The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reducti...The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by NH3.Four different methods,namely pre-impregnation,post-impregnation,coimpregnation,and co-precipitation,were used to synthesize a series of V2 O5-WO3-TiO2-CeO2-ZrO2 catalysts.The catalysts were characterized by XRD,BET,NH3-TPD,XPS,and H2-TPR techniques.Moreover,the activity and anti-K poisoning performance were tested by an NH3-SCR model reaction.The results show that the introduction of Ce^4+and Zr^4+can improve the catalytic performance of V2O5-WO3/TiO2 catalyst,but the impregnation method cannot enhance the anti-K poisoning performance.Ce^4+and Zr^4+introduced by co-precipitation method can effectively improve the tolerance of K,which is mainly due to the incorporation of Ce^4+and Zr^4+into TiO2 lattice to form a uniform TiO2-CeO2-ZrO2 solid solution,resulting in the optimal surface acidity and redox performance,and reducing the decreases caused by Kpoisoning.Furthermore,based on the best introduction method,we further optimized the molar ratio of Ce^4+/Zr^4+,It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce^4+/Zr^4+is 2:1.展开更多
Sodium-ion batteries(SIBs)are the promising rechargeable batteries in large-scale energy storage systems for their low cost,high safety,wide temperature range adaptability,environmental friendliness and excellent fast...Sodium-ion batteries(SIBs)are the promising rechargeable batteries in large-scale energy storage systems for their low cost,high safety,wide temperature range adaptability,environmental friendliness and excellent fast-charging capabilities.Significant research endeavors in SIBs have focused on the exploration of high-performance electrode materials and thorough investigation of their mechanisms.Na_(2)FePO_(4)F(NFPF)is one of potential cathode materials because of low cost,minimal volume strain and extended cycle performance.This review summarizes the crystal structure,sodium ion migration pathways,and synthesis methods of NFPF and discusses the effect of various strategies including hybridization with carbon materials,ion doping,morphology control and electrolyte optimization on its electrochemical performance.Additionally,the application of the NFPF in different batteries is summarized.Finally,the challenges and future directions of NFPF are proposed.This review is both timely and important for promoting the applications of cost-effective NFPF.展开更多
In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) o...In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF.展开更多
Monocrystal LiMn_(0. 6)Fe_(0. 4)PO_4 cathode material was obtained via hydrothermal method at 180℃ for 10 h without any surfactant. The effects of hydrothermal time on the phase and morphology of the material were di...Monocrystal LiMn_(0. 6)Fe_(0. 4)PO_4 cathode material was obtained via hydrothermal method at 180℃ for 10 h without any surfactant. The effects of hydrothermal time on the phase and morphology of the material were discussed.By controlling the reaction solutions, the rodlike, flowerlike,and strawlike LiMn_(0.6)Fe_(0.4)PO_4 cathode materials were synthesized. Electrochemical performances show that the rodlike LiMn_(0. 6)Fe_(0. 4)PO_4 has the best electrochemical properties. The initial discharge capacity of the rodlike structure is 106.4 mAh·g^(-1), which is higher than those of flowerlike and strawlike materials.展开更多
LiMn2O4 spinel cathode materials were modified with 2 wt.%Li-M-PO4（M=Co,Ni,Mn） by polyol synthesis method.The phosphate surface-modified LiMn2O4 cathode materials were physically characterized by X-ray diffraction（...LiMn2O4 spinel cathode materials were modified with 2 wt.%Li-M-PO4（M=Co,Ni,Mn） by polyol synthesis method.The phosphate surface-modified LiMn2O4 cathode materials were physically characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM） and energy dispersive X-ray spectroscopy（EDS）.The charge-discharge test showed that the cycling and rate capacities of LiMn2O4 cathode materials were significantly enhanced by stabilizing the electrode surface with phosphate.展开更多
Normal spinel LiMn 2O 4 was synthesized by sol-gel method using lithium nitrate,manganese nitrate,citric acid and ethylene glycol as raw materials. LiMn 2O 4 was characterized by XRD,TG-DTA,IR,SEM and AAS.The opti...Normal spinel LiMn 2O 4 was synthesized by sol-gel method using lithium nitrate,manganese nitrate,citric acid and ethylene glycol as raw materials. LiMn 2O 4 was characterized by XRD,TG-DTA,IR,SEM and AAS.The optimum conditions for the synthesis were explored.Citric acid and ethylene glycol were mixed with molar ratio of 0.25,and the mixture was esterified at 140℃ for 4 hours.Then lithium nitrate and manganese nitrate were added with molar ratio of 0.6. In the system,the total molar of cations was equal to that of citric acid. At last, reflux the system at 105℃ for 2 hours. Dried gel was fired at 600℃ for 8 hours. Particle diameters of raw product were about 100 nm mainly. Further research shows that lithium ion of LiMn 2O 4 is easy to be extracted,and normal spinel λ-MnO 2 can be obtained after lithium ion extraction.展开更多
Using the highly accurate G4 method, we computed the thermodynamic data of 1287 possible reaction products under a wide range of reaction conditions in the Fischer-Tropcsh synthesis (FTS) process. These accurate therm...Using the highly accurate G4 method, we computed the thermodynamic data of 1287 possible reaction products under a wide range of reaction conditions in the Fischer-Tropcsh synthesis (FTS) process. These accurate thermodynamic data provide basic thermodynamic quantities for the actual chemical engineering process and are useful in analyzing product distribution because FTS demonstrates many features of an equilibrium-controlled system. Our results show that the number of thermodynamically allowed products to increase when lowering temperature, raising pressure, and raising H2/CO ratio. At low temperature, high pressure and high H2/CO ratio, many products are thermodynamically allowed and the selectivity of product has to be controlled by kinetic factors. On the other hand, high selectivity of lighter products can be realized in thermodynamics by raising temperature and lowering pressure. We found that the equilibrium product yield will reach a maximum and remain unchanged when lowering temperature, raising pressure, and raising H2/CO ratio to some limits, implying that optimizing reaction conditions has no effect on equilibrium product yields beyond these limits. The thermodynamic analysis is also useful in designing and evaluating FTS reaction mechanisms. We found that reaction pathways through formaldehyde should be discarded because of its extremely low equilibrium yield. Recently, in the FTS process using metal-oxide-zeolite catalysts for the highly selective production of C2-C4 olefins and aromatic hydrocarbons, there are several guesses on the possible reaction intermediates entering the zeolite channel. Our results show that ketene, methanol, and dimethyl ether are three possible reaction intermediates.展开更多
Spinel-type lithium and titanium composite oxide Li4TisO12 was successfully synthesized via a novel hydrolysis method followed by calcination using titanium tetrachloride （TIC14） and lithium hydroxide （LiOH.H2O） a...Spinel-type lithium and titanium composite oxide Li4TisO12 was successfully synthesized via a novel hydrolysis method followed by calcination using titanium tetrachloride （TIC14） and lithium hydroxide （LiOH.H2O） as raw materials. Three major factors, including LiOH con- centration, LiOH dosage, and hydrolysis temperature were studied for optimizing the synthetic conditions to obtain a phase-pure Li4Ti5012. The physical and electrochemical properties of samples were characterized by X-ray dif- fraction （XRD）, thermogravimetric analysis （TGA）, fourier transform infrared spectroscopy （FT-IR）, scanning electron microscopy （SEM）, and constant current discharge-charge test. The FT-IR results indicate the presence of [TiO6] octahedra. The SEM images show that the Li4Ti5O12 pre- cursor obtained is an amorphous solid with an irregular and rough morphology. It is revealed that the phase-pure spinel Li4Ti5O12 powders with well crystallization and regular morphology can be obtained by calcining the precursor at 800 ℃ for 6 h. The constant current discharge-charge tests indicate that the Li4TisO12 material delivers an excellent cycling ability, maintaining 93.8 % of its initial specific capacity after 60 cycles at a current density of 0.5C.展开更多
Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to thei...Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to their exceptional hydrogen binding energy,exhibit remarkable catalytic activity and long-term stability in the hydrogen evolution reaction(HER).However,the restricted accessibility and exorbitant cost of noble-metal materials pose obstacles to their extensive adoption in industrial contexts.This review investigates strategies aimed at reducing the dependence on noble-metal electrocatalysts and developing a cost-effective alkaline HER catalyst,while considering the principles of sustainable development.The initial discussion covers the fundamental principle of HER,followed by an overview of prevalent techniques for synthesizing catalysts based on noble metals,along with a thorough examination of recent advancements.The subsequent discussion focuses on the strategies employed to improve noble metalbased catalysts,including enhancing the intrinsic activity at active sites and increasing the quantity of active sites.Ultimately,this investigation concludes by examining the present state and future direction of research in the field of electrocatalysis for the HER.展开更多
With the boom in electric vehicles(EVs),there is an increasing demand for high-performance lithium-ion batteries.Lithium manganese iron phosphate(LMFP)has emerged as an enhanced variation of LiFePO4(LFP),offering an e...With the boom in electric vehicles(EVs),there is an increasing demand for high-performance lithium-ion batteries.Lithium manganese iron phosphate(LMFP)has emerged as an enhanced variation of LiFePO4(LFP),offering an energy density 10%–20%greater than that of LFP.Structural distortion caused by the Jahn–Teller effect decreases the capacity and voltage platform,thus restricting the commercialization of this material.Herein,ideas to overcome these challenges,including the crystal structure of LMFP and strategies to mitigate the Jahn–Teller distortion,are first explored.Then,the migration pathways of Li+during charging and discharging and the phase transition mechanisms that affect the material’s performance are discussed.Next,the optimal Mn:Fe ratio for achieving the desired performance is described.The influences of various synthesis and modification methods on the morphology and structure of LMFP are reviewed.Additionally,different modification techniques,such as doping and coating,to enhance the performance of LMFP are highlighted.Finally,an overview of the current state of research on the recycling and reuse of LMFP is provided.By addressing these key topics,this paper offers a theoretical foundation for the further development of LMFP,thus contributing to its eventual commercialization.展开更多
With the rapid development of new energy and the high proportion of new energy connected to the grid,energy storage has become the leading technology driving significant adjustments in the global energy landscape.Elec...With the rapid development of new energy and the high proportion of new energy connected to the grid,energy storage has become the leading technology driving significant adjustments in the global energy landscape.Electrochemical energy storage,as the most popular and promising energy storage method,has received extensive attention.Currently,the most widely used energy storage method is metal-ion secondary batteries,whose performance mainly depends on the cathode material.Prussian blue analogues(PBAs)have a unique open framework structures that allow quick and reversible insertion/extraction of metal ions such as Na^(+),K^(+),Zn^(2+),Li^(+)etc.,thus attracting widespread attention.The advantages of simple synthesis process,abundant resources,and low cost also distinguish it from its counterparts.Unfortunately,the crystal water and structural defects in the PBAs lattice that is generated during the synthesis process,as well as the low Na content,significantly affect their electrochemical performance.This paper focuses on PBAs’synthesis methods,crystal structure,modification strategies,and their potential applications as cathode materials for various metal ion secondary batteries and looks forward to their future development direction.展开更多
基金Project supported by the National Natural Science Foundation of China(21876168)the Key Projects for Common Key Technology Innovation in Key Industries in Chongqing(cstc2016zdcy-ztzx0020-01)+1 种基金Youth Innovation Promotion Association CAS(2019376)the Graduate Innovation Project of Chongqing Technology and Business University(yjscxx201803-028-22)。
文摘The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by NH3.Four different methods,namely pre-impregnation,post-impregnation,coimpregnation,and co-precipitation,were used to synthesize a series of V2 O5-WO3-TiO2-CeO2-ZrO2 catalysts.The catalysts were characterized by XRD,BET,NH3-TPD,XPS,and H2-TPR techniques.Moreover,the activity and anti-K poisoning performance were tested by an NH3-SCR model reaction.The results show that the introduction of Ce^4+and Zr^4+can improve the catalytic performance of V2O5-WO3/TiO2 catalyst,but the impregnation method cannot enhance the anti-K poisoning performance.Ce^4+and Zr^4+introduced by co-precipitation method can effectively improve the tolerance of K,which is mainly due to the incorporation of Ce^4+and Zr^4+into TiO2 lattice to form a uniform TiO2-CeO2-ZrO2 solid solution,resulting in the optimal surface acidity and redox performance,and reducing the decreases caused by Kpoisoning.Furthermore,based on the best introduction method,we further optimized the molar ratio of Ce^4+/Zr^4+,It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce^4+/Zr^4+is 2:1.
基金supported by National Natural Science Foundation of China(No.52064031)Natural Science Foundation of Yunnan Province(Nos.202301BE070001–014,202301AT070150,202402AB080001)the Analysis and Testing Foundation of Kunming University of Science and Technology(No.2022T20210182)。
文摘Sodium-ion batteries(SIBs)are the promising rechargeable batteries in large-scale energy storage systems for their low cost,high safety,wide temperature range adaptability,environmental friendliness and excellent fast-charging capabilities.Significant research endeavors in SIBs have focused on the exploration of high-performance electrode materials and thorough investigation of their mechanisms.Na_(2)FePO_(4)F(NFPF)is one of potential cathode materials because of low cost,minimal volume strain and extended cycle performance.This review summarizes the crystal structure,sodium ion migration pathways,and synthesis methods of NFPF and discusses the effect of various strategies including hybridization with carbon materials,ion doping,morphology control and electrolyte optimization on its electrochemical performance.Additionally,the application of the NFPF in different batteries is summarized.Finally,the challenges and future directions of NFPF are proposed.This review is both timely and important for promoting the applications of cost-effective NFPF.
基金Project(51104185)supported by the National Natural Science Foundation of ChinaProject(2010QZZD003)supported by the Key Project of Central South University of Fundamental Research Funds for the Central Universities of China
文摘In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF.
基金financially supported by the National Natural Science Foundation of China (Nos. 21231005 and 51071087)the Major State Basic Research Development Program of China(Nos. 2011CB935900 and 2010CB631303)+2 种基金the Discipline Innovative Engineering Plan (B12015)the Research Fund for the Doctoral Program of Higher Education of China (No.20120031110001)the Tianjin Science & Technology Project (No. 10SYSYJC27600)
文摘Monocrystal LiMn_(0. 6)Fe_(0. 4)PO_4 cathode material was obtained via hydrothermal method at 180℃ for 10 h without any surfactant. The effects of hydrothermal time on the phase and morphology of the material were discussed.By controlling the reaction solutions, the rodlike, flowerlike,and strawlike LiMn_(0.6)Fe_(0.4)PO_4 cathode materials were synthesized. Electrochemical performances show that the rodlike LiMn_(0. 6)Fe_(0. 4)PO_4 has the best electrochemical properties. The initial discharge capacity of the rodlike structure is 106.4 mAh·g^(-1), which is higher than those of flowerlike and strawlike materials.
基金financially supported by the National High-Tech Research and Development(863) Program of China(No.2006AA11A160)the National Natural Science Foundation of China(No.50604018)
文摘LiMn2O4 spinel cathode materials were modified with 2 wt.%Li-M-PO4（M=Co,Ni,Mn） by polyol synthesis method.The phosphate surface-modified LiMn2O4 cathode materials were physically characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM） and energy dispersive X-ray spectroscopy（EDS）.The charge-discharge test showed that the cycling and rate capacities of LiMn2O4 cathode materials were significantly enhanced by stabilizing the electrode surface with phosphate.
基金FundedbytheNationalNaturalScienceFoundationofChi na (No .5 9972 0 2 7)
文摘Normal spinel LiMn 2O 4 was synthesized by sol-gel method using lithium nitrate,manganese nitrate,citric acid and ethylene glycol as raw materials. LiMn 2O 4 was characterized by XRD,TG-DTA,IR,SEM and AAS.The optimum conditions for the synthesis were explored.Citric acid and ethylene glycol were mixed with molar ratio of 0.25,and the mixture was esterified at 140℃ for 4 hours.Then lithium nitrate and manganese nitrate were added with molar ratio of 0.6. In the system,the total molar of cations was equal to that of citric acid. At last, reflux the system at 105℃ for 2 hours. Dried gel was fired at 600℃ for 8 hours. Particle diameters of raw product were about 100 nm mainly. Further research shows that lithium ion of LiMn 2O 4 is easy to be extracted,and normal spinel λ-MnO 2 can be obtained after lithium ion extraction.
基金the National Natural Science Foundation of China (No.91645201, No.21873019 and No.21573044).
文摘Using the highly accurate G4 method, we computed the thermodynamic data of 1287 possible reaction products under a wide range of reaction conditions in the Fischer-Tropcsh synthesis (FTS) process. These accurate thermodynamic data provide basic thermodynamic quantities for the actual chemical engineering process and are useful in analyzing product distribution because FTS demonstrates many features of an equilibrium-controlled system. Our results show that the number of thermodynamically allowed products to increase when lowering temperature, raising pressure, and raising H2/CO ratio. At low temperature, high pressure and high H2/CO ratio, many products are thermodynamically allowed and the selectivity of product has to be controlled by kinetic factors. On the other hand, high selectivity of lighter products can be realized in thermodynamics by raising temperature and lowering pressure. We found that the equilibrium product yield will reach a maximum and remain unchanged when lowering temperature, raising pressure, and raising H2/CO ratio to some limits, implying that optimizing reaction conditions has no effect on equilibrium product yields beyond these limits. The thermodynamic analysis is also useful in designing and evaluating FTS reaction mechanisms. We found that reaction pathways through formaldehyde should be discarded because of its extremely low equilibrium yield. Recently, in the FTS process using metal-oxide-zeolite catalysts for the highly selective production of C2-C4 olefins and aromatic hydrocarbons, there are several guesses on the possible reaction intermediates entering the zeolite channel. Our results show that ketene, methanol, and dimethyl ether are three possible reaction intermediates.
基金financially supported by the National Natural Science Foundation of China(No.50774103)
文摘Spinel-type lithium and titanium composite oxide Li4TisO12 was successfully synthesized via a novel hydrolysis method followed by calcination using titanium tetrachloride （TIC14） and lithium hydroxide （LiOH.H2O） as raw materials. Three major factors, including LiOH con- centration, LiOH dosage, and hydrolysis temperature were studied for optimizing the synthetic conditions to obtain a phase-pure Li4Ti5012. The physical and electrochemical properties of samples were characterized by X-ray dif- fraction （XRD）, thermogravimetric analysis （TGA）, fourier transform infrared spectroscopy （FT-IR）, scanning electron microscopy （SEM）, and constant current discharge-charge test. The FT-IR results indicate the presence of [TiO6] octahedra. The SEM images show that the Li4Ti5O12 pre- cursor obtained is an amorphous solid with an irregular and rough morphology. It is revealed that the phase-pure spinel Li4Ti5O12 powders with well crystallization and regular morphology can be obtained by calcining the precursor at 800 ℃ for 6 h. The constant current discharge-charge tests indicate that the Li4TisO12 material delivers an excellent cycling ability, maintaining 93.8 % of its initial specific capacity after 60 cycles at a current density of 0.5C.
基金financial support by the National Natural Science Foundation of China(No.52102241)Doctor of Suzhou University Scientific Research Foundation(Nos.2022BSK019,2020BS015)+2 种基金the Primary Research and Development Program of Anhui Province(No.201904a05020087)the Natural Science Research Project in Universities of Anhui Province in China(Nos.2022AH051386,KJ2021A1114)the Foundation(No.GZKF202211)of State Key Laboratory of Biobased Material and Green Papermaking Qilu University of Technology。
文摘Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to their exceptional hydrogen binding energy,exhibit remarkable catalytic activity and long-term stability in the hydrogen evolution reaction(HER).However,the restricted accessibility and exorbitant cost of noble-metal materials pose obstacles to their extensive adoption in industrial contexts.This review investigates strategies aimed at reducing the dependence on noble-metal electrocatalysts and developing a cost-effective alkaline HER catalyst,while considering the principles of sustainable development.The initial discussion covers the fundamental principle of HER,followed by an overview of prevalent techniques for synthesizing catalysts based on noble metals,along with a thorough examination of recent advancements.The subsequent discussion focuses on the strategies employed to improve noble metalbased catalysts,including enhancing the intrinsic activity at active sites and increasing the quantity of active sites.Ultimately,this investigation concludes by examining the present state and future direction of research in the field of electrocatalysis for the HER.
基金supported by National Natural Science Foundation of China(Grant Nos.52302293 and 22272110)Innovation Project of Education Department of Guangdong Province(Grant No.2023KTSCX124)+2 种基金Shenzhen Science and Technology Program(Grant No.KJZD2023092311460401)Guangdong Higher Education Letter(Grant No.[2024]No.30)Shenzhen Key Laboratory of Applied Technologies of Super-Diamond and Functional Crystals(Grant No.ZDSYS20230626091303007).
文摘With the boom in electric vehicles(EVs),there is an increasing demand for high-performance lithium-ion batteries.Lithium manganese iron phosphate(LMFP)has emerged as an enhanced variation of LiFePO4(LFP),offering an energy density 10%–20%greater than that of LFP.Structural distortion caused by the Jahn–Teller effect decreases the capacity and voltage platform,thus restricting the commercialization of this material.Herein,ideas to overcome these challenges,including the crystal structure of LMFP and strategies to mitigate the Jahn–Teller distortion,are first explored.Then,the migration pathways of Li+during charging and discharging and the phase transition mechanisms that affect the material’s performance are discussed.Next,the optimal Mn:Fe ratio for achieving the desired performance is described.The influences of various synthesis and modification methods on the morphology and structure of LMFP are reviewed.Additionally,different modification techniques,such as doping and coating,to enhance the performance of LMFP are highlighted.Finally,an overview of the current state of research on the recycling and reuse of LMFP is provided.By addressing these key topics,this paper offers a theoretical foundation for the further development of LMFP,thus contributing to its eventual commercialization.
基金supported by the National Natural Science Foundation of China(No.52072217)the National Key Research and Development Program of China(No.2022YFB3807700)+2 种基金the Joint Funds of the Hubei Natural Science Foundation Innovation and Development(No.2022CFD034)Hubei Natural Science Foundation Innovation Group Project(No.2022CFA020)the Major Technological Innovation Project of Hubei Science and Technology Department(No.2019AAA164).
文摘With the rapid development of new energy and the high proportion of new energy connected to the grid,energy storage has become the leading technology driving significant adjustments in the global energy landscape.Electrochemical energy storage,as the most popular and promising energy storage method,has received extensive attention.Currently,the most widely used energy storage method is metal-ion secondary batteries,whose performance mainly depends on the cathode material.Prussian blue analogues(PBAs)have a unique open framework structures that allow quick and reversible insertion/extraction of metal ions such as Na^(+),K^(+),Zn^(2+),Li^(+)etc.,thus attracting widespread attention.The advantages of simple synthesis process,abundant resources,and low cost also distinguish it from its counterparts.Unfortunately,the crystal water and structural defects in the PBAs lattice that is generated during the synthesis process,as well as the low Na content,significantly affect their electrochemical performance.This paper focuses on PBAs’synthesis methods,crystal structure,modification strategies,and their potential applications as cathode materials for various metal ion secondary batteries and looks forward to their future development direction.
