KFeSO_(4)F(KFSF)is considered a potential cathode due to the large capacity and low cost.However,the inferior electronic conductivity leads to poor electrochemical performance.Defect engineering can facilitate the ele...KFeSO_(4)F(KFSF)is considered a potential cathode due to the large capacity and low cost.However,the inferior electronic conductivity leads to poor electrochemical performance.Defect engineering can facilitate the electron/ion transfer by tuning electronic structure,thus providing favorable electrochemical performance.Herein,through the regulation of surface defect engineering in reduced graphene oxide(rGO),the Fe–C bonds were formed between KFSF and rGO.The Fe–C bonds formed work in regulating the Fe-3d orbital as well as promoting the migration ability of K ions and increasing the electronic conductivity of KFSF.Thus,the KFSF@rGO delivers a high capacity of 119.6 mAh g^(-1).When matched with a graphite@pitch-derived S-doped carbon anode,the full cell delivers an energy density of 250.5 Wh kg^(-1) and a capacity retention of 81.5%after 400 cycles.This work offers a simple and valid method to develop high-performance cathodes by tuning defect sites.展开更多
Electrochemical energy storage and conversion techniques that exhibit the merits such as high energy density,rapid response kinetics,economical maintenance requirements and expedient installation procedures will hold ...Electrochemical energy storage and conversion techniques that exhibit the merits such as high energy density,rapid response kinetics,economical maintenance requirements and expedient installation procedures will hold a pivotal role in the forthcoming energy storage technologies revolution.In recent years,aqueous zinc-ion batteries(AZIBs)have garnered substantial attention as a compelling candidate for large-scale energy storage systems,primarily attributable to their advantageous featu res encompassing cost-effectiveness,environmental sustainability,and robust safety profiles.Currently,one of the primary factors hindering the further development of AZIBs originates from the challenge of cathode materials.Specifically,the three mainstream types of mainstream cathode materials,in terms of manganese-based compounds,vanadium-based compounds and Prussian blue analogues,surfer from the dissolution of Mn~(2+),in the low discharge voltage,and the low specific capacity,respectively.Several strategies have been developed to compensation the above intrinsic defects for these cathode materials,including the ionic doping,defect engineering,and materials match.Accordingly,this review first provides a systematic summarization of the zinc storage mechanism in AZIBs,following by the inherent merit and demerit of three kind of cathode materials during zinc storage analyzed from their structure characteristic,and then the recent development of critical strategies towards the intrinsic insufficiency of these cathode materials.In this review,the methodologies aimed at enhancing the efficacy of manganese-based and vanadium-based compounds are emphasis emphasized.Additionally,the article outlines the future prospective directions as well as strategic proposal for cathode materials in AZIBs.展开更多
Artificial intelligence(AI), particularly deep learning algorithms, is gaining extensive attention for its excellent performance in image-recognition tasks. They can automatically make a quantitative assessment of com...Artificial intelligence(AI), particularly deep learning algorithms, is gaining extensive attention for its excellent performance in image-recognition tasks. They can automatically make a quantitative assessment of complex medical image characteristics and achieve an increased accuracy for diagnosis with higher efficiency. AI is widely used and getting increasingly popular in the medical imaging of the liver, including radiology, ultrasound, and nuclear medicine. AI can assist physicians to make more accurate and reproductive imaging diagnosis and also reduce the physicians' workload. This article illustrates basic technical knowledge about AI, including traditional machine learning and deep learning algorithms, especially convolutional neural networks, and their clinical application in the medical imaging of liver diseases, such as detecting and evaluating focal liver lesions, facilitating treatment, and predicting liver treatment response. We conclude that machine-assisted medical services will be a promising solution for future liver medical care. Lastly, we discuss the challenges and future directions of clinical application of deep learning techniques.展开更多
Graphite as a promising anode candidate of K-ion batteries(KIBs)has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials.To pr...Graphite as a promising anode candidate of K-ion batteries(KIBs)has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials.To protect the layer structure and further boost performance,tempura-like carbon/carbon nanocomposite of graphite@pitch-derived S-doped carbon(G@PSC)is designed and prepared by a facile and low-temperature modified molten salt method.This robust encapsulation structure makes their respective advantages complementary to each other,showing mutual promotion of electrochemical performances caused by synergy effect.As a result,the G@PSC electrode is applied in KIBs,delivering impressive rate capabilities(465,408,370,332,290,and 227 m A h g^(-1)at 0.05,0.2,0.5,1,2,and 5 A g^(-1))and ultralong cyclic stability(163 m A g^(-1)remaining even after 8000 cycles at 2 A g^(-1)).On basis of ex-situ studies,the sectionalized K-storage mechanism with adsorption(pseudocapacitance caused by S doping)-intercalation(pitch-derived carbon and graphite)pattern is revealed.Moreover,the exact insights into remarkable rate performances are taken by electrochemical kinetics tests and density functional theory calculation.In a word,this study adopts a facile method to synthesize high-performance carbon/carbon nanocomposite and is of practical significance for development of carbonaceous anode in KIBs.展开更多
Dual-ion battery(DIB) composed of graphite cathode and lithium anode is regarded as an advanced secondary battery because of the low cost, high working voltage and environmental friendliness. However,DIB operated at h...Dual-ion battery(DIB) composed of graphite cathode and lithium anode is regarded as an advanced secondary battery because of the low cost, high working voltage and environmental friendliness. However,DIB operated at high potential(usually ≥ 4.5 V versus Li+/Li) is confronted with severe challenges including electrolyte decomposition on cathode interface, and structural deterioration of graphite accompanying with anions de-/intercalation, hinder its cyclic life. To address those drawbacks and preserve the DIB virtues, a feasible and scalable surface modification is achieved for the commercial graphite cathode of mesocarbon microbead. In/ex-situ studies reveal that, such an interfacial engineering facilitates and reconstructs the formation of chemically stable cathode electrolyte interphase with better flexibility alleviating the decomposition of electrolyte, regulating the anions de-/intercalation behavior in graphite with the retainment of structural integrity and without exerting considerable influence on kinetics of anions diffusion. As a result, the modified mesocarbon microbead exhibits a much-extended cycle life with high capacity retention of 82.3% even after 1000 cycles. This study demonstrates that the interface modification of electrode and coating skeleton play important roles on DIB performance improvement, providing the feasible basis for practical application of DIB owing to the green and scalable coating procedures.展开更多
With the increasing popularity of new en ergy electric vehicles,the dema nd for lithium-ion batteries(LIBs)has been growing rapidly,which will produce a large number of spent LIBs.Therefore,recycling of spe nt LIBs ha...With the increasing popularity of new en ergy electric vehicles,the dema nd for lithium-ion batteries(LIBs)has been growing rapidly,which will produce a large number of spent LIBs.Therefore,recycling of spe nt LIBs has become an urge nt task to be solved,otherwise it will inevitably lead to serious environmental pollution.Herein,a unique recycling strategy is proposed to achieve the concurrent reuse of cathode and anode in the spent graphite/LiFePO_(4) batteries.Along with such recycling process,a unique cathode composed of recycled LFP/graphite(RLFPG)with cation/anion-co-storage ability is designed for new-type dual-ion battery(DIB).As a result,the recycle-derived DIB of Li/RLFPG is established with good electrochemical performance,such as an initial discharge capacity of 117.4 mA h g^(-1) at 25 mA g^(-1) and 78% capacity retention after 1000 cycles at 100 mA g^(-1).The working mechanism of Li/RLFPG DIB is also revealed via in situ X-ray diffraction and electrode kinetics studies.This work not only presents a farreaching significance for large-scale recycling of spent LIBs in the future,but also proposed a sustainable and econo mical method to design n ew-type sec on dary batteries as recycling of spe nt LIBs.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
BACKGROUND Localized primary gastric amyloidosis is a rare disorder characterized by the extracellular deposition of insoluble fibrillary protein in the stomach and can mimic various diseases on endoscopic examination...BACKGROUND Localized primary gastric amyloidosis is a rare disorder characterized by the extracellular deposition of insoluble fibrillary protein in the stomach and can mimic various diseases on endoscopic examination,including gastrointestinal stromal tumors,gastric cancer and ulcers.CASE SUMMARIES Here,we report a series of three cases of localized gastric amyloidosis mimicking gastric mucosa-associated lymphoid tissue(MALT)lymphoma on endoscopic examination that were evaluated over the past ten years in our hospital.The different detection times of this rare disease resulted in three completely different outcomes,indicating the strong importance of early detection,diagnosis and treatment.The difficulties encountered in making an accurate diagnosis and differential diagnosis are highlighted,and this report provides clinical experience for the diagnosis of localized primary gastric amyloidosis.CONCLUSION Localized gastric amyloidosis is a rare metabolic disease that resembles MALT lymphoma.Early detection,diagnosis and treatment of localized gastric amyloidosis result in an excellent prognosis.展开更多
With the continuous advancement of industrialization,sodium-ion batteries(SIBs)need to operate in various challenging circumstances,particularly in extremely cold conditions.However,at ultra-low tem-peratures,the redu...With the continuous advancement of industrialization,sodium-ion batteries(SIBs)need to operate in various challenging circumstances,particularly in extremely cold conditions.However,at ultra-low tem-peratures,the reduced ionic conductivity and sluggish Na+migration of commonly carbonate-based elec-trolytes will inevitably lead to a sharp decrease in the capacity of SIBs.Herein,we design a carboxylate ester-based electrolyte with excellent ultra-low temperature performance by straightforward cosolvent strategy.Due to the low viscosity,melting point,and sufficient ionic conductivity of the designed elec-trolyte,the resulting Na||Na_(3)V_(2)(PO_(4))_(2)O_(2)F can achieve the capacity retention of 96%(100 cycles at 0.1 C)at-40℃ and can also operate stably even at-50℃.Besides,galvanostatic intermittent titration tech-nique(GITT),ex-situ X-ray photoelectron spectroscopy(XPS),and high-resolution transmission electron microscopy(TEM)tests are employed to analyze and confirm that the carboxylate ester-based electrolyte promotes robust and uniform cathode/electrolyte interface layer formation and accelerates ion diffusion kinetics,which collectively facilitates the better low-temperature performance.In addition,the assembled hard carbon||NVPOF full cells further prove the practicability of the carboxylate ester-based electrolyte at low-temperature,which delivers high discharge capacity of 108.4 and 73.0 mAh g^(-1) at-25 and-40℃.This work affords a new avenue for designing advanced low-temperature electrolytes for SIBs.展开更多
Hard carbon(HC)is broadly recognized as an exceptionally prospective candidate for the anodes of sodium-ion batteries(SIBs),but their practical implementation faces substantial limitations linked to precursor factors,...Hard carbon(HC)is broadly recognized as an exceptionally prospective candidate for the anodes of sodium-ion batteries(SIBs),but their practical implementation faces substantial limitations linked to precursor factors,such as reduced carbon yield and increased cost.Herein,a cost-effective approach is proposed to prepare a coal-derived HC anode with simple pre-oxidation followed by a post-carbonization process which effectively expands the d_(002)layer spacing,generates closed pores and increases defect sites.Through these modifications,the resulting HC anode attains a delicate equilibrium between plateau capacity and sloping capacity,showcasing a remarkable reversible capacity of 306.3 mAh·g^(-1)at 0.03 A·g^(-1).Furthermore,the produ ced HC exhibits fast reaction kinetics and exceptional rate performance,achieving a capacity of 289 mAh·g^(-1)at 0.1 A·g^(-1),equivalent to~94.5%of that at 0.03 A·g^(-1).When implemented in a full cell configuration,the impressive electrochemical performance is evident,with a notable energy density of 410.6 Wh·kg^(-1)(based on cathode mass).In short,we provide a straightforward yet efficient method for regulating coal-derived HC,which is crucial for the widespread use of SIBs anodes.展开更多
Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep ...Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space explorations.To achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel,a comprehensive design of a multi-functional detector is indispensable.In this study,we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency(91.6%),high photon counting rate(1.61 Gcps),large dynamic range for resolving different photon numbers(1-24),and four-quadrant position sensing function all within one device.Furthermore,we have constructed a communication testbed to validate the advantages offered by such an architecture.Through 8-PPM(pulse position modulation)format communication experiments,we have achieved an impressive maximum data rate of 1.5 Gbps,demonstrating sensitivities surpassing previous benchmarks at respective speeds.By incorporating photon number information into error correction codes,the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps—showcasing a great potential for daylight operation scenarios.Additionally,preliminary beam tracking tests were conducted through open-loop scanning techniques,which revealed clear quantitative dependence indicating sensitivity variations based on beam location.Based on the device characterizations and communication results,we anticipate that this device architecture,along with its corresponding signal processing and coding techniques,will be applicable in future space-to-ground communication tasks.展开更多
Effective design of nanoheterostructure anode with high ion/electron migration kinetics can give electrode with superior electrochemical performance.However,the design and preparation of nanoheterostructure composites...Effective design of nanoheterostructure anode with high ion/electron migration kinetics can give electrode with superior electrochemical performance.However,the design and preparation of nanoheterostructure composites with high-capacity and long cycling life in half and pouch full cells remain a big challenge.Here,a novel micro-pore MnS/Mn_(2)SnS_(4)heterostructure nanowire were in situ encapsulated into the N and S elements co-doped amorphous carbon tubes(abbreviated as(MnS/Mn_(2)SnS_(4))@N,S-ACTs)and showed superior energy storage properties in Na-/Li-ion half cells and pouch full cells.The Na-/Li-storage capabilities improvement are attribute to the strong synergistic effect between MnS/Mn_(2)SnS_(4)heterostructure and N,S-ACTs protective layer,the former induces an local built-in electric field between Mn_(2)Sn S_(4)and MnS during charging/discharging,accelerating interfacial ion/electron diffusion dynamics,the latter effective maintains the morphology and volume evolution during Na~+/Li~+charging/discharging,achieving a long-term cycling stability(e.g.,high discharge capacity of 79.2 mAh/g with the capacity retention of 79.3%can be gained after 2200 cycles at 3 C in(Mn S/Mn_(2)Sn S_(4))@N,S-ACTs//LiFePO_(4)pouch full cells;a high capacity of~34 mAh/g at 10 C can be got with a Coulombic efficiency of 100%after 1000 cycles in pouch(Mn S/Mn_(2)Sn S_(4))@N,S-ACTs//Na_(3)V_(2)(PO_(4))_(2)O_(2)F full cells.展开更多
Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) are the most promising alternatives to lithium-ion batteries, and thus have drawn intensive research attention. Porous carbon materials from different precu...Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) are the most promising alternatives to lithium-ion batteries, and thus have drawn intensive research attention. Porous carbon materials from different precursors have been widely used as anode materials owing to their compatible storage effectiveness of both larger radii sodium and potassium ions. However, the differential bonding behaviors of Na and K ions with porous carbon-based anode are the significant one worth investigating, which could provide a clean picture of alkali ions storage mechanism. Therefore, in this work, we prepare a porous carbon network derived from sawdust(SDC) wastes, to further analyze the differences on sodium and potassium ions storage behaviors in terms of bond-forming process. It is found that, as-prepared SDC anodes could deliver stable sodium and potassium storage capacities, however, there are notable distinctions in terms of electrochemical behaviors and diffusion processes. By virtue of ex-situ XRD and Raman spectroscopy, the phase transition reaction of potassium ions could be well-observed, and the results shows that the multiple intercalated compounds was formed in SDC network during ions insertion, further resulting in slower diffusion kinetics and larger resistance compared to non-bonded process of sodium ions storage. This study provides more insights into the differences between sodium and potassium ions storage, as well as the energy storage mechanism of porous carbon as anodes for secondary batteries.展开更多
Nowadays,lithium-ion batteries(LIBs)play a crucial role in modern society in the aspect of portable electronic devices and large-scale smart grids.However,the current performance of lithium-ion batteries has been unab...Nowadays,lithium-ion batteries(LIBs)play a crucial role in modern society in the aspect of portable electronic devices and large-scale smart grids.However,the current performance of lithium-ion batteries has been unable to meet the growing expectations of society and scientific community.Herein,we have synthetically investigated availability of 2D Ni-TABQ monolayer as anode based on DFT for LIBs applications.Our findings have demonstrated that 2D Ni-TABQ monolayer is a semiconductor with a small band gap of 0.2 eV,which suggest that the electronic property of 2D Ni-TABQ monolayer would take place an evident shift from semiconductor property to metallic property after Li adsorption.Furthermore,we checked the stability of 2D Ni-TABQ monolayer and investigated the viability of exfoliation from bulk multilayer Ni-TABQ to form 2D Ni-TABQ monolayer in the light of exfoliation energy and binding energy.We continuously studied electrochemical properties of 2D Ni-TABQ monolayer with respect of theoretical specific capacity,Li-ion diffusion barriers and open-circuit voltage.During the charging process,2D Ni-TABQ monolayer can achieve a high specific capacity of 722 m Ah/g with an open-circuit voltage range from 1.12 V to 0.22 V.These aforementioned results make the 2D Ni-TABQ monolayer a promising anode for LIBs.展开更多
As the need for energy storage devices escalates,aqueous zincion batteries(ZIBs)have risen as a promising alternative to the widely used Li-ion batteries,offering intrinsic safety,environmental compatibility,and cost ...As the need for energy storage devices escalates,aqueous zincion batteries(ZIBs)have risen as a promising alternative to the widely used Li-ion batteries,offering intrinsic safety,environmental compatibility,and cost advantages,positioning them as attractive energy storage systems for the future[1,2].However,challenges such as dendrite growth on Zn anodes,stemming from uneven electric fields on the surface and active water side reactions,compromise cycling stability and lifespan,posing significant hurdles for the practical application of ZIBs[3,4].To mitigate these issues,strategies like electrolyte optimization,artificial solid electrolyte interphase(SEI)layers,and current collector modifications have been proposed[5,6].Nevertheless,most long-cycle experiments are conducted at low current densities and deposition capacities,with high current density and capacity operations typically lasting less than 1000 h[7].展开更多
Acid hydrogen evolution reaction(HER)is a critical energy conversion process,which is significantly important in hydrogen energy manufacturing and storage[1].Although the performance of noble metal platinum(Pt)-based ...Acid hydrogen evolution reaction(HER)is a critical energy conversion process,which is significantly important in hydrogen energy manufacturing and storage[1].Although the performance of noble metal platinum(Pt)-based catalysts in acidic HER is well known,the challenges are high cost,limited reserves,poor stability,and susceptibility to toxic substances[2].Therefore,it is urgent to design and manufacture acidic HER catalysts with high reactivity,high stability,and low cost.展开更多
One main challenge for phosphate cathodes in sodium-ion batteries(SIBs)is to increase the working voltage and energy density to promote its practicability.Herein,an advanced Na3V2(PO4)2F3@C cathode is prepared success...One main challenge for phosphate cathodes in sodium-ion batteries(SIBs)is to increase the working voltage and energy density to promote its practicability.Herein,an advanced Na3V2(PO4)2F3@C cathode is prepared successfully for sodium-ion full cells.It is revealed that,carbon coating can not only enhance the electronic conductivity and electrode kinetics of Na3V2(PO4)2F3@C and inhibit the growth of particles(i.e.,shorten the Na^+-migration path),but also unexpectedly for the first time adjust the dis-/charging plateaux at different voltage ranges to increase the mean voltage(from 3.59 to 3.71 V)and energy density from 336.0 to 428.5 Wh kg^-1 of phosphate cathode material.As a result,when used as cathode for SIBs,the prepared Na3V2(PO4)2F3@C delivers much improved electrochemical properties in terms of larger specifc capacity(115.9 vs.93.5 mAh g^-1),more outstanding high-rate capability(e.g.,87.3 vs.60.5 mAh g^-1 at 10 C),higher energy density,and better cycling performance,compared to pristine Na3V2(PO4)2F3.Reasons for the enhanced electrochemical properties include ionicity enhancement of lattice induced by carbon coating,improved electrode kinetics and electronic conductivity,and high stability of lattice,which is elucidated clearly through the contrastive characterization and electrochemical studies.Moreover,excellent energy-storage performance in sodium-ion full cells further demonstrate the extremely high possibility of Na3V2(PO4)2F3@C cathode for practical applications.展开更多
In recent years,sodium-ion batteries(SIBs)have been considered as one of the most promising alternatives to lithium-ion batteries(LIBs).Here,a new Na-super-ionic conductor(NASICON)cathode material Na Fe_(2)PO_(4)(SO_(...In recent years,sodium-ion batteries(SIBs)have been considered as one of the most promising alternatives to lithium-ion batteries(LIBs).Here,a new Na-super-ionic conductor(NASICON)cathode material Na Fe_(2)PO_(4)(SO_(4))_(2)is successfully prepared through solid state method for SIBs.While the poor electronic conductivity of iron-based materials results in its poor rate and cycle performance.Then the electrochemical is effectively promoting via Ca^(2+)doping.Na_(0.84)Ca_(0.08)Fe_(2)PO_(4)(SO_(4))_(2)have achieved considerable electrochemical properties.The first discharge specific capacity is 121.6 m A h g^(-1)at 25 m A g^(-1)with the voltage platform(-3.1 V)corresponding to Fe^(2+/3+).After 100 cycles,the capacity retention is 55.1%.The excellent electrochemical performance is caused by some Na^(+)is substituted by Ca^(2+)and leading to the fast sodium kinetics,which is well proved by the powder X-ray diffraction pattern and well corresponding to the galvanostatic intermittent titration technique and cyclic voltammetry testing result(the diffusivity values are around at 10^(-12)cm^(2)s^(-1)).展开更多
Due to the serious imbalance between demand and supply of lithium,lithium extraction from brine has become a research hotspot.With the demand for power lithium-ion batteries(LIBs)increased rapidly,a large number of sp...Due to the serious imbalance between demand and supply of lithium,lithium extraction from brine has become a research hotspot.With the demand for power lithium-ion batteries(LIBs)increased rapidly,a large number of spent LiFePO_(4)power batteries have been scrapped and entered the recycling stage.Herein,a novel and efficient strategy is proposed to extract lithium from brine by directly reusing spent LiFePO_(4)powder without any treatment.Various electrochemical test results show that spent LiFePO_(4)electrode has appropriate lithium capacity(14.62 mg_(Li)/g_(LiFePO_(4))),excellent separation performance(α_(Li-Na)=210.5)and low energy consumption(0.768 Wh/g_(Li))in electrochemical lithium extraction from simulated brine.This work not only provides a novel idea for lithium extraction from brine,but also develops an effective strategy for recycling spent LIBs.The concept of from waste to wealth is of great significance to the development of recycling the spent batteries.展开更多
As a cathode for sodium-ion batteries(SIBs),Na3V2(PO4)2F3(NVPF)with 3D open framework is a promising candidate due to its high working voltage and large theoretical capacity.However,the severe capacity degradation and...As a cathode for sodium-ion batteries(SIBs),Na3V2(PO4)2F3(NVPF)with 3D open framework is a promising candidate due to its high working voltage and large theoretical capacity.However,the severe capacity degradation and poor rate capability hinder its practical applications.The present study demonstrated the optimization of Na-storage performance of NVPF via delicate lattice modulation.Aliovalent substitution of V^(3^(+))at Na^(+)in NVPF induces the generation of electronic defects and expansion of Na^(+)-migration channels,resulting in the enhancement in electronic conductivity and acceleration of Na^(+)-migration kinetics.It is disclosed that the formed stronger Na O bonds with high ionicity than V O bonds lead to the significant increase in structural stability and ionicity in the Na^(+)-substituted NVPF(NVPF-Nax).The aforementioned effects of Na^(+)substitution achieve the unprecedented electrochemical performance in the optimized Na_(3.14)V1.93Na0.07(PO_(4))_(2)F_(3)(NVPF-Na_(0.07)).As a result,NVPF-Na0.07 delivers a high-rate capability(77.5 mAh g^(−1)at 20 C)and ultralong cycle life(only 0.027%capacity decay per cycle over 1000 cycles at 10 C).Sodium-ion full cells are designed using NVPF-Na0.07 as cathode and Se@reduced graphene oxide as anode.The full cells exhibit excellent wide-temperature electrochemical performance from−25 to 25C with an outstanding rate capability(96.3 mAh g^(−1)at 20 C).Furthermore,it delivered an excellent cycling performance over 300 cycles with a capacity retention exceeding 90%at 0.5 C under different temperatures.This study demonstrates a feasible strategy for the development of advanced cathode materials with excellent electrochemical properties to achieve high-efficiency energy storage.展开更多
基金support from the National Key R&D Program of China(Grant No.2023YFE0202000)National Natural Science Foundation of China(Grant No.52102213)Science Technology Program of Jilin Province(Grant No.20230101128JC).
文摘KFeSO_(4)F(KFSF)is considered a potential cathode due to the large capacity and low cost.However,the inferior electronic conductivity leads to poor electrochemical performance.Defect engineering can facilitate the electron/ion transfer by tuning electronic structure,thus providing favorable electrochemical performance.Herein,through the regulation of surface defect engineering in reduced graphene oxide(rGO),the Fe–C bonds were formed between KFSF and rGO.The Fe–C bonds formed work in regulating the Fe-3d orbital as well as promoting the migration ability of K ions and increasing the electronic conductivity of KFSF.Thus,the KFSF@rGO delivers a high capacity of 119.6 mAh g^(-1).When matched with a graphite@pitch-derived S-doped carbon anode,the full cell delivers an energy density of 250.5 Wh kg^(-1) and a capacity retention of 81.5%after 400 cycles.This work offers a simple and valid method to develop high-performance cathodes by tuning defect sites.
基金supported by the Science and Technology Development Planning of Jilin Province (20240101153JC)the Department of Education of Jilin Province (JJKH20240905KJ)the National Natural Science Foundation of China (21972133)。
文摘Electrochemical energy storage and conversion techniques that exhibit the merits such as high energy density,rapid response kinetics,economical maintenance requirements and expedient installation procedures will hold a pivotal role in the forthcoming energy storage technologies revolution.In recent years,aqueous zinc-ion batteries(AZIBs)have garnered substantial attention as a compelling candidate for large-scale energy storage systems,primarily attributable to their advantageous featu res encompassing cost-effectiveness,environmental sustainability,and robust safety profiles.Currently,one of the primary factors hindering the further development of AZIBs originates from the challenge of cathode materials.Specifically,the three mainstream types of mainstream cathode materials,in terms of manganese-based compounds,vanadium-based compounds and Prussian blue analogues,surfer from the dissolution of Mn~(2+),in the low discharge voltage,and the low specific capacity,respectively.Several strategies have been developed to compensation the above intrinsic defects for these cathode materials,including the ionic doping,defect engineering,and materials match.Accordingly,this review first provides a systematic summarization of the zinc storage mechanism in AZIBs,following by the inherent merit and demerit of three kind of cathode materials during zinc storage analyzed from their structure characteristic,and then the recent development of critical strategies towards the intrinsic insufficiency of these cathode materials.In this review,the methodologies aimed at enhancing the efficacy of manganese-based and vanadium-based compounds are emphasis emphasized.Additionally,the article outlines the future prospective directions as well as strategic proposal for cathode materials in AZIBs.
文摘Artificial intelligence(AI), particularly deep learning algorithms, is gaining extensive attention for its excellent performance in image-recognition tasks. They can automatically make a quantitative assessment of complex medical image characteristics and achieve an increased accuracy for diagnosis with higher efficiency. AI is widely used and getting increasingly popular in the medical imaging of the liver, including radiology, ultrasound, and nuclear medicine. AI can assist physicians to make more accurate and reproductive imaging diagnosis and also reduce the physicians' workload. This article illustrates basic technical knowledge about AI, including traditional machine learning and deep learning algorithms, especially convolutional neural networks, and their clinical application in the medical imaging of liver diseases, such as detecting and evaluating focal liver lesions, facilitating treatment, and predicting liver treatment response. We conclude that machine-assisted medical services will be a promising solution for future liver medical care. Lastly, we discuss the challenges and future directions of clinical application of deep learning techniques.
基金the financial support from the National Natural Science Foundation of China(No.91963118)the 111 Project(No.B13013)supported by the Open Project Program of Key Laboratory of Preparation and Application of Environmental Friendly Materials(Jilin Normal University),Ministry of Education,China(No.2020004)。
文摘Graphite as a promising anode candidate of K-ion batteries(KIBs)has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials.To protect the layer structure and further boost performance,tempura-like carbon/carbon nanocomposite of graphite@pitch-derived S-doped carbon(G@PSC)is designed and prepared by a facile and low-temperature modified molten salt method.This robust encapsulation structure makes their respective advantages complementary to each other,showing mutual promotion of electrochemical performances caused by synergy effect.As a result,the G@PSC electrode is applied in KIBs,delivering impressive rate capabilities(465,408,370,332,290,and 227 m A h g^(-1)at 0.05,0.2,0.5,1,2,and 5 A g^(-1))and ultralong cyclic stability(163 m A g^(-1)remaining even after 8000 cycles at 2 A g^(-1)).On basis of ex-situ studies,the sectionalized K-storage mechanism with adsorption(pseudocapacitance caused by S doping)-intercalation(pitch-derived carbon and graphite)pattern is revealed.Moreover,the exact insights into remarkable rate performances are taken by electrochemical kinetics tests and density functional theory calculation.In a word,this study adopts a facile method to synthesize high-performance carbon/carbon nanocomposite and is of practical significance for development of carbonaceous anode in KIBs.
基金the financial support from the National Natural Science Foundation of China(91963118)the Fundamental Research Funds for the Central Universities(2412019ZD010)。
文摘Dual-ion battery(DIB) composed of graphite cathode and lithium anode is regarded as an advanced secondary battery because of the low cost, high working voltage and environmental friendliness. However,DIB operated at high potential(usually ≥ 4.5 V versus Li+/Li) is confronted with severe challenges including electrolyte decomposition on cathode interface, and structural deterioration of graphite accompanying with anions de-/intercalation, hinder its cyclic life. To address those drawbacks and preserve the DIB virtues, a feasible and scalable surface modification is achieved for the commercial graphite cathode of mesocarbon microbead. In/ex-situ studies reveal that, such an interfacial engineering facilitates and reconstructs the formation of chemically stable cathode electrolyte interphase with better flexibility alleviating the decomposition of electrolyte, regulating the anions de-/intercalation behavior in graphite with the retainment of structural integrity and without exerting considerable influence on kinetics of anions diffusion. As a result, the modified mesocarbon microbead exhibits a much-extended cycle life with high capacity retention of 82.3% even after 1000 cycles. This study demonstrates that the interface modification of electrode and coating skeleton play important roles on DIB performance improvement, providing the feasible basis for practical application of DIB owing to the green and scalable coating procedures.
基金support from the National Natural Science Foundation of China(No.91963118)the Science Technology Program of Jilin Province(No.20200201066JC)the 111 Project(No.B13013).
文摘With the increasing popularity of new en ergy electric vehicles,the dema nd for lithium-ion batteries(LIBs)has been growing rapidly,which will produce a large number of spent LIBs.Therefore,recycling of spe nt LIBs has become an urge nt task to be solved,otherwise it will inevitably lead to serious environmental pollution.Herein,a unique recycling strategy is proposed to achieve the concurrent reuse of cathode and anode in the spent graphite/LiFePO_(4) batteries.Along with such recycling process,a unique cathode composed of recycled LFP/graphite(RLFPG)with cation/anion-co-storage ability is designed for new-type dual-ion battery(DIB).As a result,the recycle-derived DIB of Li/RLFPG is established with good electrochemical performance,such as an initial discharge capacity of 117.4 mA h g^(-1) at 25 mA g^(-1) and 78% capacity retention after 1000 cycles at 100 mA g^(-1).The working mechanism of Li/RLFPG DIB is also revealed via in situ X-ray diffraction and electrode kinetics studies.This work not only presents a farreaching significance for large-scale recycling of spent LIBs in the future,but also proposed a sustainable and econo mical method to design n ew-type sec on dary batteries as recycling of spe nt LIBs.
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the National Natural Science Foundation of China,No.81860103,No.81560456,No.81660098 and No.81572438and the Outstanding Scientific Youth Fund of Guizhou Province,No.2017-5608.
文摘BACKGROUND Localized primary gastric amyloidosis is a rare disorder characterized by the extracellular deposition of insoluble fibrillary protein in the stomach and can mimic various diseases on endoscopic examination,including gastrointestinal stromal tumors,gastric cancer and ulcers.CASE SUMMARIES Here,we report a series of three cases of localized gastric amyloidosis mimicking gastric mucosa-associated lymphoid tissue(MALT)lymphoma on endoscopic examination that were evaluated over the past ten years in our hospital.The different detection times of this rare disease resulted in three completely different outcomes,indicating the strong importance of early detection,diagnosis and treatment.The difficulties encountered in making an accurate diagnosis and differential diagnosis are highlighted,and this report provides clinical experience for the diagnosis of localized primary gastric amyloidosis.CONCLUSION Localized gastric amyloidosis is a rare metabolic disease that resembles MALT lymphoma.Early detection,diagnosis and treatment of localized gastric amyloidosis result in an excellent prognosis.
基金support from the Na-tional Key R&D Program of China(Grant No.2023YFE0202000)National Natural Science Foundation of China(No.52102213)Science Technology Program of Jilin Province(No.20230101128JC).
文摘With the continuous advancement of industrialization,sodium-ion batteries(SIBs)need to operate in various challenging circumstances,particularly in extremely cold conditions.However,at ultra-low tem-peratures,the reduced ionic conductivity and sluggish Na+migration of commonly carbonate-based elec-trolytes will inevitably lead to a sharp decrease in the capacity of SIBs.Herein,we design a carboxylate ester-based electrolyte with excellent ultra-low temperature performance by straightforward cosolvent strategy.Due to the low viscosity,melting point,and sufficient ionic conductivity of the designed elec-trolyte,the resulting Na||Na_(3)V_(2)(PO_(4))_(2)O_(2)F can achieve the capacity retention of 96%(100 cycles at 0.1 C)at-40℃ and can also operate stably even at-50℃.Besides,galvanostatic intermittent titration tech-nique(GITT),ex-situ X-ray photoelectron spectroscopy(XPS),and high-resolution transmission electron microscopy(TEM)tests are employed to analyze and confirm that the carboxylate ester-based electrolyte promotes robust and uniform cathode/electrolyte interface layer formation and accelerates ion diffusion kinetics,which collectively facilitates the better low-temperature performance.In addition,the assembled hard carbon||NVPOF full cells further prove the practicability of the carboxylate ester-based electrolyte at low-temperature,which delivers high discharge capacity of 108.4 and 73.0 mAh g^(-1) at-25 and-40℃.This work affords a new avenue for designing advanced low-temperature electrolytes for SIBs.
基金financially supported by the National Natural Science Foundation of China(No.52173246)111 project(No.B13013)Shccig-Qinling Program(No.SMYJY20220574)。
文摘Hard carbon(HC)is broadly recognized as an exceptionally prospective candidate for the anodes of sodium-ion batteries(SIBs),but their practical implementation faces substantial limitations linked to precursor factors,such as reduced carbon yield and increased cost.Herein,a cost-effective approach is proposed to prepare a coal-derived HC anode with simple pre-oxidation followed by a post-carbonization process which effectively expands the d_(002)layer spacing,generates closed pores and increases defect sites.Through these modifications,the resulting HC anode attains a delicate equilibrium between plateau capacity and sloping capacity,showcasing a remarkable reversible capacity of 306.3 mAh·g^(-1)at 0.03 A·g^(-1).Furthermore,the produ ced HC exhibits fast reaction kinetics and exceptional rate performance,achieving a capacity of 289 mAh·g^(-1)at 0.1 A·g^(-1),equivalent to~94.5%of that at 0.03 A·g^(-1).When implemented in a full cell configuration,the impressive electrochemical performance is evident,with a notable energy density of 410.6 Wh·kg^(-1)(based on cathode mass).In short,we provide a straightforward yet efficient method for regulating coal-derived HC,which is crucial for the widespread use of SIBs anodes.
基金This work was supported by the National Natural Science Foundation(Nos.62325105,62227820,62071214,62288101,61571217,and 11227904)Natural Science Foundation of Jiangsu Province(BK20230020)+1 种基金the Innovation Program for Quantum Science and Technology(No.2021ZD0303401)the Jiangsu Provincial Key Laboratory of Advanced Manipulating Technique of Electromagnetic Waves.
文摘Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space explorations.To achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel,a comprehensive design of a multi-functional detector is indispensable.In this study,we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency(91.6%),high photon counting rate(1.61 Gcps),large dynamic range for resolving different photon numbers(1-24),and four-quadrant position sensing function all within one device.Furthermore,we have constructed a communication testbed to validate the advantages offered by such an architecture.Through 8-PPM(pulse position modulation)format communication experiments,we have achieved an impressive maximum data rate of 1.5 Gbps,demonstrating sensitivities surpassing previous benchmarks at respective speeds.By incorporating photon number information into error correction codes,the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps—showcasing a great potential for daylight operation scenarios.Additionally,preliminary beam tracking tests were conducted through open-loop scanning techniques,which revealed clear quantitative dependence indicating sensitivity variations based on beam location.Based on the device characterizations and communication results,we anticipate that this device architecture,along with its corresponding signal processing and coding techniques,will be applicable in future space-to-ground communication tasks.
基金financial support from the project funded by National Natural Science Foundation of China(Nos.52372188,51902090)2023 Introduction of studying abroad talent program,Science Technology Program of Jilin Province(No.20220508141RC)+5 种基金the 111 Project(No.B13013)China Postdoctoral Science Foundation(No.2019M652546)Henan Province Postdoctoral Start-Up Foundation(No.1901017)Henan Normal University Doctoral Start-Up Project Foundation,“111”project(No.D17007)Henan Center for Outstanding Overseas Scientists(No.GZS2018003)the Dalian Revitalization Talents Program(No.2022RG01)。
文摘Effective design of nanoheterostructure anode with high ion/electron migration kinetics can give electrode with superior electrochemical performance.However,the design and preparation of nanoheterostructure composites with high-capacity and long cycling life in half and pouch full cells remain a big challenge.Here,a novel micro-pore MnS/Mn_(2)SnS_(4)heterostructure nanowire were in situ encapsulated into the N and S elements co-doped amorphous carbon tubes(abbreviated as(MnS/Mn_(2)SnS_(4))@N,S-ACTs)and showed superior energy storage properties in Na-/Li-ion half cells and pouch full cells.The Na-/Li-storage capabilities improvement are attribute to the strong synergistic effect between MnS/Mn_(2)SnS_(4)heterostructure and N,S-ACTs protective layer,the former induces an local built-in electric field between Mn_(2)Sn S_(4)and MnS during charging/discharging,accelerating interfacial ion/electron diffusion dynamics,the latter effective maintains the morphology and volume evolution during Na~+/Li~+charging/discharging,achieving a long-term cycling stability(e.g.,high discharge capacity of 79.2 mAh/g with the capacity retention of 79.3%can be gained after 2200 cycles at 3 C in(Mn S/Mn_(2)Sn S_(4))@N,S-ACTs//LiFePO_(4)pouch full cells;a high capacity of~34 mAh/g at 10 C can be got with a Coulombic efficiency of 100%after 1000 cycles in pouch(Mn S/Mn_(2)Sn S_(4))@N,S-ACTs//Na_(3)V_(2)(PO_(4))_(2)O_(2)F full cells.
基金the financial support from the National Natural Science Foundation of China (No.52302222)Natural Science Foundation of Jilin Province (No.20230508177RC)+1 种基金China Postdoctoral Science Foundation (Nos.2022M720704,2023T160094)Fundamental Research Funds for the Central Universities (No.2412022QD038)。
文摘Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) are the most promising alternatives to lithium-ion batteries, and thus have drawn intensive research attention. Porous carbon materials from different precursors have been widely used as anode materials owing to their compatible storage effectiveness of both larger radii sodium and potassium ions. However, the differential bonding behaviors of Na and K ions with porous carbon-based anode are the significant one worth investigating, which could provide a clean picture of alkali ions storage mechanism. Therefore, in this work, we prepare a porous carbon network derived from sawdust(SDC) wastes, to further analyze the differences on sodium and potassium ions storage behaviors in terms of bond-forming process. It is found that, as-prepared SDC anodes could deliver stable sodium and potassium storage capacities, however, there are notable distinctions in terms of electrochemical behaviors and diffusion processes. By virtue of ex-situ XRD and Raman spectroscopy, the phase transition reaction of potassium ions could be well-observed, and the results shows that the multiple intercalated compounds was formed in SDC network during ions insertion, further resulting in slower diffusion kinetics and larger resistance compared to non-bonded process of sodium ions storage. This study provides more insights into the differences between sodium and potassium ions storage, as well as the energy storage mechanism of porous carbon as anodes for secondary batteries.
基金financially supported by the National Natural Science Foundation of China(No.52173246)Natural Science Foundation of Jilin Province(No.20220508141RC)+3 种基金DoubleThousand Talents Plan of Jiangxi Province(No.jxsq2023102005)111 Project(No.B13013)Education Department of Jilin Province(No.JJKH20221154KJ)Shccig-Qinling Program。
文摘Nowadays,lithium-ion batteries(LIBs)play a crucial role in modern society in the aspect of portable electronic devices and large-scale smart grids.However,the current performance of lithium-ion batteries has been unable to meet the growing expectations of society and scientific community.Herein,we have synthetically investigated availability of 2D Ni-TABQ monolayer as anode based on DFT for LIBs applications.Our findings have demonstrated that 2D Ni-TABQ monolayer is a semiconductor with a small band gap of 0.2 eV,which suggest that the electronic property of 2D Ni-TABQ monolayer would take place an evident shift from semiconductor property to metallic property after Li adsorption.Furthermore,we checked the stability of 2D Ni-TABQ monolayer and investigated the viability of exfoliation from bulk multilayer Ni-TABQ to form 2D Ni-TABQ monolayer in the light of exfoliation energy and binding energy.We continuously studied electrochemical properties of 2D Ni-TABQ monolayer with respect of theoretical specific capacity,Li-ion diffusion barriers and open-circuit voltage.During the charging process,2D Ni-TABQ monolayer can achieve a high specific capacity of 722 m Ah/g with an open-circuit voltage range from 1.12 V to 0.22 V.These aforementioned results make the 2D Ni-TABQ monolayer a promising anode for LIBs.
基金supported by the National Natural Science Foundation of China(22279075)Shandong Provincial Natural Science Foundation(ZR2020YQ09).
文摘As the need for energy storage devices escalates,aqueous zincion batteries(ZIBs)have risen as a promising alternative to the widely used Li-ion batteries,offering intrinsic safety,environmental compatibility,and cost advantages,positioning them as attractive energy storage systems for the future[1,2].However,challenges such as dendrite growth on Zn anodes,stemming from uneven electric fields on the surface and active water side reactions,compromise cycling stability and lifespan,posing significant hurdles for the practical application of ZIBs[3,4].To mitigate these issues,strategies like electrolyte optimization,artificial solid electrolyte interphase(SEI)layers,and current collector modifications have been proposed[5,6].Nevertheless,most long-cycle experiments are conducted at low current densities and deposition capacities,with high current density and capacity operations typically lasting less than 1000 h[7].
基金supported by the National Natural Science Foundation of China(No.52302222)the Natural Science Foundation of Jilin Province(No.20220508141RC)+3 种基金the Education Department of Jilin Provinces(No.JJKH20241409KJ)the 111 Project(B13013)China Postdoctoral Science Foundation(2023T160094)the Fundamental Research Funds for the Central Universities(2412022QD038)。
文摘Acid hydrogen evolution reaction(HER)is a critical energy conversion process,which is significantly important in hydrogen energy manufacturing and storage[1].Although the performance of noble metal platinum(Pt)-based catalysts in acidic HER is well known,the challenges are high cost,limited reserves,poor stability,and susceptibility to toxic substances[2].Therefore,it is urgent to design and manufacture acidic HER catalysts with high reactivity,high stability,and low cost.
基金supported by the National Natural Science Foundation of China(91963118)the Fundamental Research Funds for the Central Universities(2412019ZD010).
文摘One main challenge for phosphate cathodes in sodium-ion batteries(SIBs)is to increase the working voltage and energy density to promote its practicability.Herein,an advanced Na3V2(PO4)2F3@C cathode is prepared successfully for sodium-ion full cells.It is revealed that,carbon coating can not only enhance the electronic conductivity and electrode kinetics of Na3V2(PO4)2F3@C and inhibit the growth of particles(i.e.,shorten the Na^+-migration path),but also unexpectedly for the first time adjust the dis-/charging plateaux at different voltage ranges to increase the mean voltage(from 3.59 to 3.71 V)and energy density from 336.0 to 428.5 Wh kg^-1 of phosphate cathode material.As a result,when used as cathode for SIBs,the prepared Na3V2(PO4)2F3@C delivers much improved electrochemical properties in terms of larger specifc capacity(115.9 vs.93.5 mAh g^-1),more outstanding high-rate capability(e.g.,87.3 vs.60.5 mAh g^-1 at 10 C),higher energy density,and better cycling performance,compared to pristine Na3V2(PO4)2F3.Reasons for the enhanced electrochemical properties include ionicity enhancement of lattice induced by carbon coating,improved electrode kinetics and electronic conductivity,and high stability of lattice,which is elucidated clearly through the contrastive characterization and electrochemical studies.Moreover,excellent energy-storage performance in sodium-ion full cells further demonstrate the extremely high possibility of Na3V2(PO4)2F3@C cathode for practical applications.
基金the National Natural Science Foundation of China(No.91963118)the Science Technology Program of Jilin Province(No.20200201066JC)+1 种基金the“13th Five-Year”Science and Technology Research from the Education Department of Jilin Province(No.JJKH20201179KJ)the 111 Project(No.B13013)。
文摘In recent years,sodium-ion batteries(SIBs)have been considered as one of the most promising alternatives to lithium-ion batteries(LIBs).Here,a new Na-super-ionic conductor(NASICON)cathode material Na Fe_(2)PO_(4)(SO_(4))_(2)is successfully prepared through solid state method for SIBs.While the poor electronic conductivity of iron-based materials results in its poor rate and cycle performance.Then the electrochemical is effectively promoting via Ca^(2+)doping.Na_(0.84)Ca_(0.08)Fe_(2)PO_(4)(SO_(4))_(2)have achieved considerable electrochemical properties.The first discharge specific capacity is 121.6 m A h g^(-1)at 25 m A g^(-1)with the voltage platform(-3.1 V)corresponding to Fe^(2+/3+).After 100 cycles,the capacity retention is 55.1%.The excellent electrochemical performance is caused by some Na^(+)is substituted by Ca^(2+)and leading to the fast sodium kinetics,which is well proved by the powder X-ray diffraction pattern and well corresponding to the galvanostatic intermittent titration technique and cyclic voltammetry testing result(the diffusivity values are around at 10^(-12)cm^(2)s^(-1)).
基金supported by the National Natural Science Foundation of China(Nos.52173246,91963118,and 52102213)the Science Technology Program of Jilin Province(No.20200201066JC)。
文摘Due to the serious imbalance between demand and supply of lithium,lithium extraction from brine has become a research hotspot.With the demand for power lithium-ion batteries(LIBs)increased rapidly,a large number of spent LiFePO_(4)power batteries have been scrapped and entered the recycling stage.Herein,a novel and efficient strategy is proposed to extract lithium from brine by directly reusing spent LiFePO_(4)powder without any treatment.Various electrochemical test results show that spent LiFePO_(4)electrode has appropriate lithium capacity(14.62 mg_(Li)/g_(LiFePO_(4))),excellent separation performance(α_(Li-Na)=210.5)and low energy consumption(0.768 Wh/g_(Li))in electrochemical lithium extraction from simulated brine.This work not only provides a novel idea for lithium extraction from brine,but also develops an effective strategy for recycling spent LIBs.The concept of from waste to wealth is of great significance to the development of recycling the spent batteries.
基金111 Project,Grant/Award Number:B13013Education Department of Jilin Province,Grant/Award Number:.JJKH20201179KJ+1 种基金Science Technology Program of Jilin Province,Grant/Award Number:20200201066JCNational Natural Science Foundation of China,Grant/Award Number:91963118。
文摘As a cathode for sodium-ion batteries(SIBs),Na3V2(PO4)2F3(NVPF)with 3D open framework is a promising candidate due to its high working voltage and large theoretical capacity.However,the severe capacity degradation and poor rate capability hinder its practical applications.The present study demonstrated the optimization of Na-storage performance of NVPF via delicate lattice modulation.Aliovalent substitution of V^(3^(+))at Na^(+)in NVPF induces the generation of electronic defects and expansion of Na^(+)-migration channels,resulting in the enhancement in electronic conductivity and acceleration of Na^(+)-migration kinetics.It is disclosed that the formed stronger Na O bonds with high ionicity than V O bonds lead to the significant increase in structural stability and ionicity in the Na^(+)-substituted NVPF(NVPF-Nax).The aforementioned effects of Na^(+)substitution achieve the unprecedented electrochemical performance in the optimized Na_(3.14)V1.93Na0.07(PO_(4))_(2)F_(3)(NVPF-Na_(0.07)).As a result,NVPF-Na0.07 delivers a high-rate capability(77.5 mAh g^(−1)at 20 C)and ultralong cycle life(only 0.027%capacity decay per cycle over 1000 cycles at 10 C).Sodium-ion full cells are designed using NVPF-Na0.07 as cathode and Se@reduced graphene oxide as anode.The full cells exhibit excellent wide-temperature electrochemical performance from−25 to 25C with an outstanding rate capability(96.3 mAh g^(−1)at 20 C).Furthermore,it delivered an excellent cycling performance over 300 cycles with a capacity retention exceeding 90%at 0.5 C under different temperatures.This study demonstrates a feasible strategy for the development of advanced cathode materials with excellent electrochemical properties to achieve high-efficiency energy storage.