Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation d...Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs anode.Herein,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for SIBs.Moreover,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 cycles.This work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.展开更多
Carbon materials are considered as promising anodes of sodium-ion batteries(SIBs)due to their low cost,high conductivity,and tunable interlayer spacing.However,the low specific capacity,inferior rate capability,and po...Carbon materials are considered as promising anodes of sodium-ion batteries(SIBs)due to their low cost,high conductivity,and tunable interlayer spacing.However,the low specific capacity,inferior rate capability,and poor initial Coulombic efficiency(ICE)limit the practical applications.Heteroatom doping is a feasible strategy to address such issues,and the synergistic effect enables dual-element co-doping to further enhance SIBs performances.Here,we synthesize a unique nitrogen(N)and sulfur(S)co-doped mesoporous carbon(SNC)using mesoporous silica as the hard stencil.The ingenious S doping enlarges interlayer spacings,increases defect densities,and enriches active sites.In parallel,the presence of S anions readjusts the center of p-band position in pyridinic-N and the electronic configuration of isolated N atom.Outstanding sodium-ion storage performance is achieved in SNC featured with remarkable ICE(83.8%),high-rate capability(150.0 mAh·g^(-1) at 40 A·g^(-1)),and long-cycle stability(241.6 mAh·g^(-1) at 5 A·g^(-1) after 1600 cycles).The sodium-ion storage mechanism is clarified by combining theory calculations and in-situ/ex-situ experimental characterizations.This work provides a new approach to synthesising dual-element co-doped carbon anodes for enhancing SIBs performances.展开更多
With the support by the National Natural Science Foundation of China,the research group led by Prof.Chen Liwei(陈立桅)at the Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO),Chinese Academy of Sciences in collab...With the support by the National Natural Science Foundation of China,the research group led by Prof.Chen Liwei(陈立桅)at the Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO),Chinese Academy of Sciences in collaboration with Prof.Chen Hongwei(陈宏伟)from Huaqiao University demonstrated a novel in situ wrapping strategy that leads to long-cycle life cathode for Li-S batteries,which was published in Nature Communications(2017,8:479).展开更多
Lithium-rich manganese-based cathodes(LRMs)have garnered significant attention as promising candidates for highenergy-density batteries due to their exceptional specific capacity exceeding 300 mAh/g,achieved through s...Lithium-rich manganese-based cathodes(LRMs)have garnered significant attention as promising candidates for highenergy-density batteries due to their exceptional specific capacity exceeding 300 mAh/g,achieved through synergistic anionic and cationic redox reactions.However,these materials face challenges including oxygen release-induced structural degradation and consequent capacity fading.To address these issues,strategies such as surface modification and bulk phase engineering have been explored.In this study,we developed a facile and cost-effective quenching approach that simultaneously modifies both surface and bulk characteristics.Multi-scale characterization and computational analysis reveal that rapid cooling partially preserves the high-temperature disordered phase in the bulk structure,thereby enhancing the structural stability.Concurrently,Li^(+)/H^(+)exchange at the surface forms a robust rock-salt/spinel passivation layer,effectively suppressing oxygen evolution and mitigating interfacial side reactions.This dual modification strategy demonstrates a synergistic stabilization effect.The enhanced oxygen redox activity coexists with the improved structural integrity,leading to superior electrochemical performance.The optimized cathode delivers an initial discharge capacity approaching 307.14 mAh/g at 0.1 C and remarkable cycling stability with 94.12%capacity retention after 200 cycles at 1 C.This study presents a straightforward and economical strategy for concurrent surface–bulk modification,offering valuable insights for designing high-capacity LRM cathodes with extended cycle life.展开更多
Lithium-ion batteries(LIBs) as energy storage devices play an important role in all aspects of our life. The increasing energy demand of the society requires LIBs with higher energy density and better performance. We ...Lithium-ion batteries(LIBs) as energy storage devices play an important role in all aspects of our life. The increasing energy demand of the society requires LIBs with higher energy density and better performance. We here develop a new and easy-to-scaleup sol-gel method to coat a surface protection layer on commercial LiCoO2cathode. We demonstrate that a proper thickness can improve the cycling life with a higher cut-off potential(4.5 V), larger energy capacity(180 mAh/g at 0.5 C) and better energy density(35% more compared to non-coated LiCoO2). The mechanism of the protection layer is also revealed by a combination of electron microscopy and synchrotron X-ray spectroscopy.展开更多
Lithium-ion batteries(LIBs)featuring a Ni-rich cathode exhibit increased specific capacity,but the establishment of a stable interphase through the implementation of a functional electrolyte strategy remains challengi...Lithium-ion batteries(LIBs)featuring a Ni-rich cathode exhibit increased specific capacity,but the establishment of a stable interphase through the implementation of a functional electrolyte strategy remains challenging.Especially when the battery is operated under high temperature,the trace water present in the electrolyte will accelerate the hydrolysis of the electrolyte and the resulting HF will further erode the interphase.In order to enhance the long-term cycling performance of graphite/LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)LIBs,herein,Tolylene-2,4-diisocyanate(TDI)additive containing lone-pair electrons is employed to formulate a novel bifunctional electrolyte aimed at eliminating H_(2)O/HF generated at elevated temperature.After 1000 cycles at 25℃,the battery incorporating the TDI-containing electrolyte exhibits an impressive capacity retention of 94%at 1 C.In contrast,the battery utilizing the blank electrolyte has a lower capacity retention of only 78%.Furthermore,after undergoing 550 cycles at 1 C under45℃,the inclusion of TDI results in a notable enhancement of capacity,increasing it from 68%to 80%.This indicates TDI has a favorable influence on the cycling performance of LIBs,especially at elevated temperatures.The analysis of the film formation mechanism suggests that the lone pair of electrons of the isocyanate group in TDI play a crucial role in inhibiting the generation of H_(2)O and HF,which leads to the formation of a thin and dense interphase.The existence of this interphase is thought to substantially enhance the cycling performance of the LIBs.This work not only improves the performance of graphite/NCM811 batteries at room temperature and high temperature by eliminating H_(2)O/HF but also presents a novel strategy for advancing functional electrolyte development.展开更多
Organic cathode materials hold great promise for rechargeable batteries due to their high theoretical capacity, sustainable resources, and low carbon footprint, yet suffer from low conductivity and high solubility in ...Organic cathode materials hold great promise for rechargeable batteries due to their high theoretical capacity, sustainable resources, and low carbon footprint, yet suffer from low conductivity and high solubility in liquid electrolytes, which result in inferior kinetics and poor cycling stability. Herein, we rationally design and synthesize a new conjugated carbonyl polymer(PTO-AQ) cathode with a unique donor-acceptor structure. The polymerization can effectively eliminate the dissolution of organic molecules, while the interlaced donor and acceptor units can endow the PTO-AQ polymer to serve as both donors and acceptors of electrons, thereby enhancing the electrical conductivity. Consequently, the PTO-AQ cathode exhibits high capacity,remarkable cycling stability, and high-rate performance in both Li and Na batteries. Notably, when paired with a Na-metal or hard carbon anode, the resulting Na batteries can stably operate for over 10,000 cycles with an extremely low-capacity decay rate(<0.5% per 100 cycles) and retain a high capacity of 66 m Ah g^(-1)at an ultra-high current density of 40 A g^(-1), representing a significant advancement in promoting organic batteries with long-cycling and ultra-fast charging.展开更多
MXene-based materials have gained considerable attention for lithium-sulfur(Li-S)batteries cathode materials due to their superior electric conductivity and high affinitive to polysulfides.However,there are still chal...MXene-based materials have gained considerable attention for lithium-sulfur(Li-S)batteries cathode materials due to their superior electric conductivity and high affinitive to polysulfides.However,there are still challenges in modifying the surface functional groups of MXene to further improve the electrochemical performance and increase the structure variety for MXene-based sulfur host.Herein,we report an efficient and flexible nucleophilic substitution(S_(N))strategy to modify the Ti_(3)C_(2)T_(x) surface terminations and purposefully designed Magnolol-modified Ti_(3)C_(2)T_(x)(M-Ti_(3)C_(2)T_(x))as powerful cathode host materials.Benefiting from more C-Ti-O bonds forming and diallyl groups terminations reducing after the dehalogenation and nucleophilic addition reactions,the given M-Ti_(3)C_(2)T_(x) electrode could effectively suppress the lithium polysulfides shuttling via chemisorption and C—S covalent bond formation.Besides,the Magnolol-modified Ti_(3)C_(2)T_(x) significantly accelerates polysulfide redox reaction and reduces the activation energy of Li_(2) S decomposition.As a result,the as-prepared M-Ti_(3)C_(2)T_(x) electrode displays an excellent rate capability and a high reversible capacity of 7.68 mAh cm^(-2)even under 7.2 mg cm^(-2)S-loaded with a low decay rate of 0.07%(from 2 nd cycle).This flexible surface-modified strategy for MXene terminations is expected to be extended to other diverse MXene applications.展开更多
Since Co_(2)VO_(4) possesses a solid spinel structure and a high degree of stability,it has gained interest as a possible anode material for sodium-ion batteries.However,the application of this electrode material is s...Since Co_(2)VO_(4) possesses a solid spinel structure and a high degree of stability,it has gained interest as a possible anode material for sodium-ion batteries.However,the application of this electrode material is still hampered by its poor electrical conductivity and severe volume expansion.Uniform Co_(2)VO_(4) nanoparticles(CVO)were grown on carbon nanotubes(CNTs)by a simple solvothermal method to form string-like conductive networks(CVO/CNTs).The flexible and highly conductive three-dimensional(3D)carbon nano tubes and small-sized CVO NPs can enhance the rapid transport of electrons,thereby enhancing the conductivity of the composite.String-like conductive network structures have a larger specific surface area,enhancing electron/ion transmission by fully contacting the electrolyte.The findings demonstrate the superior Na^(+)storing capability of the CVO/CNTs composite.The battery has a great rate performance(148.2 mAh·g^(-1)at 5 A·g^(-1))and outstanding long-term cycling performance(147.3 mAh·g^(-1)after 1000 cycles at 1A·g^(-1)).In high-rate,long-cycle sodium-ion batteries,CVO/CNTs composites offer a wide range of possible applications.展开更多
Rechargeable aqueous zinc-ion batteries(ZIBs)are regarded as a promising competition to lithium-ion batteries as energy storage devices,owing to their high safety and low cost.However,the development of high-performan...Rechargeable aqueous zinc-ion batteries(ZIBs)are regarded as a promising competition to lithium-ion batteries as energy storage devices,owing to their high safety and low cost.However,the development of high-performance ZIBs is largely hindered by the shortage of ideal cathode materials with high-rate capability and long-cycle stability.Herein,we address this bottleneck issue by the quenching-tailored surface chemistry of V_(2)O_(5) cathode nanomaterial.By rapid quenching from high temperatures,Al ions are doped into V_(2)O_(5) lattice(Al-V_(2)O_(5))and abundant oxygen vacancies are formed on the surface/nearsurface,which facilitate the desired rapid electron transfers.Our density functional theory(DFT)simulations elucidate that the doping of Al ions into V_(2)O_(5) remarkably reduces the Zn^(2+)-diffusion barriers and improves the electrical conductivity of V_(2)O_(5).As a proof-of-concept application,the thus-optimized AlV_(2)O_(5) cathode delivers a superior specific capacity of 532 m Ah g^(-1) at 0.1 A g^(-1) and a long-cycling life with76%capacity retention after 5000 cycles,as well as a good rate performance.This work provides not only a novel strategy for tuning the surface chemistry of V_(2)O_(5) to boost the Zn^(2+)storage but also a general pathway of modifying metal oxides with improved electrochemical performance.展开更多
Aqueous zinc ion batteries(AZIBs) have received great attention because of their non-toxicity,high safety,low cost,high abundance,and high specific power.However,their specific capacity is still low compared with lith...Aqueous zinc ion batteries(AZIBs) have received great attention because of their non-toxicity,high safety,low cost,high abundance,and high specific power.However,their specific capacity is still low compared with lithium ion battery,and current academic research interesting has been focused on developing new cathode materials with high specific capacity.In this study,a Mn/V hybrid polymer framework is designed by a simple self-polymerization scheme.During subsequent calcination,ultrafine VN quantum dots and MnO nanoparticles are generated in situ and stably encapsulated inside N-doped carbon(NC) shells to obtain a novel hybrid cathode NC@VN/MnO for AZIBs.According to the density functional theory(DFT) calculation,the hybrids of MnO and VN can generate both interfacial effects and built-in electric fields that significantly accelerate ion and electron transport by tuning the intrinsic electronic structure,thus enhancing electrochemical performance.A synergistic strategy of composition and structural design allows the rechargeable AZIBs to achieve low-cost and excellent long-cycle performance based on a relay type collaboration at different cycling stages.Consequently,the NC@VN/MnO cathode has output a capacity of 108.3 mA h g^(-1)after 12,000 cycles at 10 A g^(-1).These results clearly and fully demonstrate the advantages of the hybrid cathode NC@VN/MnO.展开更多
Aqueous zinc-ion batteries(ZIBs)have attracted increasing attention due to their low cost and high safety.MoS_(2) is a promising cathode material for aqueous ZIBs due to its favorable Zn^(2+)accommodation ability.Howe...Aqueous zinc-ion batteries(ZIBs)have attracted increasing attention due to their low cost and high safety.MoS_(2) is a promising cathode material for aqueous ZIBs due to its favorable Zn^(2+)accommodation ability.However,the structural strain and large volume changes during intercalation/deintercalation lead to exfoliation of active materials from substrate and cause irreversible capacity fading.In this work,a highly stable cathode was developed by designing a hierarchical carbon nanosheet-confined defective MoS_(x)material(CNS@MoS_(x)).This cathode material exhibits an excellent cycling stability with high capacity retention of 88.3%and~100%Coulombic efficiency after 400 cycles at 1.2 A·g^(-1),much superior compared to bare MoS_(2).Density functional theory(DFT)calculations combined with experiments illustrate that the promising electrochemical properties of CNS@MoS_(x)are due to the unique porous conductive structure of CNS with abundant active sites to anchor MoS_(x)via strong chemical bonding,enabling MoS_(x)to be firmly confined on the substrate.Moreover,this unique hierarchical complex structure ensures the fast migration of Zn^(2+)within MoS_(x)interlayer.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.U1904173 and 52272219)the Key Research Projects of Henan Provincial Department of Education(No.19A150043)+2 种基金the Natural Science Foundation of Henan Province(Nos.202300410330 and 222300420276)the Nanhu Scholars Program for Young Scholars of Xinyang Normal Universitythe Xinyang Normal University Analysis&Testing Center。
文摘Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs anode.Herein,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for SIBs.Moreover,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 cycles.This work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.
基金supported by the National Natural Science Foundation of China(Nos.92164103 and U24A2055)the National Key R&D Program of China(No.2021YFA1200800)+2 种基金Natural Science Foundation of Hubei Province(No.2024AFA052)Wuhan Science and Technology Bureau(Knowledge Innovation Program of Wuhan-Basic Research,No.2023010201010067)the Fundamental Research Funds for the Central Universities(No.2042023kf0187).
文摘Carbon materials are considered as promising anodes of sodium-ion batteries(SIBs)due to their low cost,high conductivity,and tunable interlayer spacing.However,the low specific capacity,inferior rate capability,and poor initial Coulombic efficiency(ICE)limit the practical applications.Heteroatom doping is a feasible strategy to address such issues,and the synergistic effect enables dual-element co-doping to further enhance SIBs performances.Here,we synthesize a unique nitrogen(N)and sulfur(S)co-doped mesoporous carbon(SNC)using mesoporous silica as the hard stencil.The ingenious S doping enlarges interlayer spacings,increases defect densities,and enriches active sites.In parallel,the presence of S anions readjusts the center of p-band position in pyridinic-N and the electronic configuration of isolated N atom.Outstanding sodium-ion storage performance is achieved in SNC featured with remarkable ICE(83.8%),high-rate capability(150.0 mAh·g^(-1) at 40 A·g^(-1)),and long-cycle stability(241.6 mAh·g^(-1) at 5 A·g^(-1) after 1600 cycles).The sodium-ion storage mechanism is clarified by combining theory calculations and in-situ/ex-situ experimental characterizations.This work provides a new approach to synthesising dual-element co-doped carbon anodes for enhancing SIBs performances.
文摘With the support by the National Natural Science Foundation of China,the research group led by Prof.Chen Liwei(陈立桅)at the Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO),Chinese Academy of Sciences in collaboration with Prof.Chen Hongwei(陈宏伟)from Huaqiao University demonstrated a novel in situ wrapping strategy that leads to long-cycle life cathode for Li-S batteries,which was published in Nature Communications(2017,8:479).
基金supported by the National Key Research and Development Program of China(Grant No.2022YFB2502200)the National Natural Science Foundation of China(Grant Nos.52325207,22239003,and 22393904).
文摘Lithium-rich manganese-based cathodes(LRMs)have garnered significant attention as promising candidates for highenergy-density batteries due to their exceptional specific capacity exceeding 300 mAh/g,achieved through synergistic anionic and cationic redox reactions.However,these materials face challenges including oxygen release-induced structural degradation and consequent capacity fading.To address these issues,strategies such as surface modification and bulk phase engineering have been explored.In this study,we developed a facile and cost-effective quenching approach that simultaneously modifies both surface and bulk characteristics.Multi-scale characterization and computational analysis reveal that rapid cooling partially preserves the high-temperature disordered phase in the bulk structure,thereby enhancing the structural stability.Concurrently,Li^(+)/H^(+)exchange at the surface forms a robust rock-salt/spinel passivation layer,effectively suppressing oxygen evolution and mitigating interfacial side reactions.This dual modification strategy demonstrates a synergistic stabilization effect.The enhanced oxygen redox activity coexists with the improved structural integrity,leading to superior electrochemical performance.The optimized cathode delivers an initial discharge capacity approaching 307.14 mAh/g at 0.1 C and remarkable cycling stability with 94.12%capacity retention after 200 cycles at 1 C.This study presents a straightforward and economical strategy for concurrent surface–bulk modification,offering valuable insights for designing high-capacity LRM cathodes with extended cycle life.
基金supported by Callahan Faculty Scholar Endowment Fund from Oregon State University,USA
文摘Lithium-ion batteries(LIBs) as energy storage devices play an important role in all aspects of our life. The increasing energy demand of the society requires LIBs with higher energy density and better performance. We here develop a new and easy-to-scaleup sol-gel method to coat a surface protection layer on commercial LiCoO2cathode. We demonstrate that a proper thickness can improve the cycling life with a higher cut-off potential(4.5 V), larger energy capacity(180 mAh/g at 0.5 C) and better energy density(35% more compared to non-coated LiCoO2). The mechanism of the protection layer is also revealed by a combination of electron microscopy and synchrotron X-ray spectroscopy.
基金financially supported by the Scientific and Technological Plan Projects of Guangzhou City(202103040001),P.R.Chinathe Project of Science and Technology Department of Henan Province(222102240074)the Key Research Programs of Higher Education Institutions of Henan Province(24B150009)。
文摘Lithium-ion batteries(LIBs)featuring a Ni-rich cathode exhibit increased specific capacity,but the establishment of a stable interphase through the implementation of a functional electrolyte strategy remains challenging.Especially when the battery is operated under high temperature,the trace water present in the electrolyte will accelerate the hydrolysis of the electrolyte and the resulting HF will further erode the interphase.In order to enhance the long-term cycling performance of graphite/LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)LIBs,herein,Tolylene-2,4-diisocyanate(TDI)additive containing lone-pair electrons is employed to formulate a novel bifunctional electrolyte aimed at eliminating H_(2)O/HF generated at elevated temperature.After 1000 cycles at 25℃,the battery incorporating the TDI-containing electrolyte exhibits an impressive capacity retention of 94%at 1 C.In contrast,the battery utilizing the blank electrolyte has a lower capacity retention of only 78%.Furthermore,after undergoing 550 cycles at 1 C under45℃,the inclusion of TDI results in a notable enhancement of capacity,increasing it from 68%to 80%.This indicates TDI has a favorable influence on the cycling performance of LIBs,especially at elevated temperatures.The analysis of the film formation mechanism suggests that the lone pair of electrons of the isocyanate group in TDI play a crucial role in inhibiting the generation of H_(2)O and HF,which leads to the formation of a thin and dense interphase.The existence of this interphase is thought to substantially enhance the cycling performance of the LIBs.This work not only improves the performance of graphite/NCM811 batteries at room temperature and high temperature by eliminating H_(2)O/HF but also presents a novel strategy for advancing functional electrolyte development.
基金supported by the National Natural Science Foundation of China (22005108)the Natural Science Foundation of Guangdong Province (2022B1515020005, 2023B1515130004, 2023A1515012032)+1 种基金the Guangzhou Science and Technology Foundation (2024A04J4192)the Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) of Nankai University。
文摘Organic cathode materials hold great promise for rechargeable batteries due to their high theoretical capacity, sustainable resources, and low carbon footprint, yet suffer from low conductivity and high solubility in liquid electrolytes, which result in inferior kinetics and poor cycling stability. Herein, we rationally design and synthesize a new conjugated carbonyl polymer(PTO-AQ) cathode with a unique donor-acceptor structure. The polymerization can effectively eliminate the dissolution of organic molecules, while the interlaced donor and acceptor units can endow the PTO-AQ polymer to serve as both donors and acceptors of electrons, thereby enhancing the electrical conductivity. Consequently, the PTO-AQ cathode exhibits high capacity,remarkable cycling stability, and high-rate performance in both Li and Na batteries. Notably, when paired with a Na-metal or hard carbon anode, the resulting Na batteries can stably operate for over 10,000 cycles with an extremely low-capacity decay rate(<0.5% per 100 cycles) and retain a high capacity of 66 m Ah g^(-1)at an ultra-high current density of 40 A g^(-1), representing a significant advancement in promoting organic batteries with long-cycling and ultra-fast charging.
基金the support from CNPC Innovation Found(2021DQ02-1001)Liao Ning Revitalization Talents Program(XLYC1907144)Xinghai Talent Cultivation Plan(X20200303)。
文摘MXene-based materials have gained considerable attention for lithium-sulfur(Li-S)batteries cathode materials due to their superior electric conductivity and high affinitive to polysulfides.However,there are still challenges in modifying the surface functional groups of MXene to further improve the electrochemical performance and increase the structure variety for MXene-based sulfur host.Herein,we report an efficient and flexible nucleophilic substitution(S_(N))strategy to modify the Ti_(3)C_(2)T_(x) surface terminations and purposefully designed Magnolol-modified Ti_(3)C_(2)T_(x)(M-Ti_(3)C_(2)T_(x))as powerful cathode host materials.Benefiting from more C-Ti-O bonds forming and diallyl groups terminations reducing after the dehalogenation and nucleophilic addition reactions,the given M-Ti_(3)C_(2)T_(x) electrode could effectively suppress the lithium polysulfides shuttling via chemisorption and C—S covalent bond formation.Besides,the Magnolol-modified Ti_(3)C_(2)T_(x) significantly accelerates polysulfide redox reaction and reduces the activation energy of Li_(2) S decomposition.As a result,the as-prepared M-Ti_(3)C_(2)T_(x) electrode displays an excellent rate capability and a high reversible capacity of 7.68 mAh cm^(-2)even under 7.2 mg cm^(-2)S-loaded with a low decay rate of 0.07%(from 2 nd cycle).This flexible surface-modified strategy for MXene terminations is expected to be extended to other diverse MXene applications.
基金financially supported by the National Key Research and Development Project (No.2018YFE0124800)the National Nature Science Foundation of China (No.51702157)。
文摘Since Co_(2)VO_(4) possesses a solid spinel structure and a high degree of stability,it has gained interest as a possible anode material for sodium-ion batteries.However,the application of this electrode material is still hampered by its poor electrical conductivity and severe volume expansion.Uniform Co_(2)VO_(4) nanoparticles(CVO)were grown on carbon nanotubes(CNTs)by a simple solvothermal method to form string-like conductive networks(CVO/CNTs).The flexible and highly conductive three-dimensional(3D)carbon nano tubes and small-sized CVO NPs can enhance the rapid transport of electrons,thereby enhancing the conductivity of the composite.String-like conductive network structures have a larger specific surface area,enhancing electron/ion transmission by fully contacting the electrolyte.The findings demonstrate the superior Na^(+)storing capability of the CVO/CNTs composite.The battery has a great rate performance(148.2 mAh·g^(-1)at 5 A·g^(-1))and outstanding long-term cycling performance(147.3 mAh·g^(-1)after 1000 cycles at 1A·g^(-1)).In high-rate,long-cycle sodium-ion batteries,CVO/CNTs composites offer a wide range of possible applications.
基金partially supported by the National Natural Science Foundation of China(Grant Nos.21771030,12004324)the Guangdong Basic and Applied Basic Research Foundation(2019A1515110859)+1 种基金the support by MOE,Singapore Ministry of Education(MOE2018-T2-295,Singapore),for research of this work conducted at the National University of Singaporethe financial support from China Scholarship Council(CSC No.202006060158)。
文摘Rechargeable aqueous zinc-ion batteries(ZIBs)are regarded as a promising competition to lithium-ion batteries as energy storage devices,owing to their high safety and low cost.However,the development of high-performance ZIBs is largely hindered by the shortage of ideal cathode materials with high-rate capability and long-cycle stability.Herein,we address this bottleneck issue by the quenching-tailored surface chemistry of V_(2)O_(5) cathode nanomaterial.By rapid quenching from high temperatures,Al ions are doped into V_(2)O_(5) lattice(Al-V_(2)O_(5))and abundant oxygen vacancies are formed on the surface/nearsurface,which facilitate the desired rapid electron transfers.Our density functional theory(DFT)simulations elucidate that the doping of Al ions into V_(2)O_(5) remarkably reduces the Zn^(2+)-diffusion barriers and improves the electrical conductivity of V_(2)O_(5).As a proof-of-concept application,the thus-optimized AlV_(2)O_(5) cathode delivers a superior specific capacity of 532 m Ah g^(-1) at 0.1 A g^(-1) and a long-cycling life with76%capacity retention after 5000 cycles,as well as a good rate performance.This work provides not only a novel strategy for tuning the surface chemistry of V_(2)O_(5) to boost the Zn^(2+)storage but also a general pathway of modifying metal oxides with improved electrochemical performance.
基金supported by the National Natural Science Foundation of China,China (51772205, 52073212)。
文摘Aqueous zinc ion batteries(AZIBs) have received great attention because of their non-toxicity,high safety,low cost,high abundance,and high specific power.However,their specific capacity is still low compared with lithium ion battery,and current academic research interesting has been focused on developing new cathode materials with high specific capacity.In this study,a Mn/V hybrid polymer framework is designed by a simple self-polymerization scheme.During subsequent calcination,ultrafine VN quantum dots and MnO nanoparticles are generated in situ and stably encapsulated inside N-doped carbon(NC) shells to obtain a novel hybrid cathode NC@VN/MnO for AZIBs.According to the density functional theory(DFT) calculation,the hybrids of MnO and VN can generate both interfacial effects and built-in electric fields that significantly accelerate ion and electron transport by tuning the intrinsic electronic structure,thus enhancing electrochemical performance.A synergistic strategy of composition and structural design allows the rechargeable AZIBs to achieve low-cost and excellent long-cycle performance based on a relay type collaboration at different cycling stages.Consequently,the NC@VN/MnO cathode has output a capacity of 108.3 mA h g^(-1)after 12,000 cycles at 10 A g^(-1).These results clearly and fully demonstrate the advantages of the hybrid cathode NC@VN/MnO.
基金The authors acknowledge the financial support by the National Natural Science Foundation of China(Nos.21922501,21625102,and 21471018)the China National Petroleum Corporation Research Fund Program,and the Research Institute of Petroleum Exploration and Development Research Fund Program.
文摘Aqueous zinc-ion batteries(ZIBs)have attracted increasing attention due to their low cost and high safety.MoS_(2) is a promising cathode material for aqueous ZIBs due to its favorable Zn^(2+)accommodation ability.However,the structural strain and large volume changes during intercalation/deintercalation lead to exfoliation of active materials from substrate and cause irreversible capacity fading.In this work,a highly stable cathode was developed by designing a hierarchical carbon nanosheet-confined defective MoS_(x)material(CNS@MoS_(x)).This cathode material exhibits an excellent cycling stability with high capacity retention of 88.3%and~100%Coulombic efficiency after 400 cycles at 1.2 A·g^(-1),much superior compared to bare MoS_(2).Density functional theory(DFT)calculations combined with experiments illustrate that the promising electrochemical properties of CNS@MoS_(x)are due to the unique porous conductive structure of CNS with abundant active sites to anchor MoS_(x)via strong chemical bonding,enabling MoS_(x)to be firmly confined on the substrate.Moreover,this unique hierarchical complex structure ensures the fast migration of Zn^(2+)within MoS_(x)interlayer.
