates.Haemocompatibility experiment and cell culture trial detect that the composite coating is of fine biocompatibility.Finally,the preparation mechanism of MTA/Mg(OH)_(2)hybrid coatings is discussed and proposed.This coating shows a great potential application for cardiovascular stents.

Microstructure design of advanced magnesium-air battery anodes

Metal-air battery is an environmental friendly energy storage system with unique open structure.Magnesium(Mg)and its alloys have been extensively attempted as anodes for air batteries due to high theoretical energy density,low cost,and recyclability.However,the study on Mg-air battery(MAB)is still at the laboratory level currently,mainly owing to the low anodic efficiency caused by the poor corrosion resistance.In order to reduce corrosion losses and achieve optimal utilization efficiency of Mg anode,the design strategies are reviewed from microstructure perspectives.Firstly,the corrosion behaviors have been discussed,especially the negative difference effect derived by hydrogen evolution.Special attention is given to the effect of anode micro-structures on the MAB,which includes grain size,grain orientation,second phases,crystal structure,twins,and dislocations.For further improvement,the discharge performance,long period stacking ordered phase and its enhancing effect are considered.Meanwhile,given the current debates over Mg dendrites,the potential risk,the impact on discharge,and the elimination strategies are discussed.Microstructure control and single crystal would be promising ways for MAB anode.

A comprehensive review on the processing-property relationships of laser strengthened magnesium

Among the existing series of softer metals,magnesium(Mg)has attracted much attention due to its impressive strength-to-weight ratio.However,due to its ease of deformability,Mg tends to suffer from rapid degradation in a wide variety of abrasive and electrochemical environments.One method of improving its surface properties is through surface modification techniques.Among the existing techniques,laser shock peening(LSP)has been one of the most widely utilized processes due to its surface-hardening-like effects.Despite this understanding,a comprehensive review has yet to exist that encapsulates the strengthening mechanism of LSP for Mg and its influence in degradation environments.This review aims to encapsulate the existing research around the LSP field for Mg.Specifically,an understanding of the surface-strengthening effects in relation to its mechanical,tribological,corrosion,and tribo-corrosion characteristics is elucidated.Additionally,the feasibility of LSP for Mg materials in critical industries is also discussed.Through this work,a novel understanding of LSP for Mg can be understood,which can provide a future direction for research in this field.

Photocatalytic application of magnesium spinel ferrite in wastewater remediation:A review

This review paper explores the efficacy of magnesium ferrite-based catalysts in photocatalytic degradation of organic contaminates(antibiotic and dyes).We report the influence of different doping strategies,synthesis methods,and composite materials on the degradation efficiency of these pollutants.Our analysis reveals the versatile and promising nature of magnesium ferrite-based catalysts,offering the valuable insights into their practical application for restoring the environment.Due to the smaller band gap and magnetic nature of magnesium ferrite,it holds the benefit of utilising the broader spectrum of light while also being recoverable.The in-depth analysis of magnesium ferrites'photocatalytic mechanism could lead to the development of cheap and reliable photocatalyst for the wastewater treatment.This concise review offers a thorough summary of the key advancements in this field,highlighting the pivotal role of the magnesium ferrite based photocatalysts in addressing the pressing global issue of organic pollutants in wastewater.

Unlock the full potential of carbon cloth-based scaffolds towards magnesium metal storage via regulation on magnesiophilicity and surface geometric structure

The development of rechargeable magnesium(Mg) batteries is of practical significance to upgrade the electric energy storage devices due to exceptional capacity and abundant resources of Mg-metal anode.However,the reversible Mg electrochemistry suffers from unsatisfied rate capability and lifespan,mainly caused by non-uniform distribution of electrodeposits.In this work,a fresh design concept of threedimensional carbon cloths scaffolds is proposed to overcome the uncontrollable Mg growth via homogenizing electric field and improving magnesiophilicity.A microscopic smooth and nitrogen-containing defective carbonaceous layer is constructed through a facile pyrolysis of ZIF8 on carbon cloths.As revealed by finite element simulation and DFT calculation results,the smooth surface endows with uniform electric field distribution and simultaneously the nitrogen-doping species enable good magnesiophilicity of scaffolds.The fine and uniform Mg nucleus as well as the inner electrodeposit behavior are also disclosed.As a result,an exceptional cycle life of 500 cycles at 4.0 mA cm^(-2) and 4.0 mA h cm^(-2) is firstly realized to our best knowledge.Besides,the functional scaffolds can be cycled for over 2200 h at 2.0 mA cm^(-2) under a normalized capacity of 5.0 mA h cm^(-2),far exceeding previous results.This work offers an effective approach to enable the full potential of carbon cloths-based scaffolds towards metal storage for next generation battery applications.