Although metal oxide compounds are considered as desirable anode materials for potassium-ion batteries(PIBs)due to their high theoretical capacity,the large volume variation remains a key issue in realizing metal oxid...Although metal oxide compounds are considered as desirable anode materials for potassium-ion batteries(PIBs)due to their high theoretical capacity,the large volume variation remains a key issue in realizing metal oxide anodes with long cycle life and excellent rate property.In this study,polypyrroleencapsulated Sb_(2)WO_(6)(denoted Sb_(2)WO_(6)@PPy)microflowers are synthesized by a one-step hydrothermal method followed by in-situ polymerization and coating by pyrrole.Leveraging the nanosheet-stacked Sb_(2)WO_(6)microflower structure,the improved electronic conductivity,and the architectural protection offered by the PPy coating,Sb_(2)WO_(6)@PPy exhibits boosted potassium storage properties,thereby demonstrating an outstanding rate property of 110.3 m A h g^(-1)at 5 A g^(-1)and delivering a long-period cycling stability with a reversible capacity of 197.2 m A h g^(-1)after 500 cycles at 1 A g^(-1).In addition,the conversion and alloying processes of Sb_(2)WO_(6)@PPy in PIBs with the generation of intermediates,K_(2)WO_(4)and K_(3)Sb,is determined by X-ray photoelectron spectroscopy,transmission electron microscopy,and exsitu X-ray diffraction during potassiation/depotassiation.Density functional theory calculations demonstrate that the robust coupling between PPy and Sb_(2)WO_(6)endues it with a much stronger total density of states and a built-in electric field,thereby increasing the electronic conductivity,and thus effectively reduces the K^(+)diffusion barrier.展开更多
Although chalcogenide anodes possess higher potassium storage capacity than intercalated-based graphite,their drastic volume change and the irreversible electrochemical reactions still hinder the effective electron/io...Although chalcogenide anodes possess higher potassium storage capacity than intercalated-based graphite,their drastic volume change and the irreversible electrochemical reactions still hinder the effective electron/ion transfer during the potassiation/depotassiation process.To solve the above problems,this article proposes the synthesis of a lamellar nanostructure where graphene nanosheets are embedded with SnSb_(2)Se_(4)nanoparticles(SnSb_(2)Se_(4)/GNS).In the product,fine monodisperse SnSb_(2)Se_(4)nanoparticles are coupled with graphene nanosheets to form a porous network framework,which can effectively mitigate the drastic volume changes during electrode reactions and guarantee efficient potassium-ion storage through the synergistic interactions among multiple elements.Various electrochemical analyses prove that SnSb_(2)Se_(4)inherits the advantages of the binary Sb2Se3 and SnSe while avoiding their disadvantages,confirming the synergistic effect of the ternary–chalcogenide system.When tested for potassium storage,the obtained composite delivers a high specific capacity of 368.5 mAh g^(-1)at 100 mA g^(-1)and a stable cycle performance of 265.8 mAh g^(-1)at 500 mA g^(-1)over 500 cycles.Additionally,the potassium iron hexacyanoferrate cathode and the SnSb_(2)Se_(4)/GNS anode are paired to fabricate the potassium-ion full cell,which shows excellent cyclic stability.In conclusion,this strategy employs atomic doping and interface interaction,which provides new insights for the design of high-rate electrode materials.展开更多
VS_(4) has a unique layered atomic chain structure and has the potential to become a high-performance cathode material of magnesium-ion batteries with a high capacity and long cycle life.However,low conductivity and s...VS_(4) has a unique layered atomic chain structure and has the potential to become a high-performance cathode material of magnesium-ion batteries with a high capacity and long cycle life.However,low conductivity and sluggish Mg^(2+)diffusivity during cycling limit its practical application in large-scale energy storage.Herein,a cooperative assembly-directed strategy is adopted to synthesize VS_(4) nanorods grown in situ on carbon nanotubes(CNTs/VS_(4)).VS_(4) nanorods are tightly anchored to CNTs through V-O-C interface covalent bonds,and CNTs can enhance the electronic conductivity of the nanocomposite.In addition,the ion insertion reaction using Mg^(2+)and Mg Cl^(+)as carriers reduces the polar barrier for divalent Mg^(2+)ion transport.This rationally designed architecture promotes ion diffusion and electron transfer,thus facilitating reaction kinetics.The cooperative assembly-oriented strategy can endow CNTs/VS_(4) with excellent magnesium storage properties,including a high reversible capacity of 223.2 m Ah g^(-1)at a current density of 50 m A g^(-1),a remarkable discharge capacity of 91.8 m Ah g^(-1)even at 2,000 m A g^(-1),and an impressive capacity retention of 85.2% after 1,000 cycles at 500 m A g^(-1).Moreover,this strategy can serve as a general synthetic method for the complexation of VS_(4) with other carbon nanostructures.展开更多
The uneven distribution and unrich sources of lithium lead to the high cost of lithium-ion batteries(LIBs),which greatly hinders the further widespread use of LIBs[1].Therefore,it is imperative tofind alternative energ...The uneven distribution and unrich sources of lithium lead to the high cost of lithium-ion batteries(LIBs),which greatly hinders the further widespread use of LIBs[1].Therefore,it is imperative tofind alternative energy storage systems to replace LIBs.Potassiumion batteries(PIBs)have been demonstrated to display high operating voltages and high energy/power densities due to the low standard redox potential of K^(+)/K and the fast K+diffusion kinetics in the electrolyte caused by the weak Lewis acidity of K^(+)[2–4].Thus,developing high-performance PIBs is very important and highly desirable[5–7].展开更多
Owing to the shortcomings of traditional electrode materials in alkalimetal-ion batteries(AIBs),such as limited reversible specific capacity,low power density,and poor cycling performance,it is particularly important ...Owing to the shortcomings of traditional electrode materials in alkalimetal-ion batteries(AIBs),such as limited reversible specific capacity,low power density,and poor cycling performance,it is particularly important to develop new electrode materials.Covalent organic frameworks(COFs)are crystalline porous polymers that incorporate organic building blocks into their periodic structures through dynamic covalent bonds.COFs are superior to organic materials because of their high designability,regular channels,and stable topology.Since the first report of D_(TP)-A_(NDI)-COF as a cathode material for lithium-ion batteries in 2015,research on COF electrode materials has made continuous progress and breakthroughs.This review briefly introduces the characteristics and current challenges associated with COF electrode materials.Furthermore,we summarize the basic reaction types and active sites according to the categories of covalent bonds,including B–O,C=N,C–N,and C=C.Finally,we emphasize the perspectives on basic structure and morphology design,dimension and size design,and conductivity improvement of COFs based on the latest progress in AIBs.We believe that this review provides important guidelines for the development of high-efficiency COF electrode materials and devices for AIBs.展开更多
Covalent organic frameworks(COFs), as highly tunable porous crystalline materials, have promising applications in potassium-ion batteries(PIBs) due to their abundant charge carrier transport channels and excellent str...Covalent organic frameworks(COFs), as highly tunable porous crystalline materials, have promising applications in potassium-ion batteries(PIBs) due to their abundant charge carrier transport channels and excellent structural stability. However, the excessive stacking of interlayer electron clouds makes it difficult to expose internal active sites. Strategies to design functional COFs with controllable morphology and copious active sites are promising but still challenging. Herein, by utilizing the condensation between1,3,5-triformylbenzene(TFB) and p-phenylenediamine(PPD) and using amino-modified SiO_(2) nanospheres as templates, we synthesize core-shell NH_(2)-SiO_(2)@TP-COF. Through NaOH etching of NH_(2)-SiO_(2)@TP-COF, we obtain imine-based TP-COF hollow nanospheres, which shows excellent potassium storage performance when applied to the anode for PIBs. Ex-situ analysis and density functional theory calculations reveal that C=N groups and benzenes are active sites for K^(+) storage.展开更多
Metal sulfides have been widely investigated as promising electrode materials for potassium-ion batteries(PIBs)due to their high theoretical capacities.However,the practical application of metal sulfides in PIBs is st...Metal sulfides have been widely investigated as promising electrode materials for potassium-ion batteries(PIBs)due to their high theoretical capacities.However,the practical application of metal sulfides in PIBs is still hindered by their intrinsic shortcomings of low conductivity and severe volume changes during the potassiation/depotassiation process.Herein,a simple template-based two-step annealing strategy is proposed to impregnate CoS_(2) nanoparticles in the well-structured carbon nanocubes(denoted CoS_(2)/CNCs)as an advanced anode material for PIBs.The ex-situ XRD measurements reveal the K+storage mechanism in CoS_(2)/CNCs.Benefiting from the unique structures,including abundant active interfacial sites,high electronic conductivity,and significantly alleviated volume variation,CoS_(2)/CNCs present a high specific capacity(537.3 mAh g^(−1) at 0.1 A g^(−1)),good cycling stability(322.4 mAh g^(−1) at 0.5 A g^(−1) after 300 cycles),and excellent rate capability(153.1 mAh g^(−1) at 5 A g^(−1)).Moreover,the obtained nanocomposite shows superior potassium storage properties in K-ion full cells when it is coupled with a KVPO4F cathode.展开更多
基金supported by the National Natural Science Foundation of China(22075147 and 22179063)。
文摘Although metal oxide compounds are considered as desirable anode materials for potassium-ion batteries(PIBs)due to their high theoretical capacity,the large volume variation remains a key issue in realizing metal oxide anodes with long cycle life and excellent rate property.In this study,polypyrroleencapsulated Sb_(2)WO_(6)(denoted Sb_(2)WO_(6)@PPy)microflowers are synthesized by a one-step hydrothermal method followed by in-situ polymerization and coating by pyrrole.Leveraging the nanosheet-stacked Sb_(2)WO_(6)microflower structure,the improved electronic conductivity,and the architectural protection offered by the PPy coating,Sb_(2)WO_(6)@PPy exhibits boosted potassium storage properties,thereby demonstrating an outstanding rate property of 110.3 m A h g^(-1)at 5 A g^(-1)and delivering a long-period cycling stability with a reversible capacity of 197.2 m A h g^(-1)after 500 cycles at 1 A g^(-1).In addition,the conversion and alloying processes of Sb_(2)WO_(6)@PPy in PIBs with the generation of intermediates,K_(2)WO_(4)and K_(3)Sb,is determined by X-ray photoelectron spectroscopy,transmission electron microscopy,and exsitu X-ray diffraction during potassiation/depotassiation.Density functional theory calculations demonstrate that the robust coupling between PPy and Sb_(2)WO_(6)endues it with a much stronger total density of states and a built-in electric field,thereby increasing the electronic conductivity,and thus effectively reduces the K^(+)diffusion barrier.
基金supported by the National Natural Science Foundation of China(22075147 and 22179063)
文摘Although chalcogenide anodes possess higher potassium storage capacity than intercalated-based graphite,their drastic volume change and the irreversible electrochemical reactions still hinder the effective electron/ion transfer during the potassiation/depotassiation process.To solve the above problems,this article proposes the synthesis of a lamellar nanostructure where graphene nanosheets are embedded with SnSb_(2)Se_(4)nanoparticles(SnSb_(2)Se_(4)/GNS).In the product,fine monodisperse SnSb_(2)Se_(4)nanoparticles are coupled with graphene nanosheets to form a porous network framework,which can effectively mitigate the drastic volume changes during electrode reactions and guarantee efficient potassium-ion storage through the synergistic interactions among multiple elements.Various electrochemical analyses prove that SnSb_(2)Se_(4)inherits the advantages of the binary Sb2Se3 and SnSe while avoiding their disadvantages,confirming the synergistic effect of the ternary–chalcogenide system.When tested for potassium storage,the obtained composite delivers a high specific capacity of 368.5 mAh g^(-1)at 100 mA g^(-1)and a stable cycle performance of 265.8 mAh g^(-1)at 500 mA g^(-1)over 500 cycles.Additionally,the potassium iron hexacyanoferrate cathode and the SnSb_(2)Se_(4)/GNS anode are paired to fabricate the potassium-ion full cell,which shows excellent cyclic stability.In conclusion,this strategy employs atomic doping and interface interaction,which provides new insights for the design of high-rate electrode materials.
基金supported by the National Natural Science Foundation of China(22179063)。
文摘VS_(4) has a unique layered atomic chain structure and has the potential to become a high-performance cathode material of magnesium-ion batteries with a high capacity and long cycle life.However,low conductivity and sluggish Mg^(2+)diffusivity during cycling limit its practical application in large-scale energy storage.Herein,a cooperative assembly-directed strategy is adopted to synthesize VS_(4) nanorods grown in situ on carbon nanotubes(CNTs/VS_(4)).VS_(4) nanorods are tightly anchored to CNTs through V-O-C interface covalent bonds,and CNTs can enhance the electronic conductivity of the nanocomposite.In addition,the ion insertion reaction using Mg^(2+)and Mg Cl^(+)as carriers reduces the polar barrier for divalent Mg^(2+)ion transport.This rationally designed architecture promotes ion diffusion and electron transfer,thus facilitating reaction kinetics.The cooperative assembly-oriented strategy can endow CNTs/VS_(4) with excellent magnesium storage properties,including a high reversible capacity of 223.2 m Ah g^(-1)at a current density of 50 m A g^(-1),a remarkable discharge capacity of 91.8 m Ah g^(-1)even at 2,000 m A g^(-1),and an impressive capacity retention of 85.2% after 1,000 cycles at 500 m A g^(-1).Moreover,this strategy can serve as a general synthetic method for the complexation of VS_(4) with other carbon nanostructures.
基金supported by the National Natural Science Foundation of China(22179063 and 22479078)Qichun Zhang thanks the funding support from the City University of Hong Kong(9380117).
文摘The uneven distribution and unrich sources of lithium lead to the high cost of lithium-ion batteries(LIBs),which greatly hinders the further widespread use of LIBs[1].Therefore,it is imperative tofind alternative energy storage systems to replace LIBs.Potassiumion batteries(PIBs)have been demonstrated to display high operating voltages and high energy/power densities due to the low standard redox potential of K^(+)/K and the fast K+diffusion kinetics in the electrolyte caused by the weak Lewis acidity of K^(+)[2–4].Thus,developing high-performance PIBs is very important and highly desirable[5–7].
基金This work was supported by the National Natural Science Foundation of China(grant no.22179063)Q.Z.gratefully acknowledges the funding support from the City University of Hong Kong(grant nos.9380117,7005620,and 7020040)and Hong Kong Institute for Advanced Study,City University of Hong Kong,Hong Kong,China.
文摘Owing to the shortcomings of traditional electrode materials in alkalimetal-ion batteries(AIBs),such as limited reversible specific capacity,low power density,and poor cycling performance,it is particularly important to develop new electrode materials.Covalent organic frameworks(COFs)are crystalline porous polymers that incorporate organic building blocks into their periodic structures through dynamic covalent bonds.COFs are superior to organic materials because of their high designability,regular channels,and stable topology.Since the first report of D_(TP)-A_(NDI)-COF as a cathode material for lithium-ion batteries in 2015,research on COF electrode materials has made continuous progress and breakthroughs.This review briefly introduces the characteristics and current challenges associated with COF electrode materials.Furthermore,we summarize the basic reaction types and active sites according to the categories of covalent bonds,including B–O,C=N,C–N,and C=C.Finally,we emphasize the perspectives on basic structure and morphology design,dimension and size design,and conductivity improvement of COFs based on the latest progress in AIBs.We believe that this review provides important guidelines for the development of high-efficiency COF electrode materials and devices for AIBs.
基金supported by the National Natural Science Foundation of China (No. 22179063)。
文摘Covalent organic frameworks(COFs), as highly tunable porous crystalline materials, have promising applications in potassium-ion batteries(PIBs) due to their abundant charge carrier transport channels and excellent structural stability. However, the excessive stacking of interlayer electron clouds makes it difficult to expose internal active sites. Strategies to design functional COFs with controllable morphology and copious active sites are promising but still challenging. Herein, by utilizing the condensation between1,3,5-triformylbenzene(TFB) and p-phenylenediamine(PPD) and using amino-modified SiO_(2) nanospheres as templates, we synthesize core-shell NH_(2)-SiO_(2)@TP-COF. Through NaOH etching of NH_(2)-SiO_(2)@TP-COF, we obtain imine-based TP-COF hollow nanospheres, which shows excellent potassium storage performance when applied to the anode for PIBs. Ex-situ analysis and density functional theory calculations reveal that C=N groups and benzenes are active sites for K^(+) storage.
基金This work was supported by the Natural Science Foundation of Jiangsu Province of China(BK20180086).
文摘Metal sulfides have been widely investigated as promising electrode materials for potassium-ion batteries(PIBs)due to their high theoretical capacities.However,the practical application of metal sulfides in PIBs is still hindered by their intrinsic shortcomings of low conductivity and severe volume changes during the potassiation/depotassiation process.Herein,a simple template-based two-step annealing strategy is proposed to impregnate CoS_(2) nanoparticles in the well-structured carbon nanocubes(denoted CoS_(2)/CNCs)as an advanced anode material for PIBs.The ex-situ XRD measurements reveal the K+storage mechanism in CoS_(2)/CNCs.Benefiting from the unique structures,including abundant active interfacial sites,high electronic conductivity,and significantly alleviated volume variation,CoS_(2)/CNCs present a high specific capacity(537.3 mAh g^(−1) at 0.1 A g^(−1)),good cycling stability(322.4 mAh g^(−1) at 0.5 A g^(−1) after 300 cycles),and excellent rate capability(153.1 mAh g^(−1) at 5 A g^(−1)).Moreover,the obtained nanocomposite shows superior potassium storage properties in K-ion full cells when it is coupled with a KVPO4F cathode.
