Sodium-ion batteries(SIBs)are considered as one of the most fascinating alternatives to lithium-ion batteries for grid-scale energy storage applications because of the low cost and wide abundance of sodium resources.A...Sodium-ion batteries(SIBs)are considered as one of the most fascinating alternatives to lithium-ion batteries for grid-scale energy storage applications because of the low cost and wide abundance of sodium resources.Among various cathode materials,mixed polyanion compounds come into the spotlight as promising electrode materials due to their superior electrochemical properties,such as high working voltage,long cycling stability,and facile reaction kinetics.In this review,we summarize the recent development in the exploration of different mixed polyanion cathode materials for SIBs.We provide a comprehensive understanding of the structure-composition-performance relationship of mixed polyanion cathode materials together with the discussion of their sodium storage mechanisms.It is anticipated that further innovative works on the material design of advanced cathode materials for batteries can be inspired.展开更多
Highly ordered and uniformly porous structure of conductive foams is a vital issue for various functional purposes such as piezoresistive sensing and electromagnetic interference(EMI) shielding. With the aids of Kevla...Highly ordered and uniformly porous structure of conductive foams is a vital issue for various functional purposes such as piezoresistive sensing and electromagnetic interference(EMI) shielding. With the aids of Kevlar polyanionic chains, thermoplastic polyurethane(TPU) foams reinforced by aramid nanofibers(ANF) with adjustable pore-size distribution were successfully obtained via a nonsolvent-induced phase separation. In this regard, the most outstanding result is the in situ formation of ANF in TPU foams after protonation of Kevlar polyanion during the NIPS process. Furthermore, in situ growth of copper nanoparticles(Cu NPs) on TPU/ANF foams was performed according to the electroless deposition by using the tiny amount of pre-blended Ti_(3)C_(2)T_(x) MXene as reducing agents. Particularly, the existence of Cu NPs layers significantly promoted the storage modulus in 2,932% increments, and the well-designed TPU/ANF/Ti_(3)C_(2)T_(x) MXene(PAM-Cu) composite foams showed distinguished compressive cycle stability. Taking virtues of the highly ordered and elastic porous architectures, the PAM-Cu foams were utilized as piezoresistive sensor exhibiting board compressive interval of 0–344.5 kPa(50% strain) with good sensitivity at 0.46 kPa^(-1). Meanwhile,the PAM-Cu foams displayed remarkable EMI shielding effectiveness at 79.09 dB in X band. This work provides an ideal strategy to fabricate highly ordered TPU foams with outstanding elastic recovery and excellent EMI shielding performance, which can be used as a promising candidate in integration of satisfactory piezoresistive sensor and EMI shielding applications for human–machine interfaces.展开更多
Sodium ion batteries(SIBs)have been regarded as one of the alternatives to lithium ion batteries owing to their wide availability and significantly low cost of sodium sources.However,they face serious challenges of lo...Sodium ion batteries(SIBs)have been regarded as one of the alternatives to lithium ion batteries owing to their wide availability and significantly low cost of sodium sources.However,they face serious challenges of low energy&power density and short cycling lifespan owing to the heavy mass and large radius of Na^(+).Vanadium-based polyanionic compounds have advantageous characteristic of high operating voltage,high ionic conductivity and robust structural framework,which is conducive to their high energy&power density and long lifespan for SIBs.In this review,we will overview the latest V-based polyanionic compounds,along with the respective characteristic from the intrinsic crystal structure to performance presentation and improvement for SIBs.One of the most important aspect is to discover the essential problems existed in the present V-based polyanionic compounds for high-energy&power applications,and point out most suitable solutions from the crystal structure modulation,interface tailoring and electrode configuration design.Moreover,some scientific issues of V-based polyanionic compounds shall be also proposed and related future direction shall be provided.We believe that this review can serve as a motivation for further development of novel V-based polyanionic compounds and drive them toward high energy&power applications in the near future.展开更多
Mixing polyanion cathode materials are promising candidates for the development of next-generation batteries, owing to their structural robustness and low-volume changes, yet low conductivity of polyanion hinders thei...Mixing polyanion cathode materials are promising candidates for the development of next-generation batteries, owing to their structural robustness and low-volume changes, yet low conductivity of polyanion hinders their practical capacity. Herein, the anion-site regulation is proposed to elevate the electrode kinetics and properties of polyanionic cathode. Multivalent anion P_(2)O_(7)^(4-) is selected to substitute the PO_(4)^(3-) in Na_(3)V_(2)(PO_(4))_(3) (NVP) lattice and regulate the ratio of polyanion groups to prepare Na_(3+x)V_(2)(PO_(4))_(3-x)(P_(2)O_(7))_(x)(NVPP_(x), 0 ≤ x ≤ 0.15) materials.The optimal Na_(3.1)V_(2)(PO_(4))_(2.9)(P_(2)O_(7))_(0.1) (NVPP_(0.1)) material can deliver remarkably elevated specific capacity(104 mAh g^(-1) at 0.1 C, 60 mAh g^(-1) at 20 C, respectively), which is higher than those of NVP. Moreover, NVPP_(0.1) exhibits outstanding cyclic stability(91% capacity retention after 300 cycles at 1 C). Experimental analyses reveal that the regulation of anions improves the structure stability, increases the active Na occupancy in the lattice and accelerates the Na+migration kinetics. The strategy of anion-site regulation provides the researchers a reference for the design of new high-performance polyanionic materials.展开更多
Doping modification of electrode materials is a sought-after strategy to improve their electrochemical performance in the secondary batteries field. Herein,polyanion（BO3）^3-doped Li3V2（PO4）3 cathode materials were...Doping modification of electrode materials is a sought-after strategy to improve their electrochemical performance in the secondary batteries field. Herein,polyanion（BO3）^3-doped Li3V2（PO4）3 cathode materials were successfully synthesized via a wet coordination method. The effects of（BO3）^3- doping content on crystal structure, morphology and electrochemical performance were explored by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS）. All the asprepared samples have the same monoclinic structure;among them, Li3V2（PO4）（2.75）（BO3）（0.15） sample has relatively uniform and optimized particle size. In addition, this sample has the highest discharge capacity and the best cycling stability, with an initial discharge capacity of 120.4mAh·g^-1, and after 30 cycles at a rate of 0.1C, the discharge capacity still remains 119.3 mAh·g^-1. It is confirmed that moderate polyanion（BO3）^3- doping can rearrange the electronic structure of the bulk Li3V2（PO4）3,lower the charge transfer resistance and further improve the electrochemical behaviors.展开更多
The optimized geometries at the RHF/6-311++G** level, the relatively stable energy at the MPW1PW91/6-311++G** level and the structural characters of anions have been acquired, indicating the stability is related to ...The optimized geometries at the RHF/6-311++G** level, the relatively stable energy at the MPW1PW91/6-311++G** level and the structural characters of anions have been acquired, indicating the stability is related to the chemical bonding of μ2?P atoms and the distri- bution of negative charges. The configurations of cage units P8 4- and P9 5- are stable due to the less torsion, but their ES values are relatively higher than that of P7 3- with more μ2?P atoms and the isolated stability is lower than that of P7 . They potentially play an important role as intermediate 3- in chemical reaction of producing complicated polyphosphides. Based on the related electronic properties, a stable polyanion must have low valence electron concentration, no (μ2?P)?(μ2?P) bond and a little dispersive charge. The earmark IR frequencies of cage units have been assigned to the vibration models in the end.展开更多
Aqueous Zn-ion energy storage systems,which are expected to be integrated into intelligent electronics as a secure power supply,suffer poor reversibility of Zn anodes,predominantly associated with dendritic growth and...Aqueous Zn-ion energy storage systems,which are expected to be integrated into intelligent electronics as a secure power supply,suffer poor reversibility of Zn anodes,predominantly associated with dendritic growth and side reactions.This study introduces a polyanionic strategy to address these formidable issues by developing a hydrogel electrolyte(PACXHE)with carboxyl groups.Notably,the carboxyl groups within the hydrogel structure establish favorable channels to promote the transport of Zn^(2+)ions.They also expedite the desolvation of hydrated Zn^(2+)ions,leading to enhanced deposition kinetics.Additionally,these functional groups confine interfacial planar diffusion and promote preferential deposition along the(002)plane of Zn,enabling a smooth surface texture of the Zn anode.This multifaceted regulation successfully achieves the suppression of Zn dendrites and side reactions,thereby enhancing the electrochemical reversibility and service life during plating/stripping cycles.Therefore,such an electrolyte demonstrates a high average Coulombic efficiency of 97.7%for 500 cycles in the Zn‖Cu cell and exceptional cyclability with a duration of 480 h at 1 mA cm^(-2)/1 mA h cm^(-2)in the Zn‖Zn cell.Beyond that,the Zn-ion hybrid micro-capacitor employing PACXHE exhibits satisfactory cycling stability,energy density,and practicality for energy storage in flexible,intelligent electronics.The present polyanionic-based hydrogel strategy and the development of PACXHE represent significant advancements in the design of hydrogel electrolytes,paving the way for a more sustainable and efficient future in the energy storage field.展开更多
Polyanion-based materials are considered one of the most attractive and promising cathode materials for lithiumion batteries(LIBs)due to their good stability,safety,cost-effectiveness,suitable voltages,and minimal env...Polyanion-based materials are considered one of the most attractive and promising cathode materials for lithiumion batteries(LIBs)due to their good stability,safety,cost-effectiveness,suitable voltages,and minimal environmental impact.However,these materials suffer from poor rate capability and low-temperature performance owing to limited electronic and ionic conductivity,which restricts their practical applicability.Recent developments,such as coating material particles with carbon or a conductive polymer,crystal deformation through the doping of foreign metal ions,and the production of nanostructured materials,have significantly enhanced the electrochemical performances of these materials.The successful applications of polyanion-based materials,especially in lithium-ion batteries,have been extensively reported.This comprehensive review discusses the current progress in crystal deformation in polyanion-based cathode materials,including phosphates,fluorophosphates,pyrophosphates,borates,silicates,sulfates,fluorosilicates,and oxalates.Therefore,this review provides detailed discussions on their synthesis strategies,electrochemical performance,and the doping of various ions.展开更多
In this research, the absorbance and luminescence response of two osmium(II) phenathrane (phen) carbonyl complexes to various DNA, heparin and i-carrageenan polyanions were studied. The [Os(phen)<sub>2</sub&g...In this research, the absorbance and luminescence response of two osmium(II) phenathrane (phen) carbonyl complexes to various DNA, heparin and i-carrageenan polyanions were studied. The [Os(phen)<sub>2</sub>CO(L)]<sup>2+</sup> complexes with L either a 4-phenyl pyridine (4-phpy) or phenyl imidazole (phimd) group exhibit moderate luminescent intensity in the visible region, their intensities are highly altered by the addition of DNA and other polyanion samples. These luminescent responses to polyanions were also compared with the [Ru(phen)<sub>3</sub>]<sup>2+</sup> complex. In ethanol solution, the presence of polyanions significantly enhanced the luminescent emission intensity of [Os(phen)<sub>2</sub>CO(L)]<sup>2+</sup> complexes with a blue shift. While the polyanions all showed emission enhancement on the highly lumi-nescent [Ru(phen)<sub>3</sub>]<sup>2+</sup> complex in ethanol solution with a red spectra shift. The [Os(phen)<sub>2</sub>CO(L)] <sup>2+</sup> with (phimd) ligand has the lowest emission in ethanol solution, its intensity can be enhanced up to 11 times in the presence of DNA polyanions. This enhancement for all the complexes in ethanol is mainly due to their electrostatic interaction with the anion sites and with some degree of ligand intercalation into the polyanion hydrophobic structure which reduced the solvent quenching of the complexes. The blue shift of the (4-phpy) and particularly (phimd) Os(II)CO complexes indicate an insertion of the (4-phpy) or (phimd) group into the polymer chains. The two new Os(II)CO complexes has great potential to be used as luminescence sensors for DNA and polyanion detection in the low micro molar range with high sensitivity.展开更多
The direct transformation of C-H to C-N bonds is a significant conversion for organic synthesis,pharmaceutical,and fine-chemical industries.It is imperative to explore economical and environmentally friendly catalytic...The direct transformation of C-H to C-N bonds is a significant conversion for organic synthesis,pharmaceutical,and fine-chemical industries.It is imperative to explore economical and environmentally friendly catalytic systems that focus on reusable catalysts,waste reduction,and mild conditions.Herein,we present an efficient and eco-friendly method for promoting the direct conversion of C-H to C-N bonds in water under visible light irradiation using a Ce(Ⅲ)-containing antimonotungstate photocatalyst,[(CH_(3))_(2)NH_(2)]_(4)Na_(21){[Ce_(4)(H_(2)O)_(8)W_(6)O_(12)(tar)_(3)(OAc)][B-α-SbW_(9)O_(33)]_(4)}·51H_(2)O(CeSbW,H_(4)tar=tartaric acid,HOAc=acetic acid).CeSbW exhibits excellent photoelectric activity with a unique intramolecular charge transfer from Ce^(Ⅲ) to POM(W^(Ⅵ))upon visible light irradiation.With CeSbW as the photocatalyst,the visible-light-induced C-N bond formation via hydroacylation of dialkyl azodicarboxylates was successfully achieved,featuring broad substrate scope,excellent reusability,and environmentally benign reaction conditions.This methodology not only enriches the synthesis strategies for visible-light-responsive POM catalysts but also provides an efficient and sustainable photocatalytic system for C-N bond construction.展开更多
Two new yttrium sulfate tellurites,namely,Y_(3)(TeO_(3))_(2)(SO_(4))_(2)(OH)(H_(2)O)and Y_(2)(Te_(4)O_(10))(SO_(4)),were achieved in our exploration of new sulfate tellurites,with a large birefringence in the Y^(3+)–...Two new yttrium sulfate tellurites,namely,Y_(3)(TeO_(3))_(2)(SO_(4))_(2)(OH)(H_(2)O)and Y_(2)(Te_(4)O_(10))(SO_(4)),were achieved in our exploration of new sulfate tellurites,with a large birefringence in the Y^(3+)–Te^(4+)–SO_(4)^(2−)system.The two compounds exhibit two new three dimensional(3D)frameworks composed of different yttrium tellurite layers bridged by sulfate tetrahedra.展开更多
Mixed polyanionic compounds are potential cathode materials for sodium-ion batteries(SIBs).Herein,considering the advantages of the strong inductive effect of sulfate and the diverse,flexible coordination modes of oxa...Mixed polyanionic compounds are potential cathode materials for sodium-ion batteries(SIBs).Herein,considering the advantages of the strong inductive effect of sulfate and the diverse,flexible coordination modes of oxalate,we systematically explored mixed sulfate-oxalate systems and obtained three sodium-contained polyanionic compounds.Interestingly,the novel three-dimensional Na_(2)Co(C(2)O_(4))(SO_(4))·xH_(2)O(x=1-1.5)was found to be a promising cathode material for SIBs with good electrochemical activity at high voltage.The present study sets an example of exploring sodium-storage materials in the mixed polyanionic family and provides new insights into designing novel high-voltage cathodes for sodium-based energy storage devices.展开更多
Integrated rocksalt-polyanion cathodes(DRXPS)are promising candidates for next-generation lithium-ion battery cathode materials that combine high energy density,stable cycling performance,and reduced reliance on Co an...Integrated rocksalt-polyanion cathodes(DRXPS)are promising candidates for next-generation lithium-ion battery cathode materials that combine high energy density,stable cycling performance,and reduced reliance on Co and Ni.In this work,we investigated Li_(3)Mn_(1.6)P_(0.4)O_(5.4)F_(0.6),a new DRXPS cathode with fluoride incorporation.A pure spinel phase was formed and a discharge capacity retention of 84%was achieved after 200 cycles between 1.5 and 4.8 V versus Li/Li^(+).In comparison,the similarly synthesized Li_(3)Mn_(1.6)Nb_(0.4)O_(5.4)F_(0.6),in which all P^(5+)was substituted by Nb^(5+)while maintaining the same stoichiometry for all other elements,crystallized in a disordered rocksalt structure,and exhibited inferior capacity retention and rate capability than the P^(5+)counterpart.Our findings expand the compositional space of DRXPS to include F^(−),justify the viability of integrating polyanion groups in rocksalt-type cathodes,and highlight the superiority of P^(5+)as a cation charge compensator compared to the commonly used Nb^(5+).This work thereby advances the design of robust,high-performance cathode materials for sustainable batteries.展开更多
NASICON-type Na_(3)V_(2)(PO_(4))_(3)(NVP)materials are seen as highly promising cathode materials in the field of sodium-ion batteries due to their low cost,a solid three-dimensional skeleton and good theoretical capa...NASICON-type Na_(3)V_(2)(PO_(4))_(3)(NVP)materials are seen as highly promising cathode materials in the field of sodium-ion batteries due to their low cost,a solid three-dimensional skeleton and good theoretical capacity,as well as high ionic conductivity.Nevertheless,the problem of low intrinsic electronic conductivity and energy density has limited the practical application of the materials.To address this issue,the relevant research team has successfully achieved remarkable research results through unremitting exploration and practical innovation.In this work,the crystal structure,ion migration mechanism and sodium storage mechanism of NVP cathode materials are systematically reviewed,with a focus on summarizing the latest progress of V-site doping modification research,classifying and exploring V-site doping from the perspectives of electronic structure,lattice strain and entropy,and briefly describing the optimization mechanism of V-site doping on electrochemical performance.In addition,the challenges and prospects for the future development of NVP cathode materials are presented,which are believed to provide new thinking for the design and development of high-performance NVP cathode materials and contribute to the large-scale application of sodium-ion batteries.展开更多
In recent years,rechargeable lithium-ion batteries(LIBs)have become widely used in everyday applications such as portable electronic devices,electric vehicles and energy storage systems.Despite this,the electrochemica...In recent years,rechargeable lithium-ion batteries(LIBs)have become widely used in everyday applications such as portable electronic devices,electric vehicles and energy storage systems.Despite this,the electrochemical performance of LIBs cannot meet the energy demands of rapidly growing technological evolutions.And although significant progress has been made in the development of corresponding anodes based primarily on carbon,oxide and silicon materials,these materials still possess shortcomings in current LIB applications.For example,graphite exhibits safety concerns due to an operating potential close to that of lithium(Li)metal plating whereas Li4Ti5O12 possesses low energy density for high operation potential and silicon experiences limited cyclability for large volume expansion during charging/discharging.Alternatively,polyanionic compounds such as(PO_(4))^(3–),(SiO_(4))^(4–),(SO_(4))^(2–)and(BO_(3))^(3−)as electrode materials have gained increasing attention in recent years due to their ability to stabilize structures,adjust redox couples and provide migration channels for"vip"ions,resulting in corresponding electrode materials with long-term cycling,high energy density and outstanding rate capability.Based on these advantages and combined with recent findings in terms of silicate anodes,this review will summarize the recent progress in the development of polyanion-based anode materials for LIBs and sodium-ion batteries.Furthermore,this review will present our latest research based on polyanion groups such as(GeO_(4))^(4–)to compensate for the lack of available studies and to provide our perspective on these materials.展开更多
A new organic cathode namely potassium 2,6-dihydroxyanthraquinone(AQ26OK,theoretical capacity(CT)=169 mA h g^(-1))is synthesized and fully characterized for Kion batteries.AQ26OK is called polyanionic organic cathode ...A new organic cathode namely potassium 2,6-dihydroxyanthraquinone(AQ26OK,theoretical capacity(CT)=169 mA h g^(-1))is synthesized and fully characterized for Kion batteries.AQ26OK is called polyanionic organic cathode because it has a polyanionic organic skeleton(-2 valent)and two strong ionic K-O bonds.Consequently,the polyanionic AQ26OK is hardly soluble into most organic liquid electrolytes.In half cells(0.3-3.4 V vs.K^(+)/K)using 1 mol L^(-1) KPF6 in dimethoxyethane,AQ26OK delivers a highly stable specific capacity of 201 mA h g^(-1)@50 mA g^(-1) over 450 cycles(4-month test)and realizes~106 mA h g^(-1) for 3200 cycles at 500 mA g^(-1).Using the reduced state(K4TP)of potassium terephthalate(K2TP)as the organic anode,the resulting K4TP Ⅱ AQ26OK organic potassium-ion batteries can display a highly stable average discharge capacity of 135 mA h g^(-1) cathodeover 250 cycles at 100 mA g^(-1) and~47 mA h g^(-1) for 1000 cycles at 500 mA g^(-1) during the working voltage of 0.01-3.1 V.To the best of our knowledge,AQ26OK is among the best stable cathodes reported for K-ion batteries.展开更多
Zinc-ion hybrid supercapacitors(ZHSCs)have been widely considered as promising candidates for flexible electrochemical energy storage devices.The key challenge is to develop hydrogel electrolytes with high hydrophilic...Zinc-ion hybrid supercapacitors(ZHSCs)have been widely considered as promising candidates for flexible electrochemical energy storage devices.The key challenge is to develop hydrogel electrolytes with high hydrophilicity,anti-freezing,bending resistance,and stable interface with electrodes.This study reported a hydrogel electrolyte system that can meet the above functions,in which the zincophilic and negatively charged SO_(3)^(−),migratable Na^(+),abundant hydrophilic functional groups,gum xanthan,and porous architecture could effectively promote the electrochemical performance of ZHSCs.ZHSCs with such hydrogel electrolytes not only exhibited good low-temperature performance but also showed excellent bending resistance ability.A high specific capacitance could be kept after a long air-working lifespan over 10,000 cycles under a wide operation voltage of 1.85 V at−10℃.Furthermore,flexible ZHSCs could maintain the capacitance retention of 93.18%even after continuous 500 bends at an angle of 180°.The designed hydrogel electrolytes could be also used for other electrochemical energy storage devices with anti-freezing and bending resistance by changing electrolyte salt.展开更多
基金financial support by the National Science Foundation of China(Nos.21673165 and 21972108)the National Key Research Program of China(No.2016YFB0901500)the supercomputing system in the Supercomputing Center of Wuhan University。
文摘Sodium-ion batteries(SIBs)are considered as one of the most fascinating alternatives to lithium-ion batteries for grid-scale energy storage applications because of the low cost and wide abundance of sodium resources.Among various cathode materials,mixed polyanion compounds come into the spotlight as promising electrode materials due to their superior electrochemical properties,such as high working voltage,long cycling stability,and facile reaction kinetics.In this review,we summarize the recent development in the exploration of different mixed polyanion cathode materials for SIBs.We provide a comprehensive understanding of the structure-composition-performance relationship of mixed polyanion cathode materials together with the discussion of their sodium storage mechanisms.It is anticipated that further innovative works on the material design of advanced cathode materials for batteries can be inspired.
基金financially sponsored by the Science and Technology Commission of Shanghai Municipality (20230742300 and 18595800700)Key Laboratory of Resource Chemistry, Ministry of Education (KLRC_ME2103)the project of “joint assignment” in Shanghai University led by Prof. Tongyue Gao from School of Mechatronic Engineering and Automation。
文摘Highly ordered and uniformly porous structure of conductive foams is a vital issue for various functional purposes such as piezoresistive sensing and electromagnetic interference(EMI) shielding. With the aids of Kevlar polyanionic chains, thermoplastic polyurethane(TPU) foams reinforced by aramid nanofibers(ANF) with adjustable pore-size distribution were successfully obtained via a nonsolvent-induced phase separation. In this regard, the most outstanding result is the in situ formation of ANF in TPU foams after protonation of Kevlar polyanion during the NIPS process. Furthermore, in situ growth of copper nanoparticles(Cu NPs) on TPU/ANF foams was performed according to the electroless deposition by using the tiny amount of pre-blended Ti_(3)C_(2)T_(x) MXene as reducing agents. Particularly, the existence of Cu NPs layers significantly promoted the storage modulus in 2,932% increments, and the well-designed TPU/ANF/Ti_(3)C_(2)T_(x) MXene(PAM-Cu) composite foams showed distinguished compressive cycle stability. Taking virtues of the highly ordered and elastic porous architectures, the PAM-Cu foams were utilized as piezoresistive sensor exhibiting board compressive interval of 0–344.5 kPa(50% strain) with good sensitivity at 0.46 kPa^(-1). Meanwhile,the PAM-Cu foams displayed remarkable EMI shielding effectiveness at 79.09 dB in X band. This work provides an ideal strategy to fabricate highly ordered TPU foams with outstanding elastic recovery and excellent EMI shielding performance, which can be used as a promising candidate in integration of satisfactory piezoresistive sensor and EMI shielding applications for human–machine interfaces.
基金financial support from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA21070500)the DNL Cooperation Fund,CAS(DNL201914)。
文摘Sodium ion batteries(SIBs)have been regarded as one of the alternatives to lithium ion batteries owing to their wide availability and significantly low cost of sodium sources.However,they face serious challenges of low energy&power density and short cycling lifespan owing to the heavy mass and large radius of Na^(+).Vanadium-based polyanionic compounds have advantageous characteristic of high operating voltage,high ionic conductivity and robust structural framework,which is conducive to their high energy&power density and long lifespan for SIBs.In this review,we will overview the latest V-based polyanionic compounds,along with the respective characteristic from the intrinsic crystal structure to performance presentation and improvement for SIBs.One of the most important aspect is to discover the essential problems existed in the present V-based polyanionic compounds for high-energy&power applications,and point out most suitable solutions from the crystal structure modulation,interface tailoring and electrode configuration design.Moreover,some scientific issues of V-based polyanionic compounds shall be also proposed and related future direction shall be provided.We believe that this review can serve as a motivation for further development of novel V-based polyanionic compounds and drive them toward high energy&power applications in the near future.
基金financially supported by the National Natural Science Foundation of China (No. 91963118)Science Technology Program of Jilin Province (No. 20200201066JC)+1 种基金“13th Five-Year” Science and Technology Research from the Education Department of Jilin Province (No.JJKH20201179KJ)the 111 Project (No. B13013)。
文摘Mixing polyanion cathode materials are promising candidates for the development of next-generation batteries, owing to their structural robustness and low-volume changes, yet low conductivity of polyanion hinders their practical capacity. Herein, the anion-site regulation is proposed to elevate the electrode kinetics and properties of polyanionic cathode. Multivalent anion P_(2)O_(7)^(4-) is selected to substitute the PO_(4)^(3-) in Na_(3)V_(2)(PO_(4))_(3) (NVP) lattice and regulate the ratio of polyanion groups to prepare Na_(3+x)V_(2)(PO_(4))_(3-x)(P_(2)O_(7))_(x)(NVPP_(x), 0 ≤ x ≤ 0.15) materials.The optimal Na_(3.1)V_(2)(PO_(4))_(2.9)(P_(2)O_(7))_(0.1) (NVPP_(0.1)) material can deliver remarkably elevated specific capacity(104 mAh g^(-1) at 0.1 C, 60 mAh g^(-1) at 20 C, respectively), which is higher than those of NVP. Moreover, NVPP_(0.1) exhibits outstanding cyclic stability(91% capacity retention after 300 cycles at 1 C). Experimental analyses reveal that the regulation of anions improves the structure stability, increases the active Na occupancy in the lattice and accelerates the Na+migration kinetics. The strategy of anion-site regulation provides the researchers a reference for the design of new high-performance polyanionic materials.
基金financially supported by the National Key Research and Development Program of China(No.2016YFB0100500)the Beijing Co-construction Project(No.20150939014)
文摘Doping modification of electrode materials is a sought-after strategy to improve their electrochemical performance in the secondary batteries field. Herein,polyanion（BO3）^3-doped Li3V2（PO4）3 cathode materials were successfully synthesized via a wet coordination method. The effects of（BO3）^3- doping content on crystal structure, morphology and electrochemical performance were explored by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS）. All the asprepared samples have the same monoclinic structure;among them, Li3V2（PO4）（2.75）（BO3）（0.15） sample has relatively uniform and optimized particle size. In addition, this sample has the highest discharge capacity and the best cycling stability, with an initial discharge capacity of 120.4mAh·g^-1, and after 30 cycles at a rate of 0.1C, the discharge capacity still remains 119.3 mAh·g^-1. It is confirmed that moderate polyanion（BO3）^3- doping can rearrange the electronic structure of the bulk Li3V2（PO4）3,lower the charge transfer resistance and further improve the electrochemical behaviors.
文摘The optimized geometries at the RHF/6-311++G** level, the relatively stable energy at the MPW1PW91/6-311++G** level and the structural characters of anions have been acquired, indicating the stability is related to the chemical bonding of μ2?P atoms and the distri- bution of negative charges. The configurations of cage units P8 4- and P9 5- are stable due to the less torsion, but their ES values are relatively higher than that of P7 3- with more μ2?P atoms and the isolated stability is lower than that of P7 . They potentially play an important role as intermediate 3- in chemical reaction of producing complicated polyphosphides. Based on the related electronic properties, a stable polyanion must have low valence electron concentration, no (μ2?P)?(μ2?P) bond and a little dispersive charge. The earmark IR frequencies of cage units have been assigned to the vibration models in the end.
基金funded by the National Natural Science Foundation of China(U2003216)the National Key Research and Development Program of China(2022YFB4101600)+1 种基金the Shanghai Cooperation Organisation Project(2022E01020)the Scientific Research Program of the Higher Education Institution of Xinjiang(XJEDU2022P004)。
文摘Aqueous Zn-ion energy storage systems,which are expected to be integrated into intelligent electronics as a secure power supply,suffer poor reversibility of Zn anodes,predominantly associated with dendritic growth and side reactions.This study introduces a polyanionic strategy to address these formidable issues by developing a hydrogel electrolyte(PACXHE)with carboxyl groups.Notably,the carboxyl groups within the hydrogel structure establish favorable channels to promote the transport of Zn^(2+)ions.They also expedite the desolvation of hydrated Zn^(2+)ions,leading to enhanced deposition kinetics.Additionally,these functional groups confine interfacial planar diffusion and promote preferential deposition along the(002)plane of Zn,enabling a smooth surface texture of the Zn anode.This multifaceted regulation successfully achieves the suppression of Zn dendrites and side reactions,thereby enhancing the electrochemical reversibility and service life during plating/stripping cycles.Therefore,such an electrolyte demonstrates a high average Coulombic efficiency of 97.7%for 500 cycles in the Zn‖Cu cell and exceptional cyclability with a duration of 480 h at 1 mA cm^(-2)/1 mA h cm^(-2)in the Zn‖Zn cell.Beyond that,the Zn-ion hybrid micro-capacitor employing PACXHE exhibits satisfactory cycling stability,energy density,and practicality for energy storage in flexible,intelligent electronics.The present polyanionic-based hydrogel strategy and the development of PACXHE represent significant advancements in the design of hydrogel electrolytes,paving the way for a more sustainable and efficient future in the energy storage field.
文摘Polyanion-based materials are considered one of the most attractive and promising cathode materials for lithiumion batteries(LIBs)due to their good stability,safety,cost-effectiveness,suitable voltages,and minimal environmental impact.However,these materials suffer from poor rate capability and low-temperature performance owing to limited electronic and ionic conductivity,which restricts their practical applicability.Recent developments,such as coating material particles with carbon or a conductive polymer,crystal deformation through the doping of foreign metal ions,and the production of nanostructured materials,have significantly enhanced the electrochemical performances of these materials.The successful applications of polyanion-based materials,especially in lithium-ion batteries,have been extensively reported.This comprehensive review discusses the current progress in crystal deformation in polyanion-based cathode materials,including phosphates,fluorophosphates,pyrophosphates,borates,silicates,sulfates,fluorosilicates,and oxalates.Therefore,this review provides detailed discussions on their synthesis strategies,electrochemical performance,and the doping of various ions.
文摘In this research, the absorbance and luminescence response of two osmium(II) phenathrane (phen) carbonyl complexes to various DNA, heparin and i-carrageenan polyanions were studied. The [Os(phen)<sub>2</sub>CO(L)]<sup>2+</sup> complexes with L either a 4-phenyl pyridine (4-phpy) or phenyl imidazole (phimd) group exhibit moderate luminescent intensity in the visible region, their intensities are highly altered by the addition of DNA and other polyanion samples. These luminescent responses to polyanions were also compared with the [Ru(phen)<sub>3</sub>]<sup>2+</sup> complex. In ethanol solution, the presence of polyanions significantly enhanced the luminescent emission intensity of [Os(phen)<sub>2</sub>CO(L)]<sup>2+</sup> complexes with a blue shift. While the polyanions all showed emission enhancement on the highly lumi-nescent [Ru(phen)<sub>3</sub>]<sup>2+</sup> complex in ethanol solution with a red spectra shift. The [Os(phen)<sub>2</sub>CO(L)] <sup>2+</sup> with (phimd) ligand has the lowest emission in ethanol solution, its intensity can be enhanced up to 11 times in the presence of DNA polyanions. This enhancement for all the complexes in ethanol is mainly due to their electrostatic interaction with the anion sites and with some degree of ligand intercalation into the polyanion hydrophobic structure which reduced the solvent quenching of the complexes. The blue shift of the (4-phpy) and particularly (phimd) Os(II)CO complexes indicate an insertion of the (4-phpy) or (phimd) group into the polymer chains. The two new Os(II)CO complexes has great potential to be used as luminescence sensors for DNA and polyanion detection in the low micro molar range with high sensitivity.
基金financially supported by the National Natural Science Foundation of China(22371040 and 22301033)the Jiangxi Provincial Natural Science Foundation(20232ACB213005 and 20242BAB25125)the Open Fund of Hubei Key Laboratory of Processing and Application of Catalytic Materials(202441804).
文摘The direct transformation of C-H to C-N bonds is a significant conversion for organic synthesis,pharmaceutical,and fine-chemical industries.It is imperative to explore economical and environmentally friendly catalytic systems that focus on reusable catalysts,waste reduction,and mild conditions.Herein,we present an efficient and eco-friendly method for promoting the direct conversion of C-H to C-N bonds in water under visible light irradiation using a Ce(Ⅲ)-containing antimonotungstate photocatalyst,[(CH_(3))_(2)NH_(2)]_(4)Na_(21){[Ce_(4)(H_(2)O)_(8)W_(6)O_(12)(tar)_(3)(OAc)][B-α-SbW_(9)O_(33)]_(4)}·51H_(2)O(CeSbW,H_(4)tar=tartaric acid,HOAc=acetic acid).CeSbW exhibits excellent photoelectric activity with a unique intramolecular charge transfer from Ce^(Ⅲ) to POM(W^(Ⅵ))upon visible light irradiation.With CeSbW as the photocatalyst,the visible-light-induced C-N bond formation via hydroacylation of dialkyl azodicarboxylates was successfully achieved,featuring broad substrate scope,excellent reusability,and environmentally benign reaction conditions.This methodology not only enriches the synthesis strategies for visible-light-responsive POM catalysts but also provides an efficient and sustainable photocatalytic system for C-N bond construction.
基金supported by the National Natural Science Foundation of China(Grant Nos:91963105,21773244,21875248,21921001 and 22031009)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No:XDB20000000)the NSF of Fujian Province(Grant No:2018J01025).
文摘Two new yttrium sulfate tellurites,namely,Y_(3)(TeO_(3))_(2)(SO_(4))_(2)(OH)(H_(2)O)and Y_(2)(Te_(4)O_(10))(SO_(4)),were achieved in our exploration of new sulfate tellurites,with a large birefringence in the Y^(3+)–Te^(4+)–SO_(4)^(2−)system.The two compounds exhibit two new three dimensional(3D)frameworks composed of different yttrium tellurite layers bridged by sulfate tetrahedra.
基金support from the National Key R&D Program of China(grant no.2022YFB2402600)the National Natural Science Foundation of China(grant nos.52125105,52061160484,52372250)+1 种基金the Shenzhen Science and Technology Planning Project(grant nos.RCYX20221008092850072,GJHZ20210705141407023,ZDSYS20210706144000003)the Guangdong Basic and Applied Basic Research Foundation(grant nos.2021A1515010184 and 2022A1515110031).
文摘Mixed polyanionic compounds are potential cathode materials for sodium-ion batteries(SIBs).Herein,considering the advantages of the strong inductive effect of sulfate and the diverse,flexible coordination modes of oxalate,we systematically explored mixed sulfate-oxalate systems and obtained three sodium-contained polyanionic compounds.Interestingly,the novel three-dimensional Na_(2)Co(C(2)O_(4))(SO_(4))·xH_(2)O(x=1-1.5)was found to be a promising cathode material for SIBs with good electrochemical activity at high voltage.The present study sets an example of exploring sodium-storage materials in the mixed polyanionic family and provides new insights into designing novel high-voltage cathodes for sodium-based energy storage devices.
基金sponsored by Tsinghua-Toyota Joint Research Fund.This study used resources of 18-ID and 23-ID-2 of the National Synchrotron Light Source II,a U.S.Department of Energy(DOE)Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No.DESC0012704.
文摘Integrated rocksalt-polyanion cathodes(DRXPS)are promising candidates for next-generation lithium-ion battery cathode materials that combine high energy density,stable cycling performance,and reduced reliance on Co and Ni.In this work,we investigated Li_(3)Mn_(1.6)P_(0.4)O_(5.4)F_(0.6),a new DRXPS cathode with fluoride incorporation.A pure spinel phase was formed and a discharge capacity retention of 84%was achieved after 200 cycles between 1.5 and 4.8 V versus Li/Li^(+).In comparison,the similarly synthesized Li_(3)Mn_(1.6)Nb_(0.4)O_(5.4)F_(0.6),in which all P^(5+)was substituted by Nb^(5+)while maintaining the same stoichiometry for all other elements,crystallized in a disordered rocksalt structure,and exhibited inferior capacity retention and rate capability than the P^(5+)counterpart.Our findings expand the compositional space of DRXPS to include F^(−),justify the viability of integrating polyanion groups in rocksalt-type cathodes,and highlight the superiority of P^(5+)as a cation charge compensator compared to the commonly used Nb^(5+).This work thereby advances the design of robust,high-performance cathode materials for sustainable batteries.
基金supported by the National Natural Science Foundation of China(no.52574348)the Natural Science Foundation of Hebei Province(no.B2024501004)+2 种基金the Fundamental Research Funds for the Central Universities(no.N2423013)the Shijiazhuang Basic Research Project(no.241790667A)the Performance Subsidy Fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(no.22567627H).
文摘NASICON-type Na_(3)V_(2)(PO_(4))_(3)(NVP)materials are seen as highly promising cathode materials in the field of sodium-ion batteries due to their low cost,a solid three-dimensional skeleton and good theoretical capacity,as well as high ionic conductivity.Nevertheless,the problem of low intrinsic electronic conductivity and energy density has limited the practical application of the materials.To address this issue,the relevant research team has successfully achieved remarkable research results through unremitting exploration and practical innovation.In this work,the crystal structure,ion migration mechanism and sodium storage mechanism of NVP cathode materials are systematically reviewed,with a focus on summarizing the latest progress of V-site doping modification research,classifying and exploring V-site doping from the perspectives of electronic structure,lattice strain and entropy,and briefly describing the optimization mechanism of V-site doping on electrochemical performance.In addition,the challenges and prospects for the future development of NVP cathode materials are presented,which are believed to provide new thinking for the design and development of high-performance NVP cathode materials and contribute to the large-scale application of sodium-ion batteries.
基金supported by the National Natural Science Foundation of China with Grant No.21875045 and 22005059the China Postdoctoral Science Foundation with Grant No.2019M661339.
文摘In recent years,rechargeable lithium-ion batteries(LIBs)have become widely used in everyday applications such as portable electronic devices,electric vehicles and energy storage systems.Despite this,the electrochemical performance of LIBs cannot meet the energy demands of rapidly growing technological evolutions.And although significant progress has been made in the development of corresponding anodes based primarily on carbon,oxide and silicon materials,these materials still possess shortcomings in current LIB applications.For example,graphite exhibits safety concerns due to an operating potential close to that of lithium(Li)metal plating whereas Li4Ti5O12 possesses low energy density for high operation potential and silicon experiences limited cyclability for large volume expansion during charging/discharging.Alternatively,polyanionic compounds such as(PO_(4))^(3–),(SiO_(4))^(4–),(SO_(4))^(2–)and(BO_(3))^(3−)as electrode materials have gained increasing attention in recent years due to their ability to stabilize structures,adjust redox couples and provide migration channels for"vip"ions,resulting in corresponding electrode materials with long-term cycling,high energy density and outstanding rate capability.Based on these advantages and combined with recent findings in terms of silicate anodes,this review will summarize the recent progress in the development of polyanion-based anode materials for LIBs and sodium-ion batteries.Furthermore,this review will present our latest research based on polyanion groups such as(GeO_(4))^(4–)to compensate for the lack of available studies and to provide our perspective on these materials.
基金supported by the Fundamental Research Funds of University of Electronic Science and Technology of China(UESTC,ZYGX2019J027)the Open Foundation of State Key Laboratory of Electronic Thin Films and Integrated Devices of UESTC(KFJJ201915)Sichuan Science and Technology Program(20YYJC3821)。
文摘A new organic cathode namely potassium 2,6-dihydroxyanthraquinone(AQ26OK,theoretical capacity(CT)=169 mA h g^(-1))is synthesized and fully characterized for Kion batteries.AQ26OK is called polyanionic organic cathode because it has a polyanionic organic skeleton(-2 valent)and two strong ionic K-O bonds.Consequently,the polyanionic AQ26OK is hardly soluble into most organic liquid electrolytes.In half cells(0.3-3.4 V vs.K^(+)/K)using 1 mol L^(-1) KPF6 in dimethoxyethane,AQ26OK delivers a highly stable specific capacity of 201 mA h g^(-1)@50 mA g^(-1) over 450 cycles(4-month test)and realizes~106 mA h g^(-1) for 3200 cycles at 500 mA g^(-1).Using the reduced state(K4TP)of potassium terephthalate(K2TP)as the organic anode,the resulting K4TP Ⅱ AQ26OK organic potassium-ion batteries can display a highly stable average discharge capacity of 135 mA h g^(-1) cathodeover 250 cycles at 100 mA g^(-1) and~47 mA h g^(-1) for 1000 cycles at 500 mA g^(-1) during the working voltage of 0.01-3.1 V.To the best of our knowledge,AQ26OK is among the best stable cathodes reported for K-ion batteries.
基金The financial support from National Natural Science Foundation of China(2210910352205489,and 21875144)Shenzhen Science and Technology Research Grant(JCYJ20200109105003940)is gratefully acknowledged.
文摘Zinc-ion hybrid supercapacitors(ZHSCs)have been widely considered as promising candidates for flexible electrochemical energy storage devices.The key challenge is to develop hydrogel electrolytes with high hydrophilicity,anti-freezing,bending resistance,and stable interface with electrodes.This study reported a hydrogel electrolyte system that can meet the above functions,in which the zincophilic and negatively charged SO_(3)^(−),migratable Na^(+),abundant hydrophilic functional groups,gum xanthan,and porous architecture could effectively promote the electrochemical performance of ZHSCs.ZHSCs with such hydrogel electrolytes not only exhibited good low-temperature performance but also showed excellent bending resistance ability.A high specific capacitance could be kept after a long air-working lifespan over 10,000 cycles under a wide operation voltage of 1.85 V at−10℃.Furthermore,flexible ZHSCs could maintain the capacitance retention of 93.18%even after continuous 500 bends at an angle of 180°.The designed hydrogel electrolytes could be also used for other electrochemical energy storage devices with anti-freezing and bending resistance by changing electrolyte salt.
