The global burden of bacterial infections,exacerbated by antimicrobial resistance(AMR),necessitates innovative strategies.Bacterial protein vaccines offer promise by eliciting targeted immunity while circumventing AMR...The global burden of bacterial infections,exacerbated by antimicrobial resistance(AMR),necessitates innovative strategies.Bacterial protein vaccines offer promise by eliciting targeted immunity while circumventing AMR.However,their clinical translation is hindered by their inherently low immunogenicity,often requiring potent adjuvants and advanced delivery systems.Biomembrane nanostructures(e.g.,liposomes,exosomes,and cell membrane-derived nanostructures),characterized by superior biocompatibility,intrinsic targeting ability,and immune-modulating properties,could serve as versatile platforms that potentiate vaccine efficacy by increasing antigen stability,enabling codelivery of immunostimulants,and facilitating targeted delivery to lymphoid tissues/antigen-presenting cells.This intrinsic immunomodulation promotes robust humoral and cellular immune responses to combat bacteria.This review critically reviews(1)key biomembrane nanostructure classes for bacterial protein antigens,(2)design strategies leveraging biomembrane nanostructures to enhance humoral and cellular immune responses,(3)preclinical efficacy against diverse pathogens,and(4)translational challenges and prospects.Biomembrane nanostructure-driven approaches represent a paradigm shift in the development of next-generation bacterial protein vaccines against resistant infections.展开更多
TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing Ti...TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance.展开更多
The dynamic behaviors of a large-scale ring neural network with a triangular coupling structure are investigated.The characteristic equation of the high-dimensional system using Coate’s flow graph method is calculate...The dynamic behaviors of a large-scale ring neural network with a triangular coupling structure are investigated.The characteristic equation of the high-dimensional system using Coate’s flow graph method is calculated.Time delay is selected as the bifurcation parameter,and sufficient conditions for stability and Hopf bifurcation are derived.It is found that the connection coefficient and time delay play a crucial role in the dynamic behaviors of the model.Furthermore,a phase diagram of multiple equilibrium points with one saddle point and two stable nodes is presented.Finally,the effectiveness of the theory is verified through simulation results.展开更多
The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties ...The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties of organic coatings.This study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over time.Coatings with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in real-time.Throughout the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy coating.The trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface analysis.This alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic coatings.Compared with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating.展开更多
Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,a...Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution.展开更多
Proton exchange membrane water electrolysis(PEMWE)is one of the most promising strategies to pro-duce green hydrogen energy,and it is crucial to exploit highly conductive and good corrosion-resistant coatings on bipol...Proton exchange membrane water electrolysis(PEMWE)is one of the most promising strategies to pro-duce green hydrogen energy,and it is crucial to exploit highly conductive and good corrosion-resistant coatings on bipolar plates(BPs),one of the core components in PEMWE cells.In this work,NbN coatings are deposited on Ti BPs by magnetron sputtering to improve the corrosion resistance and conductivity,for which the critical process parameters,such as the working pressure,partial nitrogen pressure and de-position temperature are well optimized.It is found that the compact microstructure,highly conductive δ-NbN and uniform nanoparticles play a dominant role in the synergistic improvement of the corrosion resistance and electrical conductivity of NbN coatings.The optimized NbN coatings exhibit excellent cor-rosion resistance with the low corrosion current density of 1.1×10^(-8) A cm^(-2),a high potential value of-0.005 V vs.SCE and a low ICR value of 15.8 mΩcm2@1.5 MPa.Accordingly,NbN coatings can be a promising candidate for the development of the low-cost and high-anti-corrosion Ti BPs of PEMWE.展开更多
Deep sea,with rich oil,gas,and mineral resources,plays an increasingly crucial role in scientific and industrial realms.However,the highly corrosive feature of deep sea hinders further exploration and development,whic...Deep sea,with rich oil,gas,and mineral resources,plays an increasingly crucial role in scientific and industrial realms.However,the highly corrosive feature of deep sea hinders further exploration and development,which requires metal materials with robust corrosion resistance.This review covers an in-depth and all-around overview of the up-to-date advances in corrosion and protection of metals in deep-sea environment.Firstly,the unique characteristics of deep-sea environment are summarized in detail.Subsequently,the corrosion performances of metals in both in situ and simulated deep-sea environments are illustrated systematically.Furthermore,corrosion prevent strategies of metals,including sacrificial anode protection,organic coatings,as well as coatings achieved by physical vapor deposition(PVD coatings),are highlighted.Finally,we outline current challenges and development trends of corrosion and protection of metals in deep-sea environment in the future.The purpose of this review is not only to summarize the recent progress on metal corrosion and protection in deep sea,but also to aid us in understanding them more comprehensively and deeply in a short time,so as to boost their fast development.展开更多
Sulfide-based all-solid-state lithium batteries(ASSLBs) with nickel-rich oxide cathodes are emerging as primary contenders for the next generation rechargeable batteries,owing to their superior safety and energy densi...Sulfide-based all-solid-state lithium batteries(ASSLBs) with nickel-rich oxide cathodes are emerging as primary contenders for the next generation rechargeable batteries,owing to their superior safety and energy density.However,the all-solid-state batteries with nickel-rich oxide cathodes suffer from performance degradation due to the reactions between the highly reactive surface oxygen of the cathode and the electrolyte,as well as the instability of the bulk oxygen structure in the cathode.Herein,we propose a synergistic modification design scheme to adjust the oxygen activity from surface to bulk.The LiBO_(2)coating inhibits the reactivity of surface lattice oxygen ions.Meanwhile,Zr doping in the bulk phase forms strong Zr-O covalent bonds that stabilize the bulk lattice oxygen structure.The synergistic effect of these modifications prevents the release of oxygen,thus avoiding the degradation of the cathode/SE interface.Additionally,the regulation of surface-to-bulk oxygen activity establishes a highly stable interface,thereby enhancing the lithium ion diffusion kinetics and mechanical stability of the cathode.Consequently,cathodes modified with this synergistic strategy exhibit outstanding performance in sulfide-based ASSLBs,including an ultra-long cycle life of 100,000 cycles,ultra-high rate capability at 45C,and 85% high active material content in the composite cathode.Additionally,ASSLB exhibits stable cycling under high loading conditions of 82.82 mg cm^(-2),achieving an areal capacity of 17.90 mA h cm^(-2).These encouraging results pave the way for practical applications of ASSLBs in fast charging,long cycle life,and high energy density in the future.展开更多
Nano-zinc oxides(ZnO)demonstrate remarkable antibacterial properties.To further enhance the corrosion resistance and antibacterial efficiency of magnesium alloy micro-arc oxidation(MAO)coatings,this study investigates...Nano-zinc oxides(ZnO)demonstrate remarkable antibacterial properties.To further enhance the corrosion resistance and antibacterial efficiency of magnesium alloy micro-arc oxidation(MAO)coatings,this study investigates the preparation of ZnO-containing micro-arc oxidation coatings with dual functionality by incorporating nano-ZnO into MAO electrolyte.The influence of varying ZnO concentrations on the microstructure,corrosion resistance,and antibacterial properties of the coating was examined through microstructure analysis,immersion tests,electrochemical experiments,and antibacterial assays.The findings revealed that the addition of nano-ZnO significantly enhanced the corrosion resistance of the MAO-coated alloy.Specifically,when the ZnO concentration in the electrolyte was 5 g/L,the corrosion rate was more than ten times lower compared to the MAO coatings without ZnO.Moreover,the antibacterial efficacy of ZnO+MAO coating,prepared with a ZnO concentration of 5 g/L,surpassed 95%after 24 h of co-culturing with Staphylococcus aureus(S.aureus).The nano-ZnO+MAO-coated alloy exhibited exceptional degradation resistance,corrosion resistance,and antibacterial effectiveness.展开更多
Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capac...Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capacity fading.Herein,the dual-strategy of Cr,B complex coating and local gradient doping is simultaneously achieved on LLO surface by a one-step wet chemical reaction at room temperature.Density functional theory(DFT)calculations prove that stable B-O and Cr-O bonds through the local gradient doping can significantly reduce the high-energy O 2p states of interfacial lattice O,which is also effective for the near-surface lattice O,thus greatly stabilizing the LLO surface,Besides,differential electrochemical mass spectrometry(DEMS)indicates that the Cr_(x)B complex coating can adequately inhibit oxygen release and prevents the migration or dissolution of transition metal ions,including allowing speedy Li^(+)migration,The voltage and capacity fading of the modified cathode(LLO-C_(r)B)are adequately suppressed,which are benefited from the uniformly dense cathode electrolyte interface(CEI)composed of balanced organic/inorganic composition.Therefore,the specific capacity of LLO-CrB after 200 cycles at 1C is 209.3 mA h g^(-1)(with a retention rate of 95.1%).This dual-strategy through a one-step wet chemical reaction is expected to be applied in the design and development of other anionic redox cathode materials.展开更多
Silicide coatings have proven to be promising for improving the high-temperature oxidation resistance of niobium alloy.However,the long-term protective property of single silicide coating remains a long-time endeavor ...Silicide coatings have proven to be promising for improving the high-temperature oxidation resistance of niobium alloy.However,the long-term protective property of single silicide coating remains a long-time endeavor due to the deficiency of oxygen-consuming phases,as well as the self-healing ability of the protective layer.Herein,a silicide-based composite coating is constructed on niobium alloy by incor-poration of nano-SiC particles for enhancing the high-temperature oxidation resistance.Isothermal oxi-dation results at 1250℃ for 50 h indicate that NbSi_(2)/Nb_(2)O_(5)-SiO_(2)/SiC multilayer coated sample with a low mass gain of 2.49 mg/cm^(2) shows an improved oxidation resistance compared with NbSi_(2) coating(6.49 mg/cm^(2)).The enhanced high-temperature antioxidant performance of NbSi_(2)/Nb_(2)O_(5)-SiO_(2)/SiC multi-layer coating is mainly attributed to the formation of the protective SiO_(2) self-healing film and the high-temperature diffusion behavior of NbSi_(2)/substrate.展开更多
基金the National Natural Science Foundation of China(82573571)the Shanghai 2025 Basic Research Plan Natural Science Foundation(25ZR1401393)the First Batch of Open Topics of the Shanghai Key Laboratory of Nautical Medicine and Translation of Drugs and Medical Devices(2025QN13)。
文摘The global burden of bacterial infections,exacerbated by antimicrobial resistance(AMR),necessitates innovative strategies.Bacterial protein vaccines offer promise by eliciting targeted immunity while circumventing AMR.However,their clinical translation is hindered by their inherently low immunogenicity,often requiring potent adjuvants and advanced delivery systems.Biomembrane nanostructures(e.g.,liposomes,exosomes,and cell membrane-derived nanostructures),characterized by superior biocompatibility,intrinsic targeting ability,and immune-modulating properties,could serve as versatile platforms that potentiate vaccine efficacy by increasing antigen stability,enabling codelivery of immunostimulants,and facilitating targeted delivery to lymphoid tissues/antigen-presenting cells.This intrinsic immunomodulation promotes robust humoral and cellular immune responses to combat bacteria.This review critically reviews(1)key biomembrane nanostructure classes for bacterial protein antigens,(2)design strategies leveraging biomembrane nanostructures to enhance humoral and cellular immune responses,(3)preclinical efficacy against diverse pathogens,and(4)translational challenges and prospects.Biomembrane nanostructure-driven approaches represent a paradigm shift in the development of next-generation bacterial protein vaccines against resistant infections.
基金supported by the Original Exploratory Program of the National Natural Science Foundation of China(No.52450012)。
文摘TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance.
基金Supported by Natural Science Foundation of Shandong Province of China(Grant Nos.ZR2020MF080 and ZR2020MF065).
文摘The dynamic behaviors of a large-scale ring neural network with a triangular coupling structure are investigated.The characteristic equation of the high-dimensional system using Coate’s flow graph method is calculated.Time delay is selected as the bifurcation parameter,and sufficient conditions for stability and Hopf bifurcation are derived.It is found that the connection coefficient and time delay play a crucial role in the dynamic behaviors of the model.Furthermore,a phase diagram of multiple equilibrium points with one saddle point and two stable nodes is presented.Finally,the effectiveness of the theory is verified through simulation results.
基金financially supported by the National Natural Science Foundation of China(No.52371049)the Young Elite Scientists Sponsorship Program by the China Association for Science and Technology(YESS,No.2020QNRC001)the National Science and Technology Resources Investigation Program of China(Nos.2021FY100603 and 2019FY101404)。
文摘The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties of organic coatings.This study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over time.Coatings with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in real-time.Throughout the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy coating.The trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface analysis.This alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic coatings.Compared with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating.
基金National Natural Science Foundation of China(52071126)Natural Science Foundation of Tianjin City,China(22JCQNJC01240)+2 种基金Central Guidance on Local Science and Technology Development Fund of Hebei Province(226Z1009G)Special Funds for Science and Technology Innovation in Hebei(2022X19)Anhui Provincial Natural Science Foundation(2308085ME135)。
文摘Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution.
基金supported by the National Key Re-search and Development Program of China(No.2022YFB4002100)the National Natural Science Foundation of China(No.52271136)the Natural Science Foundation of Shaanxi Province(Nos.2019TD-020 and 2021JC-06).
文摘Proton exchange membrane water electrolysis(PEMWE)is one of the most promising strategies to pro-duce green hydrogen energy,and it is crucial to exploit highly conductive and good corrosion-resistant coatings on bipolar plates(BPs),one of the core components in PEMWE cells.In this work,NbN coatings are deposited on Ti BPs by magnetron sputtering to improve the corrosion resistance and conductivity,for which the critical process parameters,such as the working pressure,partial nitrogen pressure and de-position temperature are well optimized.It is found that the compact microstructure,highly conductive δ-NbN and uniform nanoparticles play a dominant role in the synergistic improvement of the corrosion resistance and electrical conductivity of NbN coatings.The optimized NbN coatings exhibit excellent cor-rosion resistance with the low corrosion current density of 1.1×10^(-8) A cm^(-2),a high potential value of-0.005 V vs.SCE and a low ICR value of 15.8 mΩcm2@1.5 MPa.Accordingly,NbN coatings can be a promising candidate for the development of the low-cost and high-anti-corrosion Ti BPs of PEMWE.
基金the National Key R&D Program of China(No.2022YFB3808800)the National Natural Science Foundation of China(Nos.52301406 and 52375219)+2 种基金the Natural Science Foundation of Zhejiang Province(No.LR21E050001)the China Postdoctoral Science Foundation(No.2023M733600)the Ningbo Natural Science Foundation(No.2023J329).
文摘Deep sea,with rich oil,gas,and mineral resources,plays an increasingly crucial role in scientific and industrial realms.However,the highly corrosive feature of deep sea hinders further exploration and development,which requires metal materials with robust corrosion resistance.This review covers an in-depth and all-around overview of the up-to-date advances in corrosion and protection of metals in deep-sea environment.Firstly,the unique characteristics of deep-sea environment are summarized in detail.Subsequently,the corrosion performances of metals in both in situ and simulated deep-sea environments are illustrated systematically.Furthermore,corrosion prevent strategies of metals,including sacrificial anode protection,organic coatings,as well as coatings achieved by physical vapor deposition(PVD coatings),are highlighted.Finally,we outline current challenges and development trends of corrosion and protection of metals in deep-sea environment in the future.The purpose of this review is not only to summarize the recent progress on metal corrosion and protection in deep sea,but also to aid us in understanding them more comprehensively and deeply in a short time,so as to boost their fast development.
基金financially supported by the National Natural Science Foundation of China (52474338,22109084 and 52304338)the Hunan Provincial Key Research and Development Program (2024JK2093,2023GK2016)supported in part by the High Performance Computing Center of Central South University.
文摘Sulfide-based all-solid-state lithium batteries(ASSLBs) with nickel-rich oxide cathodes are emerging as primary contenders for the next generation rechargeable batteries,owing to their superior safety and energy density.However,the all-solid-state batteries with nickel-rich oxide cathodes suffer from performance degradation due to the reactions between the highly reactive surface oxygen of the cathode and the electrolyte,as well as the instability of the bulk oxygen structure in the cathode.Herein,we propose a synergistic modification design scheme to adjust the oxygen activity from surface to bulk.The LiBO_(2)coating inhibits the reactivity of surface lattice oxygen ions.Meanwhile,Zr doping in the bulk phase forms strong Zr-O covalent bonds that stabilize the bulk lattice oxygen structure.The synergistic effect of these modifications prevents the release of oxygen,thus avoiding the degradation of the cathode/SE interface.Additionally,the regulation of surface-to-bulk oxygen activity establishes a highly stable interface,thereby enhancing the lithium ion diffusion kinetics and mechanical stability of the cathode.Consequently,cathodes modified with this synergistic strategy exhibit outstanding performance in sulfide-based ASSLBs,including an ultra-long cycle life of 100,000 cycles,ultra-high rate capability at 45C,and 85% high active material content in the composite cathode.Additionally,ASSLB exhibits stable cycling under high loading conditions of 82.82 mg cm^(-2),achieving an areal capacity of 17.90 mA h cm^(-2).These encouraging results pave the way for practical applications of ASSLBs in fast charging,long cycle life,and high energy density in the future.
基金supported by the National Natural Science Foundation of China(No.52001034)the China Postdoctoral Science Foundation(No.2023M731677)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX23_3032).
文摘Nano-zinc oxides(ZnO)demonstrate remarkable antibacterial properties.To further enhance the corrosion resistance and antibacterial efficiency of magnesium alloy micro-arc oxidation(MAO)coatings,this study investigates the preparation of ZnO-containing micro-arc oxidation coatings with dual functionality by incorporating nano-ZnO into MAO electrolyte.The influence of varying ZnO concentrations on the microstructure,corrosion resistance,and antibacterial properties of the coating was examined through microstructure analysis,immersion tests,electrochemical experiments,and antibacterial assays.The findings revealed that the addition of nano-ZnO significantly enhanced the corrosion resistance of the MAO-coated alloy.Specifically,when the ZnO concentration in the electrolyte was 5 g/L,the corrosion rate was more than ten times lower compared to the MAO coatings without ZnO.Moreover,the antibacterial efficacy of ZnO+MAO coating,prepared with a ZnO concentration of 5 g/L,surpassed 95%after 24 h of co-culturing with Staphylococcus aureus(S.aureus).The nano-ZnO+MAO-coated alloy exhibited exceptional degradation resistance,corrosion resistance,and antibacterial effectiveness.
基金financially supported by the National Natural Science Foundation of China(No.12304077)the Natural Science Foundation of Science and Technology Department of Sichuan Province(No.23NSFSC6224)+3 种基金Sichuan Science and Technology Program(No.2024NSFSC0989)the Key Laboratory of Computational Physics of Sichuan Province(No.YBUJSWL-YB-2022-03)the Material Corrosion and Protection Key Laboratory of Sichuan Province(No.2023CL14 and No.2023CL01)the National Innovation Practice Project(No.202411079005S).
文摘Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capacity fading.Herein,the dual-strategy of Cr,B complex coating and local gradient doping is simultaneously achieved on LLO surface by a one-step wet chemical reaction at room temperature.Density functional theory(DFT)calculations prove that stable B-O and Cr-O bonds through the local gradient doping can significantly reduce the high-energy O 2p states of interfacial lattice O,which is also effective for the near-surface lattice O,thus greatly stabilizing the LLO surface,Besides,differential electrochemical mass spectrometry(DEMS)indicates that the Cr_(x)B complex coating can adequately inhibit oxygen release and prevents the migration or dissolution of transition metal ions,including allowing speedy Li^(+)migration,The voltage and capacity fading of the modified cathode(LLO-C_(r)B)are adequately suppressed,which are benefited from the uniformly dense cathode electrolyte interface(CEI)composed of balanced organic/inorganic composition.Therefore,the specific capacity of LLO-CrB after 200 cycles at 1C is 209.3 mA h g^(-1)(with a retention rate of 95.1%).This dual-strategy through a one-step wet chemical reaction is expected to be applied in the design and development of other anionic redox cathode materials.
基金supported by the National Natural Science Foundation of China(Nos.U21B2053,52071114,52001100,and 523B2010)Outstanding Youth Project of Natural Science Foundation of Heilongjiang Province(No.YQ2023E008)+1 种基金Young Elite Scientists Sponsorship Program by CAST(NO.2021QNRC001)Heilongjiang Touyan Team Program.
文摘Silicide coatings have proven to be promising for improving the high-temperature oxidation resistance of niobium alloy.However,the long-term protective property of single silicide coating remains a long-time endeavor due to the deficiency of oxygen-consuming phases,as well as the self-healing ability of the protective layer.Herein,a silicide-based composite coating is constructed on niobium alloy by incor-poration of nano-SiC particles for enhancing the high-temperature oxidation resistance.Isothermal oxi-dation results at 1250℃ for 50 h indicate that NbSi_(2)/Nb_(2)O_(5)-SiO_(2)/SiC multilayer coated sample with a low mass gain of 2.49 mg/cm^(2) shows an improved oxidation resistance compared with NbSi_(2) coating(6.49 mg/cm^(2)).The enhanced high-temperature antioxidant performance of NbSi_(2)/Nb_(2)O_(5)-SiO_(2)/SiC multi-layer coating is mainly attributed to the formation of the protective SiO_(2) self-healing film and the high-temperature diffusion behavior of NbSi_(2)/substrate.
