Hierarchical porous TiOnanopills were synthesized using a titanium metal-organic framework MIL-125（Ti） as precursor. The as-synthesized TiOnanopills owned a large specific surface area of 102 m/g and unique porous s...Hierarchical porous TiOnanopills were synthesized using a titanium metal-organic framework MIL-125（Ti） as precursor. The as-synthesized TiOnanopills owned a large specific surface area of 102 m/g and unique porous structure. Furthermore, the obtained TiOnanopills were applied as anode materials for Na-ion batteries for the first time. The as-synthesized TiOnanopills achieved a high discharge capacity of 196.4 m Ah/g at a current density of 0.1 A/g. A discharge capacity of 115.9 m Ah/g was obtained at a high current density of 0.5 A/g and the capacity retention was remained as high as 90% even after 3000 cycles. The excellent electrochemical performance can be attributed to its unique hierarchical porous feature.展开更多
Currently,the investigation of two-dimensional(2D)crystalline materials,notably transition metal tungsten-based sulfides,is scarcely reported in the wide-temperature field.Thus,tungsten sulphide encapsulated in a sulp...Currently,the investigation of two-dimensional(2D)crystalline materials,notably transition metal tungsten-based sulfides,is scarcely reported in the wide-temperature field.Thus,tungsten sulphide encapsulated in a sulphurized polyacrylonitrile composite(WS_(2)-SPAN)was prepared using an electrospinning technology combined with a sulphuration process.By virtue of the abundant S vacancies and in situ N doping,the WS_(2)-SPAN composite shows an impressively ultralong lifespan and stable circulation capacity over a wide temperature range(−15-50℃).For sodium storage,the WS_(2)-SPAN-2 composite delivers optimized high-rate performance and ultrastable cycling properties(464 mA h g^(-1)/450 cycles at 0.5 A g^(-1);354 mA h g^(-1)/1400 cycles at 2 A g^(-1),190 mA h g^(-1)/12000 cycles at 5 A g^(-1);129 mA h g^(-1)/18000 cycles at 10 A g^(-1),surpassing previously reported WS_(2)-based anodes for SIBs).This is paired with an Na_(3)V_(2)(PO_(4))_(3)cathode,which exhibits excellent storage capacity(241 mA h g^(-1)/200 cycles at 0.5 A g^(-1)).Potassium storage also demonstrates admirable performance(362 mA h g^(-1)/100 cycles at 0.1 A g^(-1);278 mA h g^(-1)/3000 cycles at 1 A g^(-1)).In addition,a detailed illustration of the electrochemical storage mechanism of WS_(2)-SPAN composites is presented through theoretical calculations and electrochemical dynamics.Thus,the present investigation provides new insights into the preparation of novel WS_(2)-based anodes for sodium/potassium-ion batteries with ultralong lifespans and wide-temperature workability.展开更多
Sodium/potassium ion batteries(SIBs/PIBs)are attractive energy storage devices that offer greater sustainability and economic efficiency compared to their lithium-ion battery(LIB)counterparts.However,conventional elec...Sodium/potassium ion batteries(SIBs/PIBs)are attractive energy storage devices that offer greater sustainability and economic efficiency compared to their lithium-ion battery(LIB)counterparts.However,conventional electrode materials with satisfactory cycling stability and rate capacity are still lacking,due to intrinsic low electronic conductivity,sluggish intrinsic ion/electron kinetics and unsatisfactory structural stability.Herein,a well-designed two-step electrospinning/annealing strategy has been employed to fabricate defect-rich WS_(x)Se_(2-x)nanocrystals within selenized polyacrylonitrile fibers(designated as WSSe-Se@PAN).By tuning the Se-doping into the PAN fibers and forming defect-rich WS_(x)Se_(2-x)nanocrystals,the synergistic coupling of S-vacancy regulation can enhance the active sites,expand the interlayer spacing,and accelerate Na^(+)/K^(+)diffusion kinetics,simultaneously.The WSSe-Se@PAN electrode,serving as the anode,delivers a superior sodium storage performance(467 mA h g^(-1)at 2.0 A g^(-1)after 700 cycles),and shows a reversible discharge capacity of 299 mA h g^(-1)at 0.5 A g^(-1)after 60 cycles with 99.8%capacity retention for the sodium ion full batteries.Encouragingly,it displays excellent feasibility in a wide working temperature range between-15 and 50℃ for SIBs.Furthermore,it exhibits high-rate capability and robust cycling life(139 mA h g^(-1)at 1.0 A g^(-1)after 1000 cycles)for PIBs.This work demonstrates that defect engineering of metal chalcogenides by anion doping is a feasible strategy to achieve high-performance anode materials for alkali metal ion batteries.展开更多
Metal selenides are considered potential anode materials for potassium-ion batteries(PIBs)because of their decent theoretical capacity and abundant energy reserves.Nevertheless,selenides display relatively huge volume...Metal selenides are considered potential anode materials for potassium-ion batteries(PIBs)because of their decent theoretical capacity and abundant energy reserves.Nevertheless,selenides display relatively huge volumetric dilatation and slow kinetic reactions,resulting in unsatisfactory rate and cycling performances.Herein,a hybrid material,VSe_(2)/selenized polyacrylonitrile(SePAN),is rationally designed as an anode for PIBs via electrospinning followed by selenidation treatment.SePAN is a dual functional matrix that can efficiently cushion the volumetric variation and provide significant capacity improvement for its chemical bonding effect.Density functional theory(DFT)calculation results demonstrate that the formation of a Se–C bond in SePAN skeletons is beneficial for promoting the charge transfer and the binding interaction between VSe_(2) and the SePAN substrate,favoring an improved storage capacity of selenide species.Moreover,VSe_(2) anchored on the SePAN substrate plays a crucial role in accelerating the reaction kinetics.As expected,the structural virtue endows VSe_(2)/SePAN with high reversibility during potassiation/depotassiation,resulting in an excellent rate capacity(188 mA h g^(−1) at a current density of 5.0 A g^(−1))and a superior cyclability for K+(481 mA h g^(−1) at 0.1 A g^(−1) after 50 cycles)storage at room temperature.Furthermore,the cells still deliver promising electrochemical performance at 0℃,which supplies a new perspective of the electrode in maximizing the desirable K+storage and wide temperature tolerance.展开更多
Developing electrodes with long lifespan and wide-temperature adaptability is crucial important to achieve high-performance sodium/potassium-ion batteries(SIBs/PIBs).Herein,the SnSe2-SePAN composite was fabricated for...Developing electrodes with long lifespan and wide-temperature adaptability is crucial important to achieve high-performance sodium/potassium-ion batteries(SIBs/PIBs).Herein,the SnSe2-SePAN composite was fabricated for extraordinarily stable and wide-temperature range SIBs/PIBs through a coupling strategy between controllable electrospinning and selenylation,in which SnSe2 nanoparticles were uniformly encapsulated in the SePAN matrix.The unique structure of SnSe2-SePAN not only relieves drastic volume variation but also guarantees the structural integrity of the composite,endowing SnSe2-SePAN with excellent sodium/potassium storage properties.Consequently,SnSe2-SePAN displays a high sodium storage capacity and excellent feasibility in a wide working temperature range(-15 to 60℃:300 mAh g^(-1)/700 cycles/-15℃;352 mAh g^(-1)/100 cycles/60℃at 0.5 A g^(-1)).At room temperature,it delivers a record-ultralong cycling life of 192 mAh g^(-1)that exceeds 66000 cycles even at 15 A g^(-1).It exhibits extremely superb electrochemical performance in PIBs(157 mAh g^(-1)exceeding 15000 cycles at 5 A g^(-1)).The ex situ XRD and TEM results attest the conversion-alloy mechanism of SnSe2-SePAN.Also,computational calculations verify that SePAN takes an important role in intensifying the electrochemical performance of SnSe2-SePAN electrode.Therefore,this study breaks new ground on solving the polyselenide dissolution issue and improving the wide temperature workable performance of sodium/potassium storage.展开更多
基金supported by JSPS KAKENHI Grant Number15K00597Takahashi Industrial and Economic Research Foundation Japan Grant Number 06-003-154
文摘Hierarchical porous TiOnanopills were synthesized using a titanium metal-organic framework MIL-125（Ti） as precursor. The as-synthesized TiOnanopills owned a large specific surface area of 102 m/g and unique porous structure. Furthermore, the obtained TiOnanopills were applied as anode materials for Na-ion batteries for the first time. The as-synthesized TiOnanopills achieved a high discharge capacity of 196.4 m Ah/g at a current density of 0.1 A/g. A discharge capacity of 115.9 m Ah/g was obtained at a high current density of 0.5 A/g and the capacity retention was remained as high as 90% even after 3000 cycles. The excellent electrochemical performance can be attributed to its unique hierarchical porous feature.
基金financially supported by the National Key Research and Development Program of China(2019YFC1904500)the National Natural Science Foundation of China(NSFC 51502036 and 21875037)+2 种基金the Department of Ecology and Environment of Fujian Province(2021R024)the Young Top Talent of Fujian Young Eagle Program of Fujian Province,the Educational Commission of Fujian Province(2022G02022)the Natural Science Foundation of Distinguished Young Scholars for Fujian Province(2019J06015).
文摘Currently,the investigation of two-dimensional(2D)crystalline materials,notably transition metal tungsten-based sulfides,is scarcely reported in the wide-temperature field.Thus,tungsten sulphide encapsulated in a sulphurized polyacrylonitrile composite(WS_(2)-SPAN)was prepared using an electrospinning technology combined with a sulphuration process.By virtue of the abundant S vacancies and in situ N doping,the WS_(2)-SPAN composite shows an impressively ultralong lifespan and stable circulation capacity over a wide temperature range(−15-50℃).For sodium storage,the WS_(2)-SPAN-2 composite delivers optimized high-rate performance and ultrastable cycling properties(464 mA h g^(-1)/450 cycles at 0.5 A g^(-1);354 mA h g^(-1)/1400 cycles at 2 A g^(-1),190 mA h g^(-1)/12000 cycles at 5 A g^(-1);129 mA h g^(-1)/18000 cycles at 10 A g^(-1),surpassing previously reported WS_(2)-based anodes for SIBs).This is paired with an Na_(3)V_(2)(PO_(4))_(3)cathode,which exhibits excellent storage capacity(241 mA h g^(-1)/200 cycles at 0.5 A g^(-1)).Potassium storage also demonstrates admirable performance(362 mA h g^(-1)/100 cycles at 0.1 A g^(-1);278 mA h g^(-1)/3000 cycles at 1 A g^(-1)).In addition,a detailed illustration of the electrochemical storage mechanism of WS_(2)-SPAN composites is presented through theoretical calculations and electrochemical dynamics.Thus,the present investigation provides new insights into the preparation of novel WS_(2)-based anodes for sodium/potassium-ion batteries with ultralong lifespans and wide-temperature workability.
基金supported by the National Key Research and Development Program of China(2023YFC3906300 and 2019YFC1904500)National Natural Science Foundation of China(NSFC 51502036 and 21875037)+3 种基金the Young Top Talent of Fujian Young Eagle Program of Fujian Province,Educational Commission of Fujian Province(2022G02022)Key Project for Technology Innovation and Industrialization of Fujian Province(2023G002)Natural Science Foundation of Fuzhou City(2022-Y-004)Natural Science Foundation of Fujian Province(2023J02013 and 2023YZ038001).
文摘Sodium/potassium ion batteries(SIBs/PIBs)are attractive energy storage devices that offer greater sustainability and economic efficiency compared to their lithium-ion battery(LIB)counterparts.However,conventional electrode materials with satisfactory cycling stability and rate capacity are still lacking,due to intrinsic low electronic conductivity,sluggish intrinsic ion/electron kinetics and unsatisfactory structural stability.Herein,a well-designed two-step electrospinning/annealing strategy has been employed to fabricate defect-rich WS_(x)Se_(2-x)nanocrystals within selenized polyacrylonitrile fibers(designated as WSSe-Se@PAN).By tuning the Se-doping into the PAN fibers and forming defect-rich WS_(x)Se_(2-x)nanocrystals,the synergistic coupling of S-vacancy regulation can enhance the active sites,expand the interlayer spacing,and accelerate Na^(+)/K^(+)diffusion kinetics,simultaneously.The WSSe-Se@PAN electrode,serving as the anode,delivers a superior sodium storage performance(467 mA h g^(-1)at 2.0 A g^(-1)after 700 cycles),and shows a reversible discharge capacity of 299 mA h g^(-1)at 0.5 A g^(-1)after 60 cycles with 99.8%capacity retention for the sodium ion full batteries.Encouragingly,it displays excellent feasibility in a wide working temperature range between-15 and 50℃ for SIBs.Furthermore,it exhibits high-rate capability and robust cycling life(139 mA h g^(-1)at 1.0 A g^(-1)after 1000 cycles)for PIBs.This work demonstrates that defect engineering of metal chalcogenides by anion doping is a feasible strategy to achieve high-performance anode materials for alkali metal ion batteries.
基金supported by the National Key R&D Program of China(2019YFC1904500)the National Natural Science Foundation of China(NSFC 21875037 and 51502036)+2 种基金the Young Top Talent of Fujian Young Eagle Program,Educational Commission of Fujian Province(2022G02022)the Science and Technology Commission of Fujian Province(2022J05195 and 2023J02013)the Department and Education of Fujian Province(JAT210296).
文摘Metal selenides are considered potential anode materials for potassium-ion batteries(PIBs)because of their decent theoretical capacity and abundant energy reserves.Nevertheless,selenides display relatively huge volumetric dilatation and slow kinetic reactions,resulting in unsatisfactory rate and cycling performances.Herein,a hybrid material,VSe_(2)/selenized polyacrylonitrile(SePAN),is rationally designed as an anode for PIBs via electrospinning followed by selenidation treatment.SePAN is a dual functional matrix that can efficiently cushion the volumetric variation and provide significant capacity improvement for its chemical bonding effect.Density functional theory(DFT)calculation results demonstrate that the formation of a Se–C bond in SePAN skeletons is beneficial for promoting the charge transfer and the binding interaction between VSe_(2) and the SePAN substrate,favoring an improved storage capacity of selenide species.Moreover,VSe_(2) anchored on the SePAN substrate plays a crucial role in accelerating the reaction kinetics.As expected,the structural virtue endows VSe_(2)/SePAN with high reversibility during potassiation/depotassiation,resulting in an excellent rate capacity(188 mA h g^(−1) at a current density of 5.0 A g^(−1))and a superior cyclability for K+(481 mA h g^(−1) at 0.1 A g^(−1) after 50 cycles)storage at room temperature.Furthermore,the cells still deliver promising electrochemical performance at 0℃,which supplies a new perspective of the electrode in maximizing the desirable K+storage and wide temperature tolerance.
基金supported by the National Key R&D Program of China(2019YFC1904500)National Natural Science Foundation of China(NSFC 21875037 and 51502036)+3 种基金Department of Ecology and Environment of Fujian Province(2021R024)the Young Top Talent of Fujian Young Eagle Program,Educational Commission of Fujian Province(2022G02022)Natural Science Foundation of Fujian Province(2023J02013 and 2019J06015)Natural Science Foundation of Fuzhou City(2022-Y-004).
文摘Developing electrodes with long lifespan and wide-temperature adaptability is crucial important to achieve high-performance sodium/potassium-ion batteries(SIBs/PIBs).Herein,the SnSe2-SePAN composite was fabricated for extraordinarily stable and wide-temperature range SIBs/PIBs through a coupling strategy between controllable electrospinning and selenylation,in which SnSe2 nanoparticles were uniformly encapsulated in the SePAN matrix.The unique structure of SnSe2-SePAN not only relieves drastic volume variation but also guarantees the structural integrity of the composite,endowing SnSe2-SePAN with excellent sodium/potassium storage properties.Consequently,SnSe2-SePAN displays a high sodium storage capacity and excellent feasibility in a wide working temperature range(-15 to 60℃:300 mAh g^(-1)/700 cycles/-15℃;352 mAh g^(-1)/100 cycles/60℃at 0.5 A g^(-1)).At room temperature,it delivers a record-ultralong cycling life of 192 mAh g^(-1)that exceeds 66000 cycles even at 15 A g^(-1).It exhibits extremely superb electrochemical performance in PIBs(157 mAh g^(-1)exceeding 15000 cycles at 5 A g^(-1)).The ex situ XRD and TEM results attest the conversion-alloy mechanism of SnSe2-SePAN.Also,computational calculations verify that SePAN takes an important role in intensifying the electrochemical performance of SnSe2-SePAN electrode.Therefore,this study breaks new ground on solving the polyselenide dissolution issue and improving the wide temperature workable performance of sodium/potassium storage.
