Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challeng...Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challenges such as structural phase transitions,Na^(+)/vacancy ordering,and Jahn–Teller distortion effect,resulting in severe capacity decay and sluggish ion kinetics.We develop a novel Cu/Y dual-doping strategy that leads to the formation of"Na–Y"interlayer aggregates,which act as structural pillars within alkali metal layers,enhancing structural stability and disrupting the ordered arrangement of Na^(+)/vacancies.This disruption leads to a unique coexistence of ordered and disordered Na^(+)/vacancy states with near-zero strain,which significantly improves Na^(+)diffusion kinetics.This structural innovation not only mitigates the unfavorable P2–O2 phase transition but also facilitates rapid ion transport.As a result,the doped material demonstrates exceptional electrochemical performance,including an ultra-long cycle life of 3000 cycles at 10 C and an outstanding high-rate capability of~70 mAh g^(−1)at 50 C.The discovery of this novel interlayer pillar,along with its role in modulating Na^(+)/vacancy arrangements,provides a fresh perspective on engineering layered oxides.It opens up promising new pathways for the structural design of advanced cathode materials toward efficient,stable,and high-rate SIBs.展开更多
High-capacity O3-type layered NiFeMn-based oxides are promising cathodes for sodium-ion batteries,though their practical deployment is constrained by the inherent limitations of Fe redox chemistry.Traditional designs ...High-capacity O3-type layered NiFeMn-based oxides are promising cathodes for sodium-ion batteries,though their practical deployment is constrained by the inherent limitations of Fe redox chemistry.Traditional designs generally enforcing stoichiometric symmetry(Ni=Mn)yield low Fe redox activity.Herein,we propose a valence engineering strategy that breaks conventional Ni/Mn stoichiometry to reconfigure Fe's local chemical environment and unlock unprecedented redox depth.Density functional theory(DFT)calculations reveal that the designed NaNi_(0.35)Fe_(0.225)Mn_(0.425)O_(2)cathode exhibits a reduced Bader charge on Fe(1.598 vs.1.638 in NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2))and elevated Fe 3d orbital energy,signifying enhanced Fe redox activity.This configuration enables an exceptional Fe^(2.60+)/Fe^(3.88+)redox(1.28 e~-per Fe),delivering a reversible capacity of184.3 mAh g^(-1)within 2-4.2 V at 0.2 C,markedly exceeding the benchmark NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(161.3 mAh g^(-1))with low reaction depth of Fe^(3.01+)/Fe^(3.61+).The intensified cationic redox reaction enables an ultrahigh energy density of 596 Whkg-1.The NaNi_(0.35)Fe_(0.225)Mn_(0.425)O_(2)cathode demonstrates robust performance over a broad temperature range from-15℃to 60℃.In situ and ex situ characterizations unveil a reversible O3■P3■OP2 phase transition with minimal volume change(1.88%)that circumvents detrimental deleterious O'3 intermediates and intragranular cracking.This work establishes valence engineering as a paradigm to consolidate cationic redox reaction in high-energy layered sodium oxide cathodes.展开更多
The use of Cu_(2)O-based photocathodes has demonstrated the promising activity of these earth-abundant materials for the photoelectrochemical CO_(2)reduction reaction(CO_(2)RR),particularly in producing methanol.Howev...The use of Cu_(2)O-based photocathodes has demonstrated the promising activity of these earth-abundant materials for the photoelectrochemical CO_(2)reduction reaction(CO_(2)RR),particularly in producing methanol.However,their application in long-term devices is hindered by severe photocorrosion.To address this limitation,photocathode designs incorporating Schottky barriers,heterojunctions,and scaffolding layers have been explored.In this work,a CuBi_(2)O_(4)/CuO thin layer was employed as a scaffold to support Cu_(2)O films with either seeded or grown morphologies for enhanced photoelectrochemical CO_(2)RR.Photoelectrochemical testing in CO_(2)-saturated electrolyte revealed that 0.55 V vs.reversible hydrogen electrode(RHE)yielded the highest activity and stability for methanol(CH_(3)OH)production,outperforming more negative potentials.Furthermore,the present work highlighted that electrolyte engineering can be used to promote the generation of alternative products such as methyl acetate(CH_(3)COOCH_(3)).The presence of CuBi_(2)O_(4)/CuO scaffold was critical for allowing this pathway,providing both enhanced stability and improved charge transfer on the Cu_(2)O surface.The generation of CH_(3)COOCH_(3)is attributed to locally modified microenvironments that facilitate the esterification reaction when acetate is present in solution.These findings highlight the role of scaffold engineering in improving photocathode performance and electrolyte tuning in steering product selectivity toward scarcely explored,added-value compounds such as methyl acetate.展开更多
Vanadium-based materials have emerged as promising cathode candidates for aqueous zinc-ion batteries(AZIBs)due to their multivalent redox characteristics and diverse crystal structures,which enable high energy storage...Vanadium-based materials have emerged as promising cathode candidates for aqueous zinc-ion batteries(AZIBs)due to their multivalent redox characteristics and diverse crystal structures,which enable high energy storage capacity.Nevertheless,practical applications are hindered by several critical challenges,including vanadium species dissolution,side-product formation,sluggish Zn^(2+)diffusion kinetics,and low electrical conductivity.Organic functionalization,benefiting from its structural tunability and abundant functional groups,has been proven to be an effective strategy for enhancing the electrochemical performance of vanadium-based cathodes.This review systematically summarizes recent advances in organic-functionalized vanadium-based cathodes.First,the energy storage mechanism of vanadiumbased cathodes and the fundamental properties of organic compounds relevant to cathode optimization are outlined.Then,the functions of organic compounds are comprehensively analyzed from four key perspectives:capacity improvement,conductivity enhancement,Zn^(2+)diffusion kinetics optimization,and cycling stability promotion.Furthermore,the specific electrochemical performance modulation effects and practical application examples of this strategy are discussed in detail.Finally,current limitations and challenges in this field are highlighted,and corresponding solutions and future research directions are proposed,offering theoretical guidance and insights for the development of high-performance vanadium-based cathodes for AZIBs.展开更多
Zinc-iodine(Zn-I_(2))batteries are deemed as potential candidate of energy storage system for the merits of high safety,cost-effectiveness,high capacity,and environmental compatibility.Unfortunately,the practical impl...Zinc-iodine(Zn-I_(2))batteries are deemed as potential candidate of energy storage system for the merits of high safety,cost-effectiveness,high capacity,and environmental compatibility.Unfortunately,the practical implementation of Zn-I_(2)batteries is still hindered by the sluggish iodine redox kinetics and the shuttle effect of soluble polyiodides,which induce rapid capacity decay and electrode interface passivation.This work proposes platinum/carbon(Pt/C)and iridium/carbon(Ir/C)composite as conductive catalytic iodine hosts,which realizes the physical confinement for active iodine through the intrinsic porous structure.The introduction of active Pt/Ir sites effectively anchors the polyiodides through chemical adsorption capability,and inhibits shuttle effect and Zn metal corrosion.In addition,the superior electrical conductivity and catalytic activity of Pt/C and Ir/C carriers also contribute to reduce the reaction energy barriers,significantly promoting the electrochemical performance and conversion reaction kinetics.As expected,the assembled Zn//Pt/C@I_(2)and Zn//Ir/C@I_(2)batteries achieve impressive reversible capacity of 132.2 and 108 mAh g^(-1)after 2000 cycles at 200 mA g^(-1),respectively,and their capacity retention rate after 25000 cycles at 1000 mA g^(-1)are as high as 88.1%and 85.9%.This study will guide the carrier design of iodine cathode to drive the application of high-performance Zn-I2batteries.展开更多
Complex phase transitions occur in P2-type materials during charging and discharging.A high-entropy structure can effectively inhibit the structural phase transition of a P2-type layered material.In this study,a hight...Complex phase transitions occur in P2-type materials during charging and discharging.A high-entropy structure can effectively inhibit the structural phase transition of a P2-type layered material.In this study,a hightemperature solid-phase method is used to synthesize the P2-type high-entropy fluorine oxide(HEFO)Na_(0.7)Li_(0.08)Mn(Ⅳ)_(0.21)Mn(Ⅲ)_(0.43)Mg_(0.11)Ni_(0.11)W_(0.04)Nb_(0.02)O_(1.9)F_(0.1)[■-NLM(Ⅳ)0.21M(Ⅲ)0.43F(■=NMNWO)],with a superlattice structure and Na_(2)WO_(4)coating.Na_(2)WO_(4)can effectively inhibit the complex phase transition to improve the structural stability of the material and overcome the limitations of P2-type Na_(x)TMO_(2)(TM=transition metal)via additional charge compensation.Adjusting the Mn^(3+)/Mn^(4+)ratio to increase the average valence state of Mn and introducing F^(-)and Li^(+)to inhibit the Jahn-Teller effect suppress the complex phase transition during charging and discharging.The material exhibits a good multiplicative performance(discharge specific capacity of 88.4 mAh g^(-1)at a multiplicative rate of 10C)and capacity retention(99.22%after 200 cycles at 1C in the potential window of 1.5-4.3 V).The structural stabilities of HEFO are effectively demonstrated using electrochemical in situ X-ray diffraction and ex situ X-ray photoelectron spectroscopy.Theoretical calculations reveal that the high-entropy structure effectively improves the electronic structure and charge distribution of the layered oxide material.This study provides new concepts for use in developing novel energy batteries.展开更多
Potassium-ion batteries(PIBs)were recognized for their natural abunda nce,high theoretical output voltage,and the availability of commercialized graphite anodes.However,the development of highperformance manganese-bas...Potassium-ion batteries(PIBs)were recognized for their natural abunda nce,high theoretical output voltage,and the availability of commercialized graphite anodes.However,the development of highperformance manganese-based layered oxide cathodes-a leading candidate for PIB systems-has been fundamentally constrained by irreversible phase transitions(PT)during the cycling process,manifesting as severe structural degradation and capacity fading.This review presents a transformative paradigm integrating machine learning(ML)with multiscale characterization to analyse the complex phase transition mechanisms in Mn-based cathodes.Through systematic ML-driven interrogation of structure-property relationships,we establish quantitative descriptors for phase stability and develop predictive models for transition dynamics.Furthermore,we highlight recent breakthroughs in cross-disciplinary approaches,enabling the rational design of PT-mitigated cathode architectures.By consolidating these insights into a unified knowledge framework,this work provides strategic guidelines for developing structurally robust Mn-based cathodes and outlines future research directions for next-generation PIB systems.展开更多
Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical b...Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical behaviors,yet has not been unraveled.Here we propose an NH_(4)^(+)-modulated cationic solvation strategy to optimize cathodic spatial charge distribution and achieve dynamic Zn^(2+)/NH_(4)^(+)co-storage for boosting Zinc hybrid capacitors.Owing to the hierarchical cationic solvated structure in hybrid Zn(CF_(3)SO_(3))_(2)–NH_4CF_(3)SO_(3)electrolyte,high-reactive Zn^(2+)and small-hydrate-sized NH_4(H_(2)O))(4)^(+)induce cathodic interfacial Helmholtz plane reconfiguration,thus effectively enhancing the spatial charge density to activate 20%capacity enhancement.Furthermore,cathodic interfacial adsorbed hydrated NH_(4)^(+)ions afford high-kinetics and ultrastable C···H(NH_(4)^(+))charge storage process due to a much lower desolvation energy barrier compared with heavy and rigid Zn(H_(2)O)_6^(2+)(5.81 vs.14.90 eV).Consequently,physical uptake and multielectron redox of Zn^(2+)/NH_(4)^(+)in carbon cathode enable the zinc capacitor to deliver high capacity(240 mAh g^(-1)at 0.5 A g^(-1)),large-current tolerance(130 mAh g^(-1)at 50 A g^(-1))and ultralong lifespan(400,000cycles).This study gives new insights into the design of cathode–electrolyte interfaces toward advanced zinc-based energy storage.展开更多
Minimizing the thermal expansion coefficient(TEC)mismatch between the cathode and electrolyte in solid oxide fuel cells is crucial for achieving stable,durable operation and high performance.Recently,materials with ne...Minimizing the thermal expansion coefficient(TEC)mismatch between the cathode and electrolyte in solid oxide fuel cells is crucial for achieving stable,durable operation and high performance.Recently,materials with negative thermal expansion(NTE)have at-tracted significant attention as effective additives for tailoring the thermomechanical properties of electrodes and enhancing cell durability.In this work,for the first time,single-phase NTE perovskite Sm_(0.85)Zn_(0.15)MnO_(3−δ)(SZM15)was successfully synthesized via the sol-gel method,eliminating the unwanted ZnO phase typically observed in materials obtained through the conventional solid-state reaction route.The sol-gel approach proved highly advantageous,offering low cost,robustness,excellent chemical homogeneity,precise compositional control,and high phase purity.After optimization of synthesis parameters,a negative TEC of approximately−6.5×10^(−6)K^(−1)was achieved in the 400-850℃range.SZM15 was then incorporated as an additive(10wt%-50wt%)into a SmBa0.5Sr0.5CoCuO_(5+δ)(SBSCCO)cathode to tune the thermomechanical properties with a La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(0.2)O_(3−δ)(LSGM)electrolyte,achieving a minimal TEC mismatch of only 1%.Notably,the SBSCCO+10wt%SZM15 composite cathode exhibited the lowest polarization resistance of 0.019Ω·cm^(2)at 900℃,showing approximately 70%lower than that of the pristine cathode.Excellent long-term stability after 100 h of operation was achieved.In addition,a high peak power density of 680 mW·cm^(−2)was achieved in a Ni-YSZ(yttria-stabilized zirconia)|YSZ|Ce_(0.9)Gd_(0.1)O_(2−δ)(GDC10)|SBSCCO+10wt%SZM15 anode-supported fuel cell at 850℃,highlighting the effectiveness of incorporating NTE materials as a promising strategy for regulating the thermomechanical properties and improving the long-term stability of intermediate temperature solid oxide fuel cells(IT-SOFCs).展开更多
基金supported by the “Pioneer” and “Leading Goose” R&D Program of Zhejiang Province of China (No. 2024C01056)the support from London South Bank University
文摘Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challenges such as structural phase transitions,Na^(+)/vacancy ordering,and Jahn–Teller distortion effect,resulting in severe capacity decay and sluggish ion kinetics.We develop a novel Cu/Y dual-doping strategy that leads to the formation of"Na–Y"interlayer aggregates,which act as structural pillars within alkali metal layers,enhancing structural stability and disrupting the ordered arrangement of Na^(+)/vacancies.This disruption leads to a unique coexistence of ordered and disordered Na^(+)/vacancy states with near-zero strain,which significantly improves Na^(+)diffusion kinetics.This structural innovation not only mitigates the unfavorable P2–O2 phase transition but also facilitates rapid ion transport.As a result,the doped material demonstrates exceptional electrochemical performance,including an ultra-long cycle life of 3000 cycles at 10 C and an outstanding high-rate capability of~70 mAh g^(−1)at 50 C.The discovery of this novel interlayer pillar,along with its role in modulating Na^(+)/vacancy arrangements,provides a fresh perspective on engineering layered oxides.It opens up promising new pathways for the structural design of advanced cathode materials toward efficient,stable,and high-rate SIBs.
基金supported by the National Natural Science Foundation of China(Grant Nos.52202282,52402054,22471283,and 52202327)Natural Science Foundation of Tianjin City(Grant Nos.22JCYBJC00040,24JCQNJC00970)。
文摘High-capacity O3-type layered NiFeMn-based oxides are promising cathodes for sodium-ion batteries,though their practical deployment is constrained by the inherent limitations of Fe redox chemistry.Traditional designs generally enforcing stoichiometric symmetry(Ni=Mn)yield low Fe redox activity.Herein,we propose a valence engineering strategy that breaks conventional Ni/Mn stoichiometry to reconfigure Fe's local chemical environment and unlock unprecedented redox depth.Density functional theory(DFT)calculations reveal that the designed NaNi_(0.35)Fe_(0.225)Mn_(0.425)O_(2)cathode exhibits a reduced Bader charge on Fe(1.598 vs.1.638 in NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2))and elevated Fe 3d orbital energy,signifying enhanced Fe redox activity.This configuration enables an exceptional Fe^(2.60+)/Fe^(3.88+)redox(1.28 e~-per Fe),delivering a reversible capacity of184.3 mAh g^(-1)within 2-4.2 V at 0.2 C,markedly exceeding the benchmark NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(161.3 mAh g^(-1))with low reaction depth of Fe^(3.01+)/Fe^(3.61+).The intensified cationic redox reaction enables an ultrahigh energy density of 596 Whkg-1.The NaNi_(0.35)Fe_(0.225)Mn_(0.425)O_(2)cathode demonstrates robust performance over a broad temperature range from-15℃to 60℃.In situ and ex situ characterizations unveil a reversible O3■P3■OP2 phase transition with minimal volume change(1.88%)that circumvents detrimental deleterious O'3 intermediates and intragranular cracking.This work establishes valence engineering as a paradigm to consolidate cationic redox reaction in high-energy layered sodium oxide cathodes.
基金funding support from the INCT-DATREM:FAPESP:2014/50945-4,CNPq|:465571/2014-0,and Capes:88887136426/2017/10Programa Nacional de Investigación Científica y Estudios Avanzados(PROCIENCIA)with grant number 237-2015-FONDECYT+2 种基金We thank the support from Vicerrectorado de Investigación(VRI-UNI).Serrapilheira Institute[Grant number Serra–2211-41925]São Paulo Research Foundation,FAPESP[Grant number#2023/10027-5][Grant numbers#406156/2022-0,180111/2023-0]。
文摘The use of Cu_(2)O-based photocathodes has demonstrated the promising activity of these earth-abundant materials for the photoelectrochemical CO_(2)reduction reaction(CO_(2)RR),particularly in producing methanol.However,their application in long-term devices is hindered by severe photocorrosion.To address this limitation,photocathode designs incorporating Schottky barriers,heterojunctions,and scaffolding layers have been explored.In this work,a CuBi_(2)O_(4)/CuO thin layer was employed as a scaffold to support Cu_(2)O films with either seeded or grown morphologies for enhanced photoelectrochemical CO_(2)RR.Photoelectrochemical testing in CO_(2)-saturated electrolyte revealed that 0.55 V vs.reversible hydrogen electrode(RHE)yielded the highest activity and stability for methanol(CH_(3)OH)production,outperforming more negative potentials.Furthermore,the present work highlighted that electrolyte engineering can be used to promote the generation of alternative products such as methyl acetate(CH_(3)COOCH_(3)).The presence of CuBi_(2)O_(4)/CuO scaffold was critical for allowing this pathway,providing both enhanced stability and improved charge transfer on the Cu_(2)O surface.The generation of CH_(3)COOCH_(3)is attributed to locally modified microenvironments that facilitate the esterification reaction when acetate is present in solution.These findings highlight the role of scaffold engineering in improving photocathode performance and electrolyte tuning in steering product selectivity toward scarcely explored,added-value compounds such as methyl acetate.
基金financial support from the National Natural Science Foundation of China(No.21676036)the Natural Science Foundation of Chongqing(No.CSTB2023NSCQMSX0580)the Large-scale Equipment Sharing Fund of Chongqing University(No.202403150240 and 202503150091)。
文摘Vanadium-based materials have emerged as promising cathode candidates for aqueous zinc-ion batteries(AZIBs)due to their multivalent redox characteristics and diverse crystal structures,which enable high energy storage capacity.Nevertheless,practical applications are hindered by several critical challenges,including vanadium species dissolution,side-product formation,sluggish Zn^(2+)diffusion kinetics,and low electrical conductivity.Organic functionalization,benefiting from its structural tunability and abundant functional groups,has been proven to be an effective strategy for enhancing the electrochemical performance of vanadium-based cathodes.This review systematically summarizes recent advances in organic-functionalized vanadium-based cathodes.First,the energy storage mechanism of vanadiumbased cathodes and the fundamental properties of organic compounds relevant to cathode optimization are outlined.Then,the functions of organic compounds are comprehensively analyzed from four key perspectives:capacity improvement,conductivity enhancement,Zn^(2+)diffusion kinetics optimization,and cycling stability promotion.Furthermore,the specific electrochemical performance modulation effects and practical application examples of this strategy are discussed in detail.Finally,current limitations and challenges in this field are highlighted,and corresponding solutions and future research directions are proposed,offering theoretical guidance and insights for the development of high-performance vanadium-based cathodes for AZIBs.
基金the National Natural Science Foundation of China(Nos.52404316,52461040,52274297,52474325,and 22202053)Hainan Provincial Natural Science Foundation(No.524RC475)+3 种基金Collaborative Innovation Center of Marine Science and Technology of Hainan University(No.XTCX2022HYC14)Start-up Research Foundation of Hainan University(Nos.XJ2400012968,KYQD(ZR)23069,23169 and 21124the support for comprehensive characterizations by Pico Election Microscopy Center of Hainan Universitythe funding supports from China Scholarship Council。
文摘Zinc-iodine(Zn-I_(2))batteries are deemed as potential candidate of energy storage system for the merits of high safety,cost-effectiveness,high capacity,and environmental compatibility.Unfortunately,the practical implementation of Zn-I_(2)batteries is still hindered by the sluggish iodine redox kinetics and the shuttle effect of soluble polyiodides,which induce rapid capacity decay and electrode interface passivation.This work proposes platinum/carbon(Pt/C)and iridium/carbon(Ir/C)composite as conductive catalytic iodine hosts,which realizes the physical confinement for active iodine through the intrinsic porous structure.The introduction of active Pt/Ir sites effectively anchors the polyiodides through chemical adsorption capability,and inhibits shuttle effect and Zn metal corrosion.In addition,the superior electrical conductivity and catalytic activity of Pt/C and Ir/C carriers also contribute to reduce the reaction energy barriers,significantly promoting the electrochemical performance and conversion reaction kinetics.As expected,the assembled Zn//Pt/C@I_(2)and Zn//Ir/C@I_(2)batteries achieve impressive reversible capacity of 132.2 and 108 mAh g^(-1)after 2000 cycles at 200 mA g^(-1),respectively,and their capacity retention rate after 25000 cycles at 1000 mA g^(-1)are as high as 88.1%and 85.9%.This study will guide the carrier design of iodine cathode to drive the application of high-performance Zn-I2batteries.
基金financially supported by the Guizhou Provincial Basic Research Program(Natural Science)(No.QKHJC-ZK[2023]YB051)the Natural Science Special Foundation of Guizhou University(No.GDTGH[2022]33)+2 种基金the Natural Science Research project of the Education Department of Guizhou Province(No.QJJ[2022]001)the National Natural Science Foundation of China(No.52161029)the Science and Technology Innovation Team of Education Agency in Guizhou Province(No.Qian Jiao Ji[2023]056)
文摘Complex phase transitions occur in P2-type materials during charging and discharging.A high-entropy structure can effectively inhibit the structural phase transition of a P2-type layered material.In this study,a hightemperature solid-phase method is used to synthesize the P2-type high-entropy fluorine oxide(HEFO)Na_(0.7)Li_(0.08)Mn(Ⅳ)_(0.21)Mn(Ⅲ)_(0.43)Mg_(0.11)Ni_(0.11)W_(0.04)Nb_(0.02)O_(1.9)F_(0.1)[■-NLM(Ⅳ)0.21M(Ⅲ)0.43F(■=NMNWO)],with a superlattice structure and Na_(2)WO_(4)coating.Na_(2)WO_(4)can effectively inhibit the complex phase transition to improve the structural stability of the material and overcome the limitations of P2-type Na_(x)TMO_(2)(TM=transition metal)via additional charge compensation.Adjusting the Mn^(3+)/Mn^(4+)ratio to increase the average valence state of Mn and introducing F^(-)and Li^(+)to inhibit the Jahn-Teller effect suppress the complex phase transition during charging and discharging.The material exhibits a good multiplicative performance(discharge specific capacity of 88.4 mAh g^(-1)at a multiplicative rate of 10C)and capacity retention(99.22%after 200 cycles at 1C in the potential window of 1.5-4.3 V).The structural stabilities of HEFO are effectively demonstrated using electrochemical in situ X-ray diffraction and ex situ X-ray photoelectron spectroscopy.Theoretical calculations reveal that the high-entropy structure effectively improves the electronic structure and charge distribution of the layered oxide material.This study provides new concepts for use in developing novel energy batteries.
基金financially supported by the National Natural Science Foundation of China(U20A20247)the National Key Research and Development Program of the Ministry of Science and Technology(2022YFA1402504)+1 种基金Guangdong Provincial Key Laboratory of Materials and Technologies for Energy Conversion(MATEC2023KF002)Guangdong Science and Technology Department(STKJ2021016)。
文摘Potassium-ion batteries(PIBs)were recognized for their natural abunda nce,high theoretical output voltage,and the availability of commercialized graphite anodes.However,the development of highperformance manganese-based layered oxide cathodes-a leading candidate for PIB systems-has been fundamentally constrained by irreversible phase transitions(PT)during the cycling process,manifesting as severe structural degradation and capacity fading.This review presents a transformative paradigm integrating machine learning(ML)with multiscale characterization to analyse the complex phase transition mechanisms in Mn-based cathodes.Through systematic ML-driven interrogation of structure-property relationships,we establish quantitative descriptors for phase stability and develop predictive models for transition dynamics.Furthermore,we highlight recent breakthroughs in cross-disciplinary approaches,enabling the rational design of PT-mitigated cathode architectures.By consolidating these insights into a unified knowledge framework,this work provides strategic guidelines for developing structurally robust Mn-based cathodes and outlines future research directions for next-generation PIB systems.
基金financially supported by the National Natural Science Foundation of China(Nos.22272118,22172111 and 22309134)the Science and Technology Commission of Shanghai Municipality,China(Nos.22ZR1464100,20ZR1460300 and 19DZ2271500)+3 种基金China Postdoctoral Science Foundation(2022M712402)Shanghai Rising-Star Program(23YF1449200)Zhejiang Provincial Science and Technology Project(2022C01182)the Fundamental Research Funds for the Central Universities(22120210529 and 2023-3-YB-07)。
文摘Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical behaviors,yet has not been unraveled.Here we propose an NH_(4)^(+)-modulated cationic solvation strategy to optimize cathodic spatial charge distribution and achieve dynamic Zn^(2+)/NH_(4)^(+)co-storage for boosting Zinc hybrid capacitors.Owing to the hierarchical cationic solvated structure in hybrid Zn(CF_(3)SO_(3))_(2)–NH_4CF_(3)SO_(3)electrolyte,high-reactive Zn^(2+)and small-hydrate-sized NH_4(H_(2)O))(4)^(+)induce cathodic interfacial Helmholtz plane reconfiguration,thus effectively enhancing the spatial charge density to activate 20%capacity enhancement.Furthermore,cathodic interfacial adsorbed hydrated NH_(4)^(+)ions afford high-kinetics and ultrastable C···H(NH_(4)^(+))charge storage process due to a much lower desolvation energy barrier compared with heavy and rigid Zn(H_(2)O)_6^(2+)(5.81 vs.14.90 eV).Consequently,physical uptake and multielectron redox of Zn^(2+)/NH_(4)^(+)in carbon cathode enable the zinc capacitor to deliver high capacity(240 mAh g^(-1)at 0.5 A g^(-1)),large-current tolerance(130 mAh g^(-1)at 50 A g^(-1))and ultralong lifespan(400,000cycles).This study gives new insights into the design of cathode–electrolyte interfaces toward advanced zinc-based energy storage.
基金supported by the research project within the program“Excellence Initiative-Research University”for the AGH University of Krakow(IDUB AGH,Action 21)Kun Zheng acknowledges financial support from AGH University of Krakow(No.16.16.210.476).
文摘Minimizing the thermal expansion coefficient(TEC)mismatch between the cathode and electrolyte in solid oxide fuel cells is crucial for achieving stable,durable operation and high performance.Recently,materials with negative thermal expansion(NTE)have at-tracted significant attention as effective additives for tailoring the thermomechanical properties of electrodes and enhancing cell durability.In this work,for the first time,single-phase NTE perovskite Sm_(0.85)Zn_(0.15)MnO_(3−δ)(SZM15)was successfully synthesized via the sol-gel method,eliminating the unwanted ZnO phase typically observed in materials obtained through the conventional solid-state reaction route.The sol-gel approach proved highly advantageous,offering low cost,robustness,excellent chemical homogeneity,precise compositional control,and high phase purity.After optimization of synthesis parameters,a negative TEC of approximately−6.5×10^(−6)K^(−1)was achieved in the 400-850℃range.SZM15 was then incorporated as an additive(10wt%-50wt%)into a SmBa0.5Sr0.5CoCuO_(5+δ)(SBSCCO)cathode to tune the thermomechanical properties with a La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(0.2)O_(3−δ)(LSGM)electrolyte,achieving a minimal TEC mismatch of only 1%.Notably,the SBSCCO+10wt%SZM15 composite cathode exhibited the lowest polarization resistance of 0.019Ω·cm^(2)at 900℃,showing approximately 70%lower than that of the pristine cathode.Excellent long-term stability after 100 h of operation was achieved.In addition,a high peak power density of 680 mW·cm^(−2)was achieved in a Ni-YSZ(yttria-stabilized zirconia)|YSZ|Ce_(0.9)Gd_(0.1)O_(2−δ)(GDC10)|SBSCCO+10wt%SZM15 anode-supported fuel cell at 850℃,highlighting the effectiveness of incorporating NTE materials as a promising strategy for regulating the thermomechanical properties and improving the long-term stability of intermediate temperature solid oxide fuel cells(IT-SOFCs).
