In this study,MXene-derived V_(2)O_(5)@C nanosheets are successfully synthesized as an efficient catalyst for enhancing the hydrogen storage performance of Mg H_(2).Mg H_(2)-V_(2)O_(5)@C exhibits exceptional kinetic a...In this study,MXene-derived V_(2)O_(5)@C nanosheets are successfully synthesized as an efficient catalyst for enhancing the hydrogen storage performance of Mg H_(2).Mg H_(2)-V_(2)O_(5)@C exhibits exceptional kinetic and cyclic performance.It desorbs 3.59 wt.%H_(2)within 120 min at200℃and adsorbs 3.9 wt.%H_(2)within 2.7 h at room temperature after complete dehydrogenation.Moreover,even after 251 cycles at 300℃,it maintains a hydrogen capacity of 5.45 wt.%,which accounted for 90.5%of the maximum hydrogen capacity.In addition,an activation mechanism for Mg hydrogenation driven by phase transition from V_(2)O_(3)to VO is firstly clarified through experimental and theoretical analysis.DFT calculations show that the hydrogenation energy barrier of VO(1.01 eV)is significantly lower than that of V_(2)O_(3)(1.82 eV).The phase transition from V_(2)O_(3)to VO forms abundant strong hydrogenation sites,effectively reducing the hydrogenation energy barrier of magnesium and activating the hydrogenation ability of deactivated magnesium.Therefore,benefited from the activation mechanism driven by the VO/V_(2)O_(3)interface,the hydrogen storage capacity of magnesium increased from 4.28 wt.%at 46th cycle to 5.45 wt.%at 251st cycle.?2024 Chongqing University.Publishing services provided by Elsevier B.V.on behalf of Ke Ai Communications Co.Ltd.展开更多
The synthesis of Al2O3-coated and uncoated LiMn2O4 by solid-state method and fabrication of LiMn2O4/graphite battery were described. The structure and morphology of the powders were characterized by X-ray diffraction ...The synthesis of Al2O3-coated and uncoated LiMn2O4 by solid-state method and fabrication of LiMn2O4/graphite battery were described. The structure and morphology of the powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The electrochemical and overcharge performances of Al2O3-coated and uncoated LiMn2O4 batteries were investigated and compared. The uncoated LiMn2O4 battery shows capacity loss of 16.5% after 200 cycles, and the coated LiMn2O4 battery only shows 12.5% after 200 cycles. The uncoated LiMn2O4 battery explodes and creates carbon, MnO, and Li2CO3 after 3C/10 V overcharged test, while the coated LiMn2O4 battery passes the test. The steadier structure, polarization of electrode and modified layer are responsible for the safety performance.展开更多
A new Fe3C-N-doped reduced graphene oxide(Fe3C-N-rGO)prepared by a facile method is used as a separator for high performance lithium-sulfur(Li-S)batteries.The Fe3C-N-rGO is coated on the surface of commercial polyprop...A new Fe3C-N-doped reduced graphene oxide(Fe3C-N-rGO)prepared by a facile method is used as a separator for high performance lithium-sulfur(Li-S)batteries.The Fe3C-N-rGO is coated on the surface of commercial polypropylene separator(Celgard 2400)close to the sulfur cathode.The special nanotubes are in-situ catalyzed by Fe3C nanoparticles.They could entrap lithium polysulfides(Li PSs)to restrain the shuttle effect and reduce the loss of active material.The battery with the modified separator and sulfur cathode shows an excellent cycle performance.It has a high rate performance,580.5 mAh/g at the high current rate of 4 C relative to 1075 mAh/g at 0.1 C.It also has an initial discharge capacity of 774.8 m Ah/g measured at 0.5 C and remains 721.8 mAh/g after 100 cycles with a high capacity retention of 93.2%.The outstanding performances are notable in recently reports with modified separator.展开更多
Biphasic layered oxide cathodes,known for their superior electrochemical performance,are prime candidates for commercializing in Na-ion batteries.Herein,we unveil a series of P3/P2 monophasic and biphasic Al-substitut...Biphasic layered oxide cathodes,known for their superior electrochemical performance,are prime candidates for commercializing in Na-ion batteries.Herein,we unveil a series of P3/P2 monophasic and biphasic Al-substituted Na_(3/4)Mn_(5-x/8)Al_(2x/8)Ni_(3-x/8)O_(2)layered oxide cathodes that lie along the‘zero Mn^(3+)line’in the Na_(3/4)(Mn-Al-Ni)O_(2)pseudo-ternary system.The structural analysis showed a larger Na^(+)conduction bottleneck area in both P3 and P2 structures with a higher Al3+content,which enhanced their rate performance.In each composition,the P3/P2 biphasic compound with nearly equal fractions of P3 and P2 phases outperformed their monophasic counterparts in almost all electrochemical performance parameters.Operando synchrotron XRD measurements obtained for the monophasic P3 and biphasic P2/P3 samples revealed the absence of the O3 phase during cycling.The high structure stability and faster Na^(+)transport kinetics in the biphasic samples underpins the enhancement of electrochemical properties in the Al-substituted P3/P2 cathodes.These results highlight fixed oxidation state lines as a novel tool to identify and design layered oxide cathodes for Na-ion batteries in pseudo-ternary diagrams involving Jahn-Teller active cations.展开更多
O3-type layered oxide cathodes have been widely investigated due to their high reversible capacities and sufficient Na+reservoirs.However,such materials usually suffer from complex multistep phase transitions along wi...O3-type layered oxide cathodes have been widely investigated due to their high reversible capacities and sufficient Na+reservoirs.However,such materials usually suffer from complex multistep phase transitions along with drastic volume changes,leading to the unsatisfied cycle performance.Herein,we report a Mg/Ti co-doped O3-type NaNi_(0.5)Mn_(0.5)O_(2),which can effectively suppress the complex multistep phase transition and realize a solid-solution reaction within a wide voltage range.It is confirmed that,the Mg/Ti co-doping is beneficial to enhance the structural stability and integrity by absorbing micro-strain and distortions.Thus,the as obtained sample delivers an outstanding cyclic performance(82.3%after 200 cycles at 1 C)in the voltage range of 2.0-4.0 V,and a high discharge capacity of 86.6 mAh/g after 100 cycles within the wide voltage range(2.0-4.5 V),which outperform the existing literatures.This co-doping strategy offers new insights into high performance O3-type cathode for sodium ion batteries.展开更多
Nowadays,the majority of the studies on the substitution are focused on cations(such as Y^(3+),Ti^(4+),P^(5+),etc.)in Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),while there are few studies on the substitution of anion...Nowadays,the majority of the studies on the substitution are focused on cations(such as Y^(3+),Ti^(4+),P^(5+),etc.)in Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),while there are few studies on the substitution of anion O^(2-).In this work,the modified LATP with a series of LiCl(LATPClx,x=0.1,0.2,0.3,0.4)additives is prepared to enhance ionic conductivity.The successful introduction of Cl-makes the length of the c axis decrease from 20.822(2)to 20.792(1)Å,and the bulk conductivity of 2.13×10^(-3) S·cm^(-1) is achieved in LATPCl_(0.3).Moreover,the Al/Ti-O1/Cl1 and Al/Ti-O_(2)/Cl_(2) distance decrease,while the Li1-O_(2)/Cl_(2) distance increases.Lithium ions migrate more easily in the nanochannel of M3-M1-M3.In addition,the LiCl additive increases the relative density and the grain boundary conductivity of LATPClx compounds.Naturally,a higher ionic conductivity of 2.12×10^(–4) S·cm^(-1) and a low activation energy of 0.30 eV are obtained in LATPCl_(0.3).Correspondingly,the symmetric cell exhibits a low overpotential of±50 mV for over 200 h in LATPCl_(0.3).The solid-state Li|LATPCl_(0.3)|NCM811(NCM811=LiNi0.8Co0.1Mn0.1O_(2))battery exhibits high initial capacity 185.1 mAh·g^(-1) with a capacity retention rate of 95.4%after 100 cycles at 0.5 C.This result suggests that LiCl additive is an effective strategy to promote electrochemical properties of LATP solid electrolyte and can be considered for reference to other inorganic solid electrolytes systems.展开更多
As a typical two-dimensional(2D)transition metal dichalcogenides(TMDCs)material with nonzero band gap,MoS_(2)has a wide range of potential applications as building blocks in the field of nanoelectronics.The stability ...As a typical two-dimensional(2D)transition metal dichalcogenides(TMDCs)material with nonzero band gap,MoS_(2)has a wide range of potential applications as building blocks in the field of nanoelectronics.The stability and reliability of the corresponding nanoelectronic devices depend critically on the mechanical performance and cyclic reliability of 2D MoS_(2).Although an in situ technique has been used to analyze the mechanical properties of 2D materials,the cyclic mechanical behavior,that is,fatigue,remains a major challenge in the practical application of the devices.This study was aimed at analyzing the planar cyclic performance and deformation behavior of three-layer MoS_(2)nanosheets(NSs)using an in situ transmission electron microscopy(TEM)variable-amplitude uniaxial low-frequency and cyclic loading-unloading tensile acceleration test.We also elucidated the strengthening effect of the natural overlaying affix fragments(other external NSs)or wrinkle folds(internal folds from the NS itself)on cycling performances and service life of MoS_(2)NSs by delaying the whole process of fatigue crack initiation,propagation,and fracture.The results have been confirmed by molecular dynamics(MDs)simulations.The overlaying enhancement effect effectively ensures the long-term reliability and stability of nanoelectronic devices made of few-layer 2D materials.展开更多
The pairing of lithium metal anode(LMA)with Ni-rich layered oxide cathodes for constructing lithium metal batteries(LMBs)to achieve energy density over 500 Wh kg^(-1) receives significant attention from both industry ...The pairing of lithium metal anode(LMA)with Ni-rich layered oxide cathodes for constructing lithium metal batteries(LMBs)to achieve energy density over 500 Wh kg^(-1) receives significant attention from both industry and the scientific community.However,notorious problems are exposed in practical conditions,including lean electrolyte/capacity(E/C)ratio(<3 g(Ah)^(-1)),high cathode mass loading(>3 mAh cm^(-2)),and low negative/positive(N/P)ratio(<3),which creates a significant disparity between the current performance of LMBs and the desired requirements for commercial applications.In the review,we present a summary of the recent achievements made in understanding the mechanistic degradation of LMA,followed by practical strategies that are utilized to address these issues.We also consider the detrimental issues of Ni-rich layered oxide cathodes.Furthermore,we highlight current progresses in the field of practical LMBs in coin/pouch cells to stimulate further innovation.In the end,we propose the issues and prospects for development from the perspective of practical LMBs.展开更多
Given the increasing attention to the safety issues of lithium-ion batteries(LIBs)and the continuous rise in the price of lithium and its compounds,it is urgent to explore innovative electrochemical energy device alte...Given the increasing attention to the safety issues of lithium-ion batteries(LIBs)and the continuous rise in the price of lithium and its compounds,it is urgent to explore innovative electrochemical energy device alternatives to LIBs.Major efforts have been devoted to developing rechargeable aluminum-ion batteries(AIBs),owing to their low cost and high energy density derived from the 3-electron redox reaction.Moreover,the dendrite-free plating behavior with room-temperature ionic liquid electrolytes endows AIBs with great safety expectations.A marked hurdle persists in the quest for appropriate cathode materials that can effectively accommodate aluminum ion species in AIBs.This review aims to deliver an integrated overview of the state-of-the-art cathode materials for nonaqueous and aqueous AIBs,with a special emphasis on their underlying electrochemical interaction with electrolytes.The strategies adopted to improve the specific capacity and cyclic performances of AIBs are highlighted.Furthermore,future perspectives of AIBs are discussed.展开更多
Reduced web section(RWS)connections can prevent lateral-torsional buckling and web local buckling experienced by reduced beam section(RBS)connections.In RWS connections,removing a large portion of web can result in sh...Reduced web section(RWS)connections can prevent lateral-torsional buckling and web local buckling experienced by reduced beam section(RBS)connections.In RWS connections,removing a large portion of web can result in shear demand intolerance induced to plastic hinge region.The present study aims to resolve the problems of RBS and RWS connections by proposing two new connections:(1)RBS with stiffener(RBS-ST)and(2)RBS with reduced web(RW-RBS)connections.In the first connection(RBS-ST),a series of stiffeners is connected to the beam in the reduced flange region,while the second connection(RW-RBS)considers both a reduction in flanges and a reduction in web.Five beam-to-column joints with three different connections,including RBS,RBS-ST,and RW-RBS connections were considered and simulated in ABAQUS.According to the results,RBS-ST and RW-RBS connections can decrease or even eliminate lateral-torsional buckling and web local buckling in RBS connection.It is important to note that RWRBS connection is more effective in long beams with smaller shear demands in the plastic hinge region.Moreover,results showed that RBS and RW-RBS connections experienced strength degradation at 4%to 5%drift,while no strength degradation was observed in RBS-ST connection until 8%drift.展开更多
Sodium ion batteries(SIBs)have attracted great interest as candidates in stationary energy storage systems relying on low cost,high abundance and outstanding electrochemical properties.The foremost challenge in advanc...Sodium ion batteries(SIBs)have attracted great interest as candidates in stationary energy storage systems relying on low cost,high abundance and outstanding electrochemical properties.The foremost challenge in advanced NIBs lies in developing high-performance and low-cost electrode materials.To accelerate the commercialization of sodium ion batteries,various types of materials are being developed to meet the increasing energy demand.O_(3)-type layered oxide cathode materials show great potential for commercial applications due to their high reversible capacity,moderate operating voltage and easy synthesis,while allowing direct matching of the negative electrode to assemble a full battery.Here,representative progress for Ni/Fe/Mn based O_(3)-type cathode materials have been summarized,and existing problems,challenges and solutions are presented.In addition,the effects of irreversible phase transitions,air stability,structural distortion and ion migration on electrochemical performance are systematically discussed.We hope to provide new design ideas or solutions to advance the commercialization of sodium ion batteries.展开更多
基金financially supported by Chongqing Special Key Project of Technology Innovation and Application Development,China(Grant No.cstc2019jscx-dxwt B0029)the Fundamental Research Funds for the Central Universities(No.2022CDJQY-013)。
文摘In this study,MXene-derived V_(2)O_(5)@C nanosheets are successfully synthesized as an efficient catalyst for enhancing the hydrogen storage performance of Mg H_(2).Mg H_(2)-V_(2)O_(5)@C exhibits exceptional kinetic and cyclic performance.It desorbs 3.59 wt.%H_(2)within 120 min at200℃and adsorbs 3.9 wt.%H_(2)within 2.7 h at room temperature after complete dehydrogenation.Moreover,even after 251 cycles at 300℃,it maintains a hydrogen capacity of 5.45 wt.%,which accounted for 90.5%of the maximum hydrogen capacity.In addition,an activation mechanism for Mg hydrogenation driven by phase transition from V_(2)O_(3)to VO is firstly clarified through experimental and theoretical analysis.DFT calculations show that the hydrogenation energy barrier of VO(1.01 eV)is significantly lower than that of V_(2)O_(3)(1.82 eV).The phase transition from V_(2)O_(3)to VO forms abundant strong hydrogenation sites,effectively reducing the hydrogenation energy barrier of magnesium and activating the hydrogenation ability of deactivated magnesium.Therefore,benefited from the activation mechanism driven by the VO/V_(2)O_(3)interface,the hydrogen storage capacity of magnesium increased from 4.28 wt.%at 46th cycle to 5.45 wt.%at 251st cycle.?2024 Chongqing University.Publishing services provided by Elsevier B.V.on behalf of Ke Ai Communications Co.Ltd.
基金Project(10JDG041) supported by the Advanced Person Fund of Jiangsu University, ChinaProject(2007CB613607) supported by the National Basic Research Program of China
文摘The synthesis of Al2O3-coated and uncoated LiMn2O4 by solid-state method and fabrication of LiMn2O4/graphite battery were described. The structure and morphology of the powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The electrochemical and overcharge performances of Al2O3-coated and uncoated LiMn2O4 batteries were investigated and compared. The uncoated LiMn2O4 battery shows capacity loss of 16.5% after 200 cycles, and the coated LiMn2O4 battery only shows 12.5% after 200 cycles. The uncoated LiMn2O4 battery explodes and creates carbon, MnO, and Li2CO3 after 3C/10 V overcharged test, while the coated LiMn2O4 battery passes the test. The steadier structure, polarization of electrode and modified layer are responsible for the safety performance.
基金supported by the National Natural Science Foundation of China(Grant no.51672075,21271069,51772092,51704106)Science and Technology Program of Hunan Province(Grant no.2015JC3049)
文摘A new Fe3C-N-doped reduced graphene oxide(Fe3C-N-rGO)prepared by a facile method is used as a separator for high performance lithium-sulfur(Li-S)batteries.The Fe3C-N-rGO is coated on the surface of commercial polypropylene separator(Celgard 2400)close to the sulfur cathode.The special nanotubes are in-situ catalyzed by Fe3C nanoparticles.They could entrap lithium polysulfides(Li PSs)to restrain the shuttle effect and reduce the loss of active material.The battery with the modified separator and sulfur cathode shows an excellent cycle performance.It has a high rate performance,580.5 mAh/g at the high current rate of 4 C relative to 1075 mAh/g at 0.1 C.It also has an initial discharge capacity of 774.8 m Ah/g measured at 0.5 C and remains 721.8 mAh/g after 100 cycles with a high capacity retention of 93.2%.The outstanding performances are notable in recently reports with modified separator.
基金the Science and Engineering Research Board(SERB),Govt.of India,for the financial support(grant number:CRG/2021/005548).
文摘Biphasic layered oxide cathodes,known for their superior electrochemical performance,are prime candidates for commercializing in Na-ion batteries.Herein,we unveil a series of P3/P2 monophasic and biphasic Al-substituted Na_(3/4)Mn_(5-x/8)Al_(2x/8)Ni_(3-x/8)O_(2)layered oxide cathodes that lie along the‘zero Mn^(3+)line’in the Na_(3/4)(Mn-Al-Ni)O_(2)pseudo-ternary system.The structural analysis showed a larger Na^(+)conduction bottleneck area in both P3 and P2 structures with a higher Al3+content,which enhanced their rate performance.In each composition,the P3/P2 biphasic compound with nearly equal fractions of P3 and P2 phases outperformed their monophasic counterparts in almost all electrochemical performance parameters.Operando synchrotron XRD measurements obtained for the monophasic P3 and biphasic P2/P3 samples revealed the absence of the O3 phase during cycling.The high structure stability and faster Na^(+)transport kinetics in the biphasic samples underpins the enhancement of electrochemical properties in the Al-substituted P3/P2 cathodes.These results highlight fixed oxidation state lines as a novel tool to identify and design layered oxide cathodes for Na-ion batteries in pseudo-ternary diagrams involving Jahn-Teller active cations.
基金supported by the National Natural Science Foundation of China(Nos.22179077,51774251,21908142)Shanghai Science and Technology Commission’s“2020 Science and Technology In-novation Action Plan”(No.20511104003)Natural Science Foundation in Shanghai(No.21ZR1424200)。
文摘O3-type layered oxide cathodes have been widely investigated due to their high reversible capacities and sufficient Na+reservoirs.However,such materials usually suffer from complex multistep phase transitions along with drastic volume changes,leading to the unsatisfied cycle performance.Herein,we report a Mg/Ti co-doped O3-type NaNi_(0.5)Mn_(0.5)O_(2),which can effectively suppress the complex multistep phase transition and realize a solid-solution reaction within a wide voltage range.It is confirmed that,the Mg/Ti co-doping is beneficial to enhance the structural stability and integrity by absorbing micro-strain and distortions.Thus,the as obtained sample delivers an outstanding cyclic performance(82.3%after 200 cycles at 1 C)in the voltage range of 2.0-4.0 V,and a high discharge capacity of 86.6 mAh/g after 100 cycles within the wide voltage range(2.0-4.5 V),which outperform the existing literatures.This co-doping strategy offers new insights into high performance O3-type cathode for sodium ion batteries.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.51772239,51972262 and 22005186)the 111 Project(No.B14040).
文摘Nowadays,the majority of the studies on the substitution are focused on cations(such as Y^(3+),Ti^(4+),P^(5+),etc.)in Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),while there are few studies on the substitution of anion O^(2-).In this work,the modified LATP with a series of LiCl(LATPClx,x=0.1,0.2,0.3,0.4)additives is prepared to enhance ionic conductivity.The successful introduction of Cl-makes the length of the c axis decrease from 20.822(2)to 20.792(1)Å,and the bulk conductivity of 2.13×10^(-3) S·cm^(-1) is achieved in LATPCl_(0.3).Moreover,the Al/Ti-O1/Cl1 and Al/Ti-O_(2)/Cl_(2) distance decrease,while the Li1-O_(2)/Cl_(2) distance increases.Lithium ions migrate more easily in the nanochannel of M3-M1-M3.In addition,the LiCl additive increases the relative density and the grain boundary conductivity of LATPClx compounds.Naturally,a higher ionic conductivity of 2.12×10^(–4) S·cm^(-1) and a low activation energy of 0.30 eV are obtained in LATPCl_(0.3).Correspondingly,the symmetric cell exhibits a low overpotential of±50 mV for over 200 h in LATPCl_(0.3).The solid-state Li|LATPCl_(0.3)|NCM811(NCM811=LiNi0.8Co0.1Mn0.1O_(2))battery exhibits high initial capacity 185.1 mAh·g^(-1) with a capacity retention rate of 95.4%after 100 cycles at 0.5 C.This result suggests that LiCl additive is an effective strategy to promote electrochemical properties of LATP solid electrolyte and can be considered for reference to other inorganic solid electrolytes systems.
基金the financial supports from the National Key Research and Development Program of China(2018YFA0703503)Overseas Expertise Introduction Projects for Discipline Innovation(111 project,B14003)+2 种基金National Natural Science Foundation of China(51991340,51991342,51527802,51902207,52102230)NSFC/RGC Joint Research Scheme project N_HKU159/22,Natural Science Foundation of Shenzhen(JCYJ20220530154404009)Zhejiang Provincial Natural Science Foundation of China(LQ19E020005).
文摘As a typical two-dimensional(2D)transition metal dichalcogenides(TMDCs)material with nonzero band gap,MoS_(2)has a wide range of potential applications as building blocks in the field of nanoelectronics.The stability and reliability of the corresponding nanoelectronic devices depend critically on the mechanical performance and cyclic reliability of 2D MoS_(2).Although an in situ technique has been used to analyze the mechanical properties of 2D materials,the cyclic mechanical behavior,that is,fatigue,remains a major challenge in the practical application of the devices.This study was aimed at analyzing the planar cyclic performance and deformation behavior of three-layer MoS_(2)nanosheets(NSs)using an in situ transmission electron microscopy(TEM)variable-amplitude uniaxial low-frequency and cyclic loading-unloading tensile acceleration test.We also elucidated the strengthening effect of the natural overlaying affix fragments(other external NSs)or wrinkle folds(internal folds from the NS itself)on cycling performances and service life of MoS_(2)NSs by delaying the whole process of fatigue crack initiation,propagation,and fracture.The results have been confirmed by molecular dynamics(MDs)simulations.The overlaying enhancement effect effectively ensures the long-term reliability and stability of nanoelectronic devices made of few-layer 2D materials.
基金supported by the National Natural Science Foundation of China(52207237).
文摘The pairing of lithium metal anode(LMA)with Ni-rich layered oxide cathodes for constructing lithium metal batteries(LMBs)to achieve energy density over 500 Wh kg^(-1) receives significant attention from both industry and the scientific community.However,notorious problems are exposed in practical conditions,including lean electrolyte/capacity(E/C)ratio(<3 g(Ah)^(-1)),high cathode mass loading(>3 mAh cm^(-2)),and low negative/positive(N/P)ratio(<3),which creates a significant disparity between the current performance of LMBs and the desired requirements for commercial applications.In the review,we present a summary of the recent achievements made in understanding the mechanistic degradation of LMA,followed by practical strategies that are utilized to address these issues.We also consider the detrimental issues of Ni-rich layered oxide cathodes.Furthermore,we highlight current progresses in the field of practical LMBs in coin/pouch cells to stimulate further innovation.In the end,we propose the issues and prospects for development from the perspective of practical LMBs.
基金supported by the BRICS STI Framework Programme(No.52261145703)the National 111 Project(No.B16016).
文摘Given the increasing attention to the safety issues of lithium-ion batteries(LIBs)and the continuous rise in the price of lithium and its compounds,it is urgent to explore innovative electrochemical energy device alternatives to LIBs.Major efforts have been devoted to developing rechargeable aluminum-ion batteries(AIBs),owing to their low cost and high energy density derived from the 3-electron redox reaction.Moreover,the dendrite-free plating behavior with room-temperature ionic liquid electrolytes endows AIBs with great safety expectations.A marked hurdle persists in the quest for appropriate cathode materials that can effectively accommodate aluminum ion species in AIBs.This review aims to deliver an integrated overview of the state-of-the-art cathode materials for nonaqueous and aqueous AIBs,with a special emphasis on their underlying electrochemical interaction with electrolytes.The strategies adopted to improve the specific capacity and cyclic performances of AIBs are highlighted.Furthermore,future perspectives of AIBs are discussed.
基金supported by Ilam University(Iran,Ilam)funded by the Ministry of Science and Technology,Iran(Grant No.04-IRILU-En-000006-21).
文摘Reduced web section(RWS)connections can prevent lateral-torsional buckling and web local buckling experienced by reduced beam section(RBS)connections.In RWS connections,removing a large portion of web can result in shear demand intolerance induced to plastic hinge region.The present study aims to resolve the problems of RBS and RWS connections by proposing two new connections:(1)RBS with stiffener(RBS-ST)and(2)RBS with reduced web(RW-RBS)connections.In the first connection(RBS-ST),a series of stiffeners is connected to the beam in the reduced flange region,while the second connection(RW-RBS)considers both a reduction in flanges and a reduction in web.Five beam-to-column joints with three different connections,including RBS,RBS-ST,and RW-RBS connections were considered and simulated in ABAQUS.According to the results,RBS-ST and RW-RBS connections can decrease or even eliminate lateral-torsional buckling and web local buckling in RBS connection.It is important to note that RWRBS connection is more effective in long beams with smaller shear demands in the plastic hinge region.Moreover,results showed that RBS and RW-RBS connections experienced strength degradation at 4%to 5%drift,while no strength degradation was observed in RBS-ST connection until 8%drift.
基金supported by the National Natural Science Foundation of China(22179077,51774251,21908142)Shanghai Science and Technology Commission’s“2020 Science and Technology In-novation Action Plan”(20511104003)Natural Science Foundation in Shanghai(21ZR1424200).
文摘Sodium ion batteries(SIBs)have attracted great interest as candidates in stationary energy storage systems relying on low cost,high abundance and outstanding electrochemical properties.The foremost challenge in advanced NIBs lies in developing high-performance and low-cost electrode materials.To accelerate the commercialization of sodium ion batteries,various types of materials are being developed to meet the increasing energy demand.O_(3)-type layered oxide cathode materials show great potential for commercial applications due to their high reversible capacity,moderate operating voltage and easy synthesis,while allowing direct matching of the negative electrode to assemble a full battery.Here,representative progress for Ni/Fe/Mn based O_(3)-type cathode materials have been summarized,and existing problems,challenges and solutions are presented.In addition,the effects of irreversible phase transitions,air stability,structural distortion and ion migration on electrochemical performance are systematically discussed.We hope to provide new design ideas or solutions to advance the commercialization of sodium ion batteries.
