Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly fo...Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly formation of a trivalent G-quadruplex/hemin DNAzyme for colorimetric detection of Hg^(2+).A hairpin DNA(Hr)was designed with thymine-Hg^(2+)-thymine pairs that catalyzed by Exo III is prompted to happen upon binding Hg^(2+).A released DNA fragment triggers the catalytic assembly of other three hairpins(H1,H2,and H3)to form many trivalent G-quadruplex/hemin DNA enzymes for signal output.The developed sensor shows a dynamic range from 2 pM to 2μM,with an impressively low detection limit of 0.32 pM for Hg^(2+)detection.Such a sensor also has good selectivity toward Hg^(2+)detection in the presence of other common metal ions.This strategy shows the great potential for visual detection with portable type.展开更多
Developing rapid charging and robust electrode materials for Na-ion batteries is of considerable significance in large-scale power electricity fields.Herein,the authors have proposed a multivalenceion intercalation st...Developing rapid charging and robust electrode materials for Na-ion batteries is of considerable significance in large-scale power electricity fields.Herein,the authors have proposed a multivalenceion intercalation strategy to construct threedimensional(3D)Co-MoS2 nanoflowers with tailorable 1T/2H phase and interlayer distance.The as-formed S-Co-S covalent bonds serve as“electric bridges”to accelerate interlayer charge transfer without 1T phase degeneration during sodiation and desodiation.Quantum density functional theory(QDFT)calculations further confirm that the optimal Co-MoS2 nanoflowers possess the highest Na adsorption energy with reduced ionic diffusion barrier.Consequently,they deliver a superior sodiumstorage capacity of 351 mAh g−1 in 0.4-3.0 V even at 20 A g−1 without capacity fading at 5 A g−1 for 2000 cycles.The high electrochemical reversibility of the 1T phase in Co-MoS2,which accounts for such excellent performance,has been unveiled for the first time by in situ Raman spectra.This finding demonstrates important insights onto promoting two-dimensional(2D)nanomaterials toward rapid charging alkali-ion batteries.展开更多
Background The vaccination of mice with DNA encoding single candidate antigens has failed to induce significant protection against Schistosoma japonicum (S. japonicum) challenge infections In this study, we evaluated ...Background The vaccination of mice with DNA encoding single candidate antigens has failed to induce significant protection against Schistosoma japonicum (S. japonicum) challenge infections In this study, we evaluated the feasibility of using a multivalent DNA vaccine which co expressed S japonicum integral membrane protein Sj23 and murine cytokine IL 12 to induce protective immune responses Methods The plasmid pVIVO2 IL12 Sj23, a eukaryotic expression vector expressing Sj23 and murine IL 12 simultaneously, was constructed, identified, and tested for expression in vitro Its ability to protect against S japonicum challenge infections was analyed according to worm reduction rate and egg reduction rate after vaccination of BALB/c mice The serum levels of specific IgG antibody were determined by enzyme linked immuno sorbent assay (ELISA) and Western blot analysis Using cultured spleen cells, IFN γ and IL 4 post stimulation were quantified by ELISA The phenotypes of splenocyte populations were analyzed by flow cytometry (FCM) Results The plasmid DNA pVIVO2 IL12 Sj23 was proven to express well in vitro by transient transfection of HEK 293 cells Immunization resulted in a worm reduction rate of 45 53% and egg reduction rate of 58 35% ELISA and Western blot analysis indicated that immunized mice generated specific IgG against Sj23 Spleen cells showed significant increases in IFN γ but decreases in IL 4 No significant differences in CD4 + and CD8 + subgroup ratios were observed after the challenges Conclusions The multivalent DNA vaccine pVIVO2 IL12 Sj23 is sufficient to elicit moderate but highly significant levels of protective immunity against challenge infections Cytokine IL 12, as a gene adjuvant, was able to enhance the Th1 responses and, hence, the protective immunity展开更多
Hand,foot,and mouth disease(HFMD)recently emerged as a global public threat.The licensure of inactivated enterovirus A71(EV-A71)vaccine was the first step in using a vaccine to control HFMD.New challenges arise from c...Hand,foot,and mouth disease(HFMD)recently emerged as a global public threat.The licensure of inactivated enterovirus A71(EV-A71)vaccine was the first step in using a vaccine to control HFMD.New challenges arise from changes in the pathogen spectrum while vaccines directed against other common serotypes are in the preclinical stage.The mission of a broad-spectrum prevention strategy clearly favors multivalent vaccines.The development of multivalent vaccines was attempted via the simple combination of potent monovalent vaccines or the construction of chimeric vaccines comprised of epitopes derived from different virus serotypes.The present review summarizes recent advances in HFMD vaccine development and discusses the next steps toward a safe and effective HFMD vaccine that is capable of establishing a crossprotective antibody response.展开更多
Although Sn-based catalysts have recently achieved considerable improvement in selective electro-catalyzing CO_(2)into HCOOH,the role of various valence Sn species is not fully understood due to the complexity and unc...Although Sn-based catalysts have recently achieved considerable improvement in selective electro-catalyzing CO_(2)into HCOOH,the role of various valence Sn species is not fully understood due to the complexity and uncertainty of their evolution during the reaction process.Here,inspired by the theoretical simulations that the concomitant multivalent Sn(Sn^(0),Sn^(Ⅱ)and Sn^(Ⅳ))can significantly motivate the intrinsic activity of Sn-based catalyst,the Sn/SnO/SnO_(2)nanosheets were proposed to experimentally verify the synergistic effect of multivalent Sn species on the CO_(2)-into-HCOOH conversion.During CO_(2)reduction reaction,the Sn/SnO/SnO_(2)nanosheets,which are prepared by the sequential hydrothermal reaction,calcined crystallization and low-temperature H_(2)treatment,exhibit a high FEHCOOH of 89.6%at-0.9 VRHE as well as a large cathodic current density.Systematic experimental and theoretical results corroborate that multivalent Sn species synergistically energize the CO_(2)activation,the HCOO*adsorption,and the electron transfer,which make Sn/SnO/SnO_(2)favour the conversion from CO_(2)into HCOOH in both thermodynamics and kinetics.This proof-of-concept study establishes a relationship between the enhanced performance and the multivalent Sn species,and also provides a practicable and scalable avenue for rational engineering high-powered electrocatalysts.展开更多
The constant increase in global energy demand and stricter environmental standards are calling for advanced energy storage technologies that can store electricity from intermittent renewable sources such as wind,solar...The constant increase in global energy demand and stricter environmental standards are calling for advanced energy storage technologies that can store electricity from intermittent renewable sources such as wind,solar,and tidal power,to allow the broader implementation of the renewables.The gridoriented sodium-ion batteries,potassium ion batteries and multivalent ion batteries are cheaper and more sustainable alternatives to Li-ion,although they are still in the early stages of development.Additional optimisation of these battery systems is required,to improve the energy and power density,and to solve the safety issues caused by dendrites growth in anodes.Electrolyte,one of the most critical components in these batteries,could significantly influence the electrochemical performances and operations of batteries.In this review,the definitions and influences of three critical components(salts,solvents,and additives)in electrolytes are discussed.The significant advantages,challenges,recent progress and future optimisation directions of various electrolytes for monovalent and multivalent ions batteries(i.e.organic,ionic liquid and aqueous liquid electrolytes,polymer and inorganic solid electrolytes)are summarised to guide the practical application for grid-oriented batteries.展开更多
MXenes have attracted increasing attention because of their rich surface functional groups,high electrical conductivity,and outstanding dispersibility in many solvents,and have demonstrated competitive efficiency in e...MXenes have attracted increasing attention because of their rich surface functional groups,high electrical conductivity,and outstanding dispersibility in many solvents,and have demonstrated competitive efficiency in energy storage and conversion applications.However,the restacking nature of MXene nanosheets like other two-dimensional(2D)materials through van der Waals forces results in sluggish ionic kinetics,restricted number of active sites,and ultimate deterioration of MXene mate-rial/device performance.The strategy of raising 2D MXenes into three-dimensional(3D)structures has been considered an efficient way for reducing restacking,providing greater porosity,higher surface area,and shorter distances for mass transport of ions,surpassing standard one-dimensional(1D)and 2D structures.In multivalent ion batteries,the positive multivalent ions combine with two or more electrons at the same time,so their capacities are two or three times that of lithium-ion batteries(LIBs)under the same conditions,e.g.,a magnesium ion battery has a high theoretical specific capacity of 2205 mAh g^(−1)and a high volumetric capacity of 3833 mAh cm^(−3).In this review,we summarize the most recent strategies for fabricating 3D MXene architectures,such as assembly,template,3D printing,electrospinning,aerogel,and gas foaming methods.Special consideration has been given to the applications of highly porous 3D MXenes in energy storage devices beyond LIBs,such as sodium ion batteries(SIBs),potassium ion batteries(KIBs),magnesium ion batteries(MIBs),zinc ion batteries(ZIBs),and aluminum ion batteries(AIBs).Finally,the authors provide a summary of the future opportunities and challenges for the construction of 3D MXenes and MXene-based electrodes for applications beyond LIBs.展开更多
Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))(NFPP)is currently drawing increased attention as a sodium-ion batteries(SIBs)cathode due to the cost-effective and NASICON-type structure features.Owing to the sluggish electron an...Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))(NFPP)is currently drawing increased attention as a sodium-ion batteries(SIBs)cathode due to the cost-effective and NASICON-type structure features.Owing to the sluggish electron and Na~+conductivities,however,its real implementation is impeded by the grievous capacity decay and inferior rate capability.Herein,multivalent cation substituted microporous Na_(3.9)Fe_(2.9)Al_(0.1)(PO_(4))_(2)(P_(2)O_(7))(NFAPP)with wide operation-temperature is elaborately designed through regulating structure/interface coupled electron/ion transport.Greatly,the derived Na vacancy and charge rearrangement induced by trivalent Al^(3+)substitution lower the ions diffusion barriers,thereby endowing faster electron transport and Na^(+)mobility.More importantly,the existing Al-O-P bonds strengthen the local environment and alleviate the volume vibration during(de)sodiation,enabling highly reversible valence variation and structural evolution.As a result,remarkable cyclability(over 10,000 loops),ultrafast rate capability(200 C),and exceptional all-climate stability(-40-60℃)in half/full cells are demonstrated.Given this,the rational work might provide an actionable strategy to promote the electrochemical property of NFPP,thus unveiling the great application prospect of sodium iron mixed phosphate materials.展开更多
With the rapid development of portable electronics and electric road vehicles,high-energy-density batteries have been becoming front-burner issues.Traditionally,homogeneous electrolyte cannot simultaneously meet diame...With the rapid development of portable electronics and electric road vehicles,high-energy-density batteries have been becoming front-burner issues.Traditionally,homogeneous electrolyte cannot simultaneously meet diametrically opposed demands of high-potential cathode and low-potential anode,which are essential for high-voltage batteries.Meanwhile,homogeneous electrolyte is difficult to achieve bi-or multi-functions to meet different requirements of electrodes.In comparison,the asymmetric electrolyte with bi-or multi-layer disparate components can satisfy distinct requirements by playing different roles of each electrolyte layer and meanwhile compensates weakness of individual electrolyte.Consequently,the asymmetric electrolyte can not only suppress by-product sedimentation and continuous electrolyte decomposition at the anode while preserving active substances at the cathode for high-voltage batteries with long cyclic lifespan.In this review,we comprehensively divide asymmetric electrolytes into three categories:decoupled liquid-state electrolytes,bi-phase solid/liquid electrolytes and decoupled asymmetric solid-state electrolytes.The design principles,reaction mechanism and mutual compatibility are also studied,respectively.Finally,we provide a comprehensive vision for the simplification of structure to reduce costs and increase device energy density,and the optimization of solvation structure at anolyte/catholyte interface to realize fast ion transport kinetics.展开更多
Lithium-rich cathode oxides with capability to realize multivalent cationic and anionic redox reactions have attracted much attention as promising candidate electrode materials for high energy density lithium ion batt...Lithium-rich cathode oxides with capability to realize multivalent cationic and anionic redox reactions have attracted much attention as promising candidate electrode materials for high energy density lithium ion batteries because of their ultrahigh specific capacity. However, redox reaction mechanisms, especially for the anionic redox reaction of these materials, are still not very clear. Meanwhile, several pivotal challenges associated with the redox reactions mechanisms, such as structural instability and limited cycle life, hinder the practical applications of these high-capacity lithium-rich cathode oxides. Herein, we review the lithium-rich oxides with various crystal structures. The multivalent cationic/anionic redox reaction mechanisms of several representative high capacity lithium-rich cathode oxides are discussed, attempting to understand the origins of the high lithium storage capacities of these materials. In addition, we provide perspectives for the further development of these lithium-rich cathode oxides based on multivalent cationic and anionic redox reactions, focusing on addressing the fundamental problems and promoting their practical applications.展开更多
基金Supported by The Science and Technology Project of General Administration of Quality Supervision,Inspection and Quarantine (2015IK126)The Science and Technology Project of Changsha City of Hunan Province of China (KQ1602124).
文摘Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly formation of a trivalent G-quadruplex/hemin DNAzyme for colorimetric detection of Hg^(2+).A hairpin DNA(Hr)was designed with thymine-Hg^(2+)-thymine pairs that catalyzed by Exo III is prompted to happen upon binding Hg^(2+).A released DNA fragment triggers the catalytic assembly of other three hairpins(H1,H2,and H3)to form many trivalent G-quadruplex/hemin DNA enzymes for signal output.The developed sensor shows a dynamic range from 2 pM to 2μM,with an impressively low detection limit of 0.32 pM for Hg^(2+)detection.Such a sensor also has good selectivity toward Hg^(2+)detection in the presence of other common metal ions.This strategy shows the great potential for visual detection with portable type.
基金This study was supported by the National Natural Science Foundation of China(nos.51672082,21975074,and 91534202)the Basic Research Program of Shanghai(no.17JC1402300)+1 种基金the Shanghai Scientific and Technological Innovation Project(no.18JC1410500)the National Program for Support of Top-Notch Young Professionals,and the Fundamental Research Funds for the Central Universities(no.222201718002).
文摘Developing rapid charging and robust electrode materials for Na-ion batteries is of considerable significance in large-scale power electricity fields.Herein,the authors have proposed a multivalenceion intercalation strategy to construct threedimensional(3D)Co-MoS2 nanoflowers with tailorable 1T/2H phase and interlayer distance.The as-formed S-Co-S covalent bonds serve as“electric bridges”to accelerate interlayer charge transfer without 1T phase degeneration during sodiation and desodiation.Quantum density functional theory(QDFT)calculations further confirm that the optimal Co-MoS2 nanoflowers possess the highest Na adsorption energy with reduced ionic diffusion barrier.Consequently,they deliver a superior sodiumstorage capacity of 351 mAh g−1 in 0.4-3.0 V even at 20 A g−1 without capacity fading at 5 A g−1 for 2000 cycles.The high electrochemical reversibility of the 1T phase in Co-MoS2,which accounts for such excellent performance,has been unveiled for the first time by in situ Raman spectra.This finding demonstrates important insights onto promoting two-dimensional(2D)nanomaterials toward rapid charging alkali-ion batteries.
文摘Background The vaccination of mice with DNA encoding single candidate antigens has failed to induce significant protection against Schistosoma japonicum (S. japonicum) challenge infections In this study, we evaluated the feasibility of using a multivalent DNA vaccine which co expressed S japonicum integral membrane protein Sj23 and murine cytokine IL 12 to induce protective immune responses Methods The plasmid pVIVO2 IL12 Sj23, a eukaryotic expression vector expressing Sj23 and murine IL 12 simultaneously, was constructed, identified, and tested for expression in vitro Its ability to protect against S japonicum challenge infections was analyed according to worm reduction rate and egg reduction rate after vaccination of BALB/c mice The serum levels of specific IgG antibody were determined by enzyme linked immuno sorbent assay (ELISA) and Western blot analysis Using cultured spleen cells, IFN γ and IL 4 post stimulation were quantified by ELISA The phenotypes of splenocyte populations were analyzed by flow cytometry (FCM) Results The plasmid DNA pVIVO2 IL12 Sj23 was proven to express well in vitro by transient transfection of HEK 293 cells Immunization resulted in a worm reduction rate of 45 53% and egg reduction rate of 58 35% ELISA and Western blot analysis indicated that immunized mice generated specific IgG against Sj23 Spleen cells showed significant increases in IFN γ but decreases in IL 4 No significant differences in CD4 + and CD8 + subgroup ratios were observed after the challenges Conclusions The multivalent DNA vaccine pVIVO2 IL12 Sj23 is sufficient to elicit moderate but highly significant levels of protective immunity against challenge infections Cytokine IL 12, as a gene adjuvant, was able to enhance the Th1 responses and, hence, the protective immunity
基金sponsored by the National Natural Science Foundation of China(81672018)the National 13th Five-Year Grand Program on Key Infectious Disease Control(2017ZX10202102)+2 种基金the 13th Five-Year National Science and Technology Major Project for infectious Diseases(2017ZX10305501-002)Shanghai Pujiang Program(19PJ1409100)the Technology Service Platform for Detecting High level Biological Safety Pathogenic Microorganism Supported by Shanghai Science and Technology Commission(18DZ2293000)。
文摘Hand,foot,and mouth disease(HFMD)recently emerged as a global public threat.The licensure of inactivated enterovirus A71(EV-A71)vaccine was the first step in using a vaccine to control HFMD.New challenges arise from changes in the pathogen spectrum while vaccines directed against other common serotypes are in the preclinical stage.The mission of a broad-spectrum prevention strategy clearly favors multivalent vaccines.The development of multivalent vaccines was attempted via the simple combination of potent monovalent vaccines or the construction of chimeric vaccines comprised of epitopes derived from different virus serotypes.The present review summarizes recent advances in HFMD vaccine development and discusses the next steps toward a safe and effective HFMD vaccine that is capable of establishing a crossprotective antibody response.
基金the National Natural Science Foundation of China(Nos.21631004,21901065)the Natural Science Foundation of Heilongjiang Province of China(No.LH2020B019)+1 种基金the Youth Science and Technology Innovation Team Project of Heilongjiang Province(No.RCYJTD201803)the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province(No.UNPYSCT-2018009).
文摘Although Sn-based catalysts have recently achieved considerable improvement in selective electro-catalyzing CO_(2)into HCOOH,the role of various valence Sn species is not fully understood due to the complexity and uncertainty of their evolution during the reaction process.Here,inspired by the theoretical simulations that the concomitant multivalent Sn(Sn^(0),Sn^(Ⅱ)and Sn^(Ⅳ))can significantly motivate the intrinsic activity of Sn-based catalyst,the Sn/SnO/SnO_(2)nanosheets were proposed to experimentally verify the synergistic effect of multivalent Sn species on the CO_(2)-into-HCOOH conversion.During CO_(2)reduction reaction,the Sn/SnO/SnO_(2)nanosheets,which are prepared by the sequential hydrothermal reaction,calcined crystallization and low-temperature H_(2)treatment,exhibit a high FEHCOOH of 89.6%at-0.9 VRHE as well as a large cathodic current density.Systematic experimental and theoretical results corroborate that multivalent Sn species synergistically energize the CO_(2)activation,the HCOO*adsorption,and the electron transfer,which make Sn/SnO/SnO_(2)favour the conversion from CO_(2)into HCOOH in both thermodynamics and kinetics.This proof-of-concept study establishes a relationship between the enhanced performance and the multivalent Sn species,and also provides a practicable and scalable avenue for rational engineering high-powered electrocatalysts.
文摘The constant increase in global energy demand and stricter environmental standards are calling for advanced energy storage technologies that can store electricity from intermittent renewable sources such as wind,solar,and tidal power,to allow the broader implementation of the renewables.The gridoriented sodium-ion batteries,potassium ion batteries and multivalent ion batteries are cheaper and more sustainable alternatives to Li-ion,although they are still in the early stages of development.Additional optimisation of these battery systems is required,to improve the energy and power density,and to solve the safety issues caused by dendrites growth in anodes.Electrolyte,one of the most critical components in these batteries,could significantly influence the electrochemical performances and operations of batteries.In this review,the definitions and influences of three critical components(salts,solvents,and additives)in electrolytes are discussed.The significant advantages,challenges,recent progress and future optimisation directions of various electrolytes for monovalent and multivalent ions batteries(i.e.organic,ionic liquid and aqueous liquid electrolytes,polymer and inorganic solid electrolytes)are summarised to guide the practical application for grid-oriented batteries.
基金supported by the National Natural Science Foundation of China(grant numbers 21703147,U1401248)one of the authors(T.B.)also acknowledges the support of China Scholarship Council(grant number 2018SLJ022487)+2 种基金National Natural Science Foundation of China,U1401248,Lijun GaoNational Natural Science Foundation of China,21703147,Jianqing ZhaoChina Scholarship Council,2018SLJ022487,Tariq Bashir。
文摘MXenes have attracted increasing attention because of their rich surface functional groups,high electrical conductivity,and outstanding dispersibility in many solvents,and have demonstrated competitive efficiency in energy storage and conversion applications.However,the restacking nature of MXene nanosheets like other two-dimensional(2D)materials through van der Waals forces results in sluggish ionic kinetics,restricted number of active sites,and ultimate deterioration of MXene mate-rial/device performance.The strategy of raising 2D MXenes into three-dimensional(3D)structures has been considered an efficient way for reducing restacking,providing greater porosity,higher surface area,and shorter distances for mass transport of ions,surpassing standard one-dimensional(1D)and 2D structures.In multivalent ion batteries,the positive multivalent ions combine with two or more electrons at the same time,so their capacities are two or three times that of lithium-ion batteries(LIBs)under the same conditions,e.g.,a magnesium ion battery has a high theoretical specific capacity of 2205 mAh g^(−1)and a high volumetric capacity of 3833 mAh cm^(−3).In this review,we summarize the most recent strategies for fabricating 3D MXene architectures,such as assembly,template,3D printing,electrospinning,aerogel,and gas foaming methods.Special consideration has been given to the applications of highly porous 3D MXenes in energy storage devices beyond LIBs,such as sodium ion batteries(SIBs),potassium ion batteries(KIBs),magnesium ion batteries(MIBs),zinc ion batteries(ZIBs),and aluminum ion batteries(AIBs).Finally,the authors provide a summary of the future opportunities and challenges for the construction of 3D MXenes and MXene-based electrodes for applications beyond LIBs.
基金supported by the National Natural Science Foundation of China(52325405,52261135632,and U21A20284)the Science and Technology Foundation of Guizhou Province(QKHZC[2020]2Y037)+1 种基金the Fundamental Research Funds for the Central Universities of Central South University(2023XQLH070,2023XQLH069)the U19 station in the National Synchrotron Radiation Laboratory(NSRL)。
文摘Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))(NFPP)is currently drawing increased attention as a sodium-ion batteries(SIBs)cathode due to the cost-effective and NASICON-type structure features.Owing to the sluggish electron and Na~+conductivities,however,its real implementation is impeded by the grievous capacity decay and inferior rate capability.Herein,multivalent cation substituted microporous Na_(3.9)Fe_(2.9)Al_(0.1)(PO_(4))_(2)(P_(2)O_(7))(NFAPP)with wide operation-temperature is elaborately designed through regulating structure/interface coupled electron/ion transport.Greatly,the derived Na vacancy and charge rearrangement induced by trivalent Al^(3+)substitution lower the ions diffusion barriers,thereby endowing faster electron transport and Na^(+)mobility.More importantly,the existing Al-O-P bonds strengthen the local environment and alleviate the volume vibration during(de)sodiation,enabling highly reversible valence variation and structural evolution.As a result,remarkable cyclability(over 10,000 loops),ultrafast rate capability(200 C),and exceptional all-climate stability(-40-60℃)in half/full cells are demonstrated.Given this,the rational work might provide an actionable strategy to promote the electrochemical property of NFPP,thus unveiling the great application prospect of sodium iron mixed phosphate materials.
基金National Natural Science Foundation of China(52202299)the Analytical&Testing Center of Northwestern Polytechnical University(2022T006).
文摘With the rapid development of portable electronics and electric road vehicles,high-energy-density batteries have been becoming front-burner issues.Traditionally,homogeneous electrolyte cannot simultaneously meet diametrically opposed demands of high-potential cathode and low-potential anode,which are essential for high-voltage batteries.Meanwhile,homogeneous electrolyte is difficult to achieve bi-or multi-functions to meet different requirements of electrodes.In comparison,the asymmetric electrolyte with bi-or multi-layer disparate components can satisfy distinct requirements by playing different roles of each electrolyte layer and meanwhile compensates weakness of individual electrolyte.Consequently,the asymmetric electrolyte can not only suppress by-product sedimentation and continuous electrolyte decomposition at the anode while preserving active substances at the cathode for high-voltage batteries with long cyclic lifespan.In this review,we comprehensively divide asymmetric electrolytes into three categories:decoupled liquid-state electrolytes,bi-phase solid/liquid electrolytes and decoupled asymmetric solid-state electrolytes.The design principles,reaction mechanism and mutual compatibility are also studied,respectively.Finally,we provide a comprehensive vision for the simplification of structure to reduce costs and increase device energy density,and the optimization of solvation structure at anolyte/catholyte interface to realize fast ion transport kinetics.
基金supported by the National Key Research and Development Program of China (2016YFA202500)the “One Hundred Talent Project” of the Chinese Academy of Sciencesthe National Natural Science Foundation of China (11675255)
文摘Lithium-rich cathode oxides with capability to realize multivalent cationic and anionic redox reactions have attracted much attention as promising candidate electrode materials for high energy density lithium ion batteries because of their ultrahigh specific capacity. However, redox reaction mechanisms, especially for the anionic redox reaction of these materials, are still not very clear. Meanwhile, several pivotal challenges associated with the redox reactions mechanisms, such as structural instability and limited cycle life, hinder the practical applications of these high-capacity lithium-rich cathode oxides. Herein, we review the lithium-rich oxides with various crystal structures. The multivalent cationic/anionic redox reaction mechanisms of several representative high capacity lithium-rich cathode oxides are discussed, attempting to understand the origins of the high lithium storage capacities of these materials. In addition, we provide perspectives for the further development of these lithium-rich cathode oxides based on multivalent cationic and anionic redox reactions, focusing on addressing the fundamental problems and promoting their practical applications.
