Among the various anodes,Li_(3)VO_(4)is a potential intercalation kind anode used in lithium-ion batteries(LIBs)that exhibits safer discharge voltage and higher capacity than graphite,a lower voltage plateau than Li_(...Among the various anodes,Li_(3)VO_(4)is a potential intercalation kind anode used in lithium-ion batteries(LIBs)that exhibits safer discharge voltage and higher capacity than graphite,a lower voltage plateau than Li_(4)Ti_(5)O_(12),and smaller volume difference in the Li^(+)intercalation/deintercalation process than metals and alloys.However,the comparatively low electronic conductivity,low initial coulombic efficiency(ICE)and serious capacity decay make the Li_(3)VO_(4)anode unviable when it comes to practical implementation.Therefore,this paper reviews the research progress of Li_(3)VO_(4)in recent years,mainly including the strategies of developing different synthesis methods to construct unique morphology,through coating,compositing or elemental doping to increase the ICE,electronic conductivity and the cycle constancy.Moreover,the application of Li_(3)VO_(4)anode materials in other energy storage systems is summarized.Lastly,the development prospect and challenge of Li_(3)VO_(4)anodes are discussed.展开更多
Li_(3)VO_4 has been considered as a promising insertion-type anode for lithium-ion batteries due to its high theoretical specific capacity and suitable operating voltage platform. However, this promising anode still s...Li_(3)VO_4 has been considered as a promising insertion-type anode for lithium-ion batteries due to its high theoretical specific capacity and suitable operating voltage platform. However, this promising anode still suffers from poor electrical conductivity. To address this issue, herein, a porous carbon supported Li_(3)VO_4 composites(Li_(3)VO_4/C) via a facile agitation-drying method combined with subsequent calcination is reported, in which Ketjen black carbon with high porosity, easy dispersion and excellent conductivity can serve as one of carbon sources. The Li_(3)VO_4/C composite prepared at 700 ℃ with a carbon content of~10% exhibits the optimized structure. The void space of the composite accommodates the volume changes during the charge/discharge process.Meanwhile, the carbon shell serves as a conductive skeleton to provide bi-continuous Li ions and electrons pathways. Electrochemical results reveal that the composite delivers a high initial discharge capacity of 572 m Ahág^(-1) and maintains a capacity of 442.9 m Ahág^(-1) after 100 cycles at 100 m Aág^(-1). Even at a high current density of 2 Aág^(-1), a considerable capacity of 243.8 m Ahág^(-1) can still be obtained. This work provides a promising approach for the practical application of Li_(3)VO_4 as anode material for LIBs.展开更多
In this work,tunable white up-conversion luminescence was achieved in the Yb^(3+),Er^(3+),Tm^(3+),Ho^(3+) codoped Na_(3)La(VO_(4))_(2) phosphors under 980 nm excitation.The emissions of three primary colors are mainly...In this work,tunable white up-conversion luminescence was achieved in the Yb^(3+),Er^(3+),Tm^(3+),Ho^(3+) codoped Na_(3)La(VO_(4))_(2) phosphors under 980 nm excitation.The emissions of three primary colors are mainly attributed to the ~2H_(11/2)/~4S_(3/2)→~4I_(15/2) transitions of Er^(3+),~1G_(4)→~3H_6 transition of Tm^(3+),and_5F_5→~5I_8 transition of Ho^(3+).White luminescence characteristics and mechanisms of up-conversion system were investigated in detail.In addition,the temperature sensing behaviors of multiple levels emission combinations for Na_(3)La(VO_(4))_(2):Yb^(3+),Er^(3+),Tm^(3+),Ho^(3+) were analyzed by employing thermally coupled and non-thermally coupled energy levels.Based on the emissions of ~3F_(2,3)/~1G_(4) energy levels,the maximum relative and absolute sensitivities were obtained to be 2.20%/K and 0.279 K^(-1).The design of up-conversion luminescence materials with high-quality white luminescence and excellent sensitivity performance is critical in the field of optical applications.展开更多
The safe operating voltage and low volume variation of Li_(3)VO_(4)(LVO)make it an ideal anode material for lithium(Li)-ion batteries.However,the insufficient understanding of the inner storage mechanism hinders the d...The safe operating voltage and low volume variation of Li_(3)VO_(4)(LVO)make it an ideal anode material for lithium(Li)-ion batteries.However,the insufficient understanding of the inner storage mechanism hinders the design of LVO-based electrodes.Herein,we investigate,for the first time,the Li-ion storage activity in LVO via Cl doping.Moreover,N-doped C coating was simultaneously achieved in the Cl doping process,resulting in synergistically improved reaction kinetics.As a result,the as-prepared Cl-doped Li_(3)VO_(4) coated with N-doped C(Cl-LVO@NC)electrodes deliver a discharge capacity of 884.1 mAh/g after 200 cycles at 0.2 A/g,which is the highest among all of the LVO-based electrodes.The Cl-LVO@NC electrodes also exhibit high-capacity retention of 331.1 mAh/g at 8.0 A/g and full capacity recovery after 5 periods of rate testing over 400 cycles.After 5000 cycles at 4.0 A/g,the discharge capacity can be maintained at 423.2 mAh/g,which is superior to most LVO-based electrodes.The Li-ion storage activity in LVO via Cl doping and significant improvement in the high-rate Li-ion storage reported in this work can be used as references for the design of advanced LVO-based electrodes for high-power applications.展开更多
Electrochemical potential and ion diffusion of electrode materials restrain the energy and power densities of lithium-ion batteries,and these challenges also remain in the intercalation-type Li_(3)VO_(4)(LVO).In this ...Electrochemical potential and ion diffusion of electrode materials restrain the energy and power densities of lithium-ion batteries,and these challenges also remain in the intercalation-type Li_(3)VO_(4)(LVO).In this work,the local[VO_(4)]coordination symmetry in LVO is broken by a higher concentration of oxygen vacancies(Vö),resulting in an increased average V–O bond length and a larger ligand field splitting.These alterations reduce the energy level of the lowest unoccupied orbitals(e^(*))and lift the electrochemical potential,resulting in a higher voltage output.Additionally,the broken local symmetry in Vö-LVO is found to reduce the band gap and expand the ion transport channels,which favors enhancing electronic conductivity and facilitates ion diffusion,thereby improving the electrochemical kinetics in the energy storage process.The local symmetry broken sample(Vö-LVO)achieves a significantly improved capacity of 532 mAh/g at 0.1 A/g in comparison with 394 mAh/g of pristine LVO,and long cycling stability with retained capacity of 398 mAh/g at 1 A/g over 500 cycles compared with 236 mAh/g of the pristine LVO.The fundamental understanding paves the way to exploit high-performance electrodes via ligand field engineering for next-generation rechargeable batteries.展开更多
Li_(3)VO_(4)has been a promising insertion anode material for Li-ion batteries,which has high theoretical capacity(up to~600 m Ah g^(-1))and safe Li insertion voltage(0.5–1 V vs.Li/Li^(+)).However,the low initial Cou...Li_(3)VO_(4)has been a promising insertion anode material for Li-ion batteries,which has high theoretical capacity(up to~600 m Ah g^(-1))and safe Li insertion voltage(0.5–1 V vs.Li/Li^(+)).However,the low initial Coulombic efficiency(ICE)has always been the bottleneck limiting its commercialisation.Here,we propose a facile pre-lithiation method to controllably elevate the ICE by the post-treatment of the prepared Li_(3)VO_(4)composite electrode based on an immersion reaction.In this process,the whole electrode was immersed in the liquid Li source,via which the ICE of the Li_(3)VO_(4)electrode can be controllably elevated from 80%to over 100%within 5 min of pre-lithiation.Rather than the traditional powder treatment for pre-lithiation,this process we proposed minimizes the impact of pre-lithiation on the battery assembly process.Moreover,we further investigated the effect of this pre-lithiation process on the functional components in the electrode.For the first time the ICE of Li_(3)VO_(4)electrode was elevated to 100%.As a result,the initial reversible capacity of LiFePO_(4)||Li_(3)VO_(4)full cell was improved from 44.0 to146.3 m Ah g-1,demonstrating the feasibility and great potential of the process.展开更多
Li_(3)VO_(4) is a promising electrode material for next-generation lithium-ion batteries(LIBs)due to its excellent specific capac-ity(592 mAh g^(−1)),suitable discharge voltage(0.5-1.0 V),and moderate volume change up...Li_(3)VO_(4) is a promising electrode material for next-generation lithium-ion batteries(LIBs)due to its excellent specific capac-ity(592 mAh g^(−1)),suitable discharge voltage(0.5-1.0 V),and moderate volume change upon charge/discharge,while it still suffers from low electronic conductivity that usually gives a poor rate capability,low initial coulombic efficiency,and large polarization,imposing a challenge on its practical applications.In this work,a partial surface phase transformation of Li_(3)VO_(4) was initiated via a freeze-drying method followed by a heat treatment in inert gas.Using this method,Li_(3)VO_(4) was integrated with a conductive layer LiVO_(2) and carbon matrix.The synergistic effect among Li_(3)VO_(4),LiVO_(2) layer,and carbon matrix was systematically studied by optimizing the treatment conditions.When treated at 600°C in Ar,Li_(3)VO_(4)-based composite delivered outstanding electrochemical properties,as expressed by a specific capacity(689 mAh g^(−1) at 0.1 A g^(−1) after 100 cycles),rate performance(i.e.,448 mAh g^(−1) at 2 A g^(−1)),and longtime cycle stability(523 mAh g^(−1) after 200 cycles at 0.2 A g^(−1)),which are superior to those without LiVO_(2) conductive layer when treated at the same temperature in air.The findings reported in this work may offer novel hints of preparing more advanced anodes and promote the applications of vanadate materials such as Li_(3)VO_(4) for next-generation lithium-ion batteries.展开更多
Semiconductor heterojunction plays a pivotal role in photocatalysis.However,the construction of a heterojunction with a fine microstructure usually requires complex synthetic procedures.Herein,a pH-adjusted one-step m...Semiconductor heterojunction plays a pivotal role in photocatalysis.However,the construction of a heterojunction with a fine microstructure usually requires complex synthetic procedures.Herein,a pH-adjusted one-step method was employed to controllably synthesize Ag_(4)V_(2)O_(7)/Ag_(3)VO_(4) heterojunction with a well-tuned 0D/1D hierarchical structure for the first time.It is noteworthy that the ordered stacking of vanadium oxide tetrahedron(VO_(3)-)guided by the pH value wisely realizes the in-situ growth of Ag_(4)V_(2)O_(7) nanoparticles on the surface of Ag_(3)VO_(4) nanorods.Furthermore,comprehensive characterization and calculation decipher the electronic structures of Ag_(4)V_(2)O_(7) and Ag_(3)VO_(4) and the formation of Z-scheme heterojunction,benefiting the visible light harvesting and carrier utilization.Such a new Ag_(4)V_(2)O_(7)/Ag_(3)VO_(4) heterojunction exhibits remarkable photocatalytic activity and excellent stability.Complete degradation of Rhodamine B(RhB)can be achieved in 10 min by the Ag_(4)V_(2)O_(7)/Ag_(3)VO_(4) heterojunction under visible light irradiation,demonstrating an outstanding reaction rate of 0.35 min^(−1) that is up to 84-fold higher than those of other silver vanadates.More importantly,this integration of synthesis technology and heterojunction design,based on the intrinsic crystal and electronic structures,could be inspiring for developing novel heterostructured materials with advanced performance.展开更多
基金supported by the National Natural Science Foundation,China(Nos.21773057,52071132 and U1904216)the Zhongyuan Thousand People Plan-The Zhongyuan Youth Talent Support Program(in Science and Technology),China(No.ZYQR201810139)+1 种基金the Innovative Funds Plan of Henan University of Technology,China(No.2020ZKCJ04)Fundamental Research Funds for the Henan Provincial Colleges and Universities in Henan University of Technology,China(No.2018RCJH01)。
文摘Among the various anodes,Li_(3)VO_(4)is a potential intercalation kind anode used in lithium-ion batteries(LIBs)that exhibits safer discharge voltage and higher capacity than graphite,a lower voltage plateau than Li_(4)Ti_(5)O_(12),and smaller volume difference in the Li^(+)intercalation/deintercalation process than metals and alloys.However,the comparatively low electronic conductivity,low initial coulombic efficiency(ICE)and serious capacity decay make the Li_(3)VO_(4)anode unviable when it comes to practical implementation.Therefore,this paper reviews the research progress of Li_(3)VO_(4)in recent years,mainly including the strategies of developing different synthesis methods to construct unique morphology,through coating,compositing or elemental doping to increase the ICE,electronic conductivity and the cycle constancy.Moreover,the application of Li_(3)VO_(4)anode materials in other energy storage systems is summarized.Lastly,the development prospect and challenge of Li_(3)VO_(4)anodes are discussed.
基金financially supported by the National Natural Science Foundation of China (Nos. 51874362 and51872334)the Natural Science Foundation of Hunan Province,China(No. 2018JJ1036)the National Key Research and Development Program of China (No. 2018YFB0104200)。
文摘Li_(3)VO_4 has been considered as a promising insertion-type anode for lithium-ion batteries due to its high theoretical specific capacity and suitable operating voltage platform. However, this promising anode still suffers from poor electrical conductivity. To address this issue, herein, a porous carbon supported Li_(3)VO_4 composites(Li_(3)VO_4/C) via a facile agitation-drying method combined with subsequent calcination is reported, in which Ketjen black carbon with high porosity, easy dispersion and excellent conductivity can serve as one of carbon sources. The Li_(3)VO_4/C composite prepared at 700 ℃ with a carbon content of~10% exhibits the optimized structure. The void space of the composite accommodates the volume changes during the charge/discharge process.Meanwhile, the carbon shell serves as a conductive skeleton to provide bi-continuous Li ions and electrons pathways. Electrochemical results reveal that the composite delivers a high initial discharge capacity of 572 m Ahág^(-1) and maintains a capacity of 442.9 m Ahág^(-1) after 100 cycles at 100 m Aág^(-1). Even at a high current density of 2 Aág^(-1), a considerable capacity of 243.8 m Ahág^(-1) can still be obtained. This work provides a promising approach for the practical application of Li_(3)VO_4 as anode material for LIBs.
基金Project supported by the National Natural Science Foundation of China (11904046,11974069,11504039)。
文摘In this work,tunable white up-conversion luminescence was achieved in the Yb^(3+),Er^(3+),Tm^(3+),Ho^(3+) codoped Na_(3)La(VO_(4))_(2) phosphors under 980 nm excitation.The emissions of three primary colors are mainly attributed to the ~2H_(11/2)/~4S_(3/2)→~4I_(15/2) transitions of Er^(3+),~1G_(4)→~3H_6 transition of Tm^(3+),and_5F_5→~5I_8 transition of Ho^(3+).White luminescence characteristics and mechanisms of up-conversion system were investigated in detail.In addition,the temperature sensing behaviors of multiple levels emission combinations for Na_(3)La(VO_(4))_(2):Yb^(3+),Er^(3+),Tm^(3+),Ho^(3+) were analyzed by employing thermally coupled and non-thermally coupled energy levels.Based on the emissions of ~3F_(2,3)/~1G_(4) energy levels,the maximum relative and absolute sensitivities were obtained to be 2.20%/K and 0.279 K^(-1).The design of up-conversion luminescence materials with high-quality white luminescence and excellent sensitivity performance is critical in the field of optical applications.
基金supported by the National Natural Science Foundation of China(No.52101262)Distinguished Youth Foundation of Hubei Province(2019CFA084)+1 种基金Educational offi ce of Hubei Province(Q20201201)the 111 project(D20015).
文摘The safe operating voltage and low volume variation of Li_(3)VO_(4)(LVO)make it an ideal anode material for lithium(Li)-ion batteries.However,the insufficient understanding of the inner storage mechanism hinders the design of LVO-based electrodes.Herein,we investigate,for the first time,the Li-ion storage activity in LVO via Cl doping.Moreover,N-doped C coating was simultaneously achieved in the Cl doping process,resulting in synergistically improved reaction kinetics.As a result,the as-prepared Cl-doped Li_(3)VO_(4) coated with N-doped C(Cl-LVO@NC)electrodes deliver a discharge capacity of 884.1 mAh/g after 200 cycles at 0.2 A/g,which is the highest among all of the LVO-based electrodes.The Cl-LVO@NC electrodes also exhibit high-capacity retention of 331.1 mAh/g at 8.0 A/g and full capacity recovery after 5 periods of rate testing over 400 cycles.After 5000 cycles at 4.0 A/g,the discharge capacity can be maintained at 423.2 mAh/g,which is superior to most LVO-based electrodes.The Li-ion storage activity in LVO via Cl doping and significant improvement in the high-rate Li-ion storage reported in this work can be used as references for the design of advanced LVO-based electrodes for high-power applications.
基金financially supported by the Natural Science Foundation of Fujian Province(2022J011269)the National Natural Science Foundation of China(52102277,52472238,52302193)+1 种基金the Fujian Provincial Key Laboratory of Functional Materials and Applications(fma2022005)the Fundamental Research Funds for the Central Universities,conducted by Tongji University。
文摘Electrochemical potential and ion diffusion of electrode materials restrain the energy and power densities of lithium-ion batteries,and these challenges also remain in the intercalation-type Li_(3)VO_(4)(LVO).In this work,the local[VO_(4)]coordination symmetry in LVO is broken by a higher concentration of oxygen vacancies(Vö),resulting in an increased average V–O bond length and a larger ligand field splitting.These alterations reduce the energy level of the lowest unoccupied orbitals(e^(*))and lift the electrochemical potential,resulting in a higher voltage output.Additionally,the broken local symmetry in Vö-LVO is found to reduce the band gap and expand the ion transport channels,which favors enhancing electronic conductivity and facilitates ion diffusion,thereby improving the electrochemical kinetics in the energy storage process.The local symmetry broken sample(Vö-LVO)achieves a significantly improved capacity of 532 mAh/g at 0.1 A/g in comparison with 394 mAh/g of pristine LVO,and long cycling stability with retained capacity of 398 mAh/g at 1 A/g over 500 cycles compared with 236 mAh/g of the pristine LVO.The fundamental understanding paves the way to exploit high-performance electrodes via ligand field engineering for next-generation rechargeable batteries.
基金supported by the National Natural Science Foundation of China(52072138)the Shenzhen Science and TechnologyProgram(JCYJ2022530160816038and JCYJ20220818100418040)+1 种基金the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(GZC20230879)the China Postdoctoral Science Foundation(2023M74247)。
文摘Li_(3)VO_(4)has been a promising insertion anode material for Li-ion batteries,which has high theoretical capacity(up to~600 m Ah g^(-1))and safe Li insertion voltage(0.5–1 V vs.Li/Li^(+)).However,the low initial Coulombic efficiency(ICE)has always been the bottleneck limiting its commercialisation.Here,we propose a facile pre-lithiation method to controllably elevate the ICE by the post-treatment of the prepared Li_(3)VO_(4)composite electrode based on an immersion reaction.In this process,the whole electrode was immersed in the liquid Li source,via which the ICE of the Li_(3)VO_(4)electrode can be controllably elevated from 80%to over 100%within 5 min of pre-lithiation.Rather than the traditional powder treatment for pre-lithiation,this process we proposed minimizes the impact of pre-lithiation on the battery assembly process.Moreover,we further investigated the effect of this pre-lithiation process on the functional components in the electrode.For the first time the ICE of Li_(3)VO_(4)electrode was elevated to 100%.As a result,the initial reversible capacity of LiFePO_(4)||Li_(3)VO_(4)full cell was improved from 44.0 to146.3 m Ah g-1,demonstrating the feasibility and great potential of the process.
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.21571176,21671077,21771075 and 21871106).
文摘Li_(3)VO_(4) is a promising electrode material for next-generation lithium-ion batteries(LIBs)due to its excellent specific capac-ity(592 mAh g^(−1)),suitable discharge voltage(0.5-1.0 V),and moderate volume change upon charge/discharge,while it still suffers from low electronic conductivity that usually gives a poor rate capability,low initial coulombic efficiency,and large polarization,imposing a challenge on its practical applications.In this work,a partial surface phase transformation of Li_(3)VO_(4) was initiated via a freeze-drying method followed by a heat treatment in inert gas.Using this method,Li_(3)VO_(4) was integrated with a conductive layer LiVO_(2) and carbon matrix.The synergistic effect among Li_(3)VO_(4),LiVO_(2) layer,and carbon matrix was systematically studied by optimizing the treatment conditions.When treated at 600°C in Ar,Li_(3)VO_(4)-based composite delivered outstanding electrochemical properties,as expressed by a specific capacity(689 mAh g^(−1) at 0.1 A g^(−1) after 100 cycles),rate performance(i.e.,448 mAh g^(−1) at 2 A g^(−1)),and longtime cycle stability(523 mAh g^(−1) after 200 cycles at 0.2 A g^(−1)),which are superior to those without LiVO_(2) conductive layer when treated at the same temperature in air.The findings reported in this work may offer novel hints of preparing more advanced anodes and promote the applications of vanadate materials such as Li_(3)VO_(4) for next-generation lithium-ion batteries.
基金gratefully acknowledge the financial support of the National Natural Science Foundation of China(Nos.52102068,52202058,and 52073156)Science and Technology on Advanced Functional Composite Laboratory(No.6142906200509)+1 种基金State Key Laboratory of New Ceramics&Fine Processing Tsinghua University(No.KF202112)the Natural Science Foundation of Jiangsu Province(No.20KJB430017)and NUPTSF(No.NY219162).
文摘Semiconductor heterojunction plays a pivotal role in photocatalysis.However,the construction of a heterojunction with a fine microstructure usually requires complex synthetic procedures.Herein,a pH-adjusted one-step method was employed to controllably synthesize Ag_(4)V_(2)O_(7)/Ag_(3)VO_(4) heterojunction with a well-tuned 0D/1D hierarchical structure for the first time.It is noteworthy that the ordered stacking of vanadium oxide tetrahedron(VO_(3)-)guided by the pH value wisely realizes the in-situ growth of Ag_(4)V_(2)O_(7) nanoparticles on the surface of Ag_(3)VO_(4) nanorods.Furthermore,comprehensive characterization and calculation decipher the electronic structures of Ag_(4)V_(2)O_(7) and Ag_(3)VO_(4) and the formation of Z-scheme heterojunction,benefiting the visible light harvesting and carrier utilization.Such a new Ag_(4)V_(2)O_(7)/Ag_(3)VO_(4) heterojunction exhibits remarkable photocatalytic activity and excellent stability.Complete degradation of Rhodamine B(RhB)can be achieved in 10 min by the Ag_(4)V_(2)O_(7)/Ag_(3)VO_(4) heterojunction under visible light irradiation,demonstrating an outstanding reaction rate of 0.35 min^(−1) that is up to 84-fold higher than those of other silver vanadates.More importantly,this integration of synthesis technology and heterojunction design,based on the intrinsic crystal and electronic structures,could be inspiring for developing novel heterostructured materials with advanced performance.
