Sodium-ion hybrid capacitors(SICs)offer inherent energy-power synergy but are constrained by mismatched kinetics and life spans between the anode and cathode materials.Two-dimensional MoS_(2)@C composites demonstrate ...Sodium-ion hybrid capacitors(SICs)offer inherent energy-power synergy but are constrained by mismatched kinetics and life spans between the anode and cathode materials.Two-dimensional MoS_(2)@C composites demonstrate excellent kinetics and structural stability,thanks to the built-in electric field of the carbon heterostructure and its adaptability to volume changes.Yet,the carbon shell imposes a physical barrier to interfacial Na^(+)diffusion,while deep discharge induces the formation of crystalline Na_(2)S,accompanied by severe volumetric expansion and sluggish reversibility—factors that accelerate capacity fading and structural degradation.To address these challenges,a trace-level Ni doping strategy is introduced,enabling precise modulation of the composite's interlayer structure,electronic configuration,and reaction pathway.Ni incorporation expands the MoS_(2) interlayer spacing,reconstructs short-range ordered nanocrystals within a hierarchically porous network,and promotes Na^(+)diffusion by weakening interlayer van der Waals forces.Orbital hybridization between Ni-3d and Mo-4d/S-3p states enhances electronic conductivity and reduces charge transfer resistance.Critically,Ni doping enhances electron transfer from Ni to sulfur,which weakens Na–S bonds and promotes the formation of amorphous Na_(2)S,thereby suppressing crystalline Na_(2)S and enabling a reversible MoS_(2)/Na_(2)S conversion mechanism for improved structural stability and cycling performance.As a result,the optimized MoS_(2)-Ni@C anode delivers a high reversible capacity of 334 mAh g^(-1)at 10 A g^(-1)with 68%retention after 10,000 cycles.When assembled into a SIC device(MoS_(2)-Ni@C//AC),it achieves an energy density of 135 Wh kg^(-1)at a power density of 60.8 kW kg^(-1)(based on anode mass),with 76%retention over 3,000 cycles.展开更多
Modern power electronics,from electric vehicles to renewable energy systems,demand capacitors that can reliably store high energy at elevated temperatures.Polymer dielectrics are widely used in capacitors due to their...Modern power electronics,from electric vehicles to renewable energy systems,demand capacitors that can reliably store high energy at elevated temperatures.Polymer dielectrics are widely used in capacitors due to their high breakdown strength and ease of processing,but they traditionally suffer from poor energy density at high temperatures[1-4].展开更多
Lithium-ion capacitors(LICs) hold promise as next-generation energy storage devices due to the synergy of the advantageous features of lithium-ion batteries(LIBs) and supercapacitors(SCs).Recently,the use of nanostruc...Lithium-ion capacitors(LICs) hold promise as next-generation energy storage devices due to the synergy of the advantageous features of lithium-ion batteries(LIBs) and supercapacitors(SCs).Recently,the use of nanostructured conjugated carboxylate organic anode materials in LICs has attracted tremendous attention due to their high capacity,excellent capacitive behavior,design flexibility,and environmental friendliness.Nevertheless,no studies have reported the use of non-conjugated organic compounds in LICs.In this study,we report for the first time that non-conjugated adipamide(ADIPAM) nanocrystals fabricated using a dissolution-recrystallization self-assembly technique serve as an excellent anode material for LICs.The unique ADIPAM nanocrystals-PVDF-Super P conductive integrated network architecture accelerates Li^(+) ion and electron diffusion and enhances lithium storage capability.Consequently,ADIPAM electrodes exhibit a high capacity of 705.8 mAh/g,exceptional cycling stability(308 mAh/g after 2100cycles at 5 A/g),and remarkable rate capability.Furthermore,a LIC full cell comprising the ADIPAM anode with a porous activated carbon cathode demonstrates a wide working window(4.5 V),high energy density(238.3 Wh/kg),and superb power density(22,500 W/kg).We believe this work may introduce a new approach to the design of non-conjugated organic materials for LICs.展开更多
Carbon superstructures with multiscale hierarchies and functional attributes represent an appealing cathode candidate for zinc hybrid capacitors,but their tailor-made design to optimize the capacitive activity remains...Carbon superstructures with multiscale hierarchies and functional attributes represent an appealing cathode candidate for zinc hybrid capacitors,but their tailor-made design to optimize the capacitive activity remains a confusing topic.Here we develop a hydrogen-bond-oriented interfacial super-assembly strategy to custom-tailor nanosheet-intertwined spherical carbon superstructures(SCSs)for Zn-ion storage with double-high capacitive activity and durability.Tetrachlorobenzoquinone(H-bond acceptor)and dimethylbenzidine(H-bond donator)can interact to form organic nanosheet modules,which are sequentially assembled,orientally compacted and densified into well-orchestrated superstructures through multiple H-bonds(N-H···O).Featured with rich surface-active heterodiatomic motifs,more exposed nanoporous channels,and successive charge migration paths,SCSs cathode promises high accessibility of built-in zincophilic sites and rapid ion diffusion with low energy barriers(3.3Ωs-0.5).Consequently,the assembled Zn||SCSs capacitor harvests all-round improvement in Zn-ion storage metrics,including high energy density(166 Wh kg-1),high-rate performance(172 m Ah g^(-1)at 20 A g^(-1)),and long-lasting cycling lifespan(95.5%capacity retention after 500,000 cycles).An opposite chargecarrier storage mechanism is rationalized for SCSs cathode to maximize spatial capacitive charge storage,involving high-kinetics physical Zn^(2+)/CF_(3)SO_(3)-adsorption and chemical Zn^(2+)redox with carbonyl/pyridine groups.This work gives insights into H-bond-guided interfacial superassembly design of superstructural carbons toward advanced energy storage.展开更多
Transition metal selenides as sodium-ion hybrid capacitor(SIHC)anodes still suffer from amorphization difficulties and capacity degradation triggered by polyselenide dissolution.Herein,an atomistic amorphous strategy ...Transition metal selenides as sodium-ion hybrid capacitor(SIHC)anodes still suffer from amorphization difficulties and capacity degradation triggered by polyselenide dissolution.Herein,an atomistic amorphous strategy is proposed to construct adjacent Nb-Nb diatomic pairs with Se/O-coordination(Se4-Nb2-O2)in N-doped carbon-confined amorphous selenide clusters(a-Nb-Se/O@NC).Synergistic carbon confinement and hydrothermal oxygenation induce amorphization of Nb–Se bonds,eliminating crystalline rigidity while creating isotropic dual-ion transport channels and high-density active sites enriched with dangling bonds,thereby enhancing structural integrity and Na+storage capacity.The unique Se/O-coordinated Nb-Nb diatomic configuration establishes an electron-delocalized system,where the low electronegativity of Se counterbalances electron withdrawal from coordinated O at Nb centers.These strengthen d-p orbital hybridization,reduce Na+adsorption energy,and optimize charge transfer pathways and reaction kinetics in the amorphous clusters.Electrochemical tests reveal that the a-Nb-Se/O@NC anode delivers a high reversible capacity of 312.57 mAh g^(−1)and exceptional cyclic stability(103%capacity retention)after 5000 cycles at 10.0 A g^(−1).Assembled SIHCs achieve outstanding energy/power densities(207.1 Wh kg^(−1)/18966 W kg^(−1)),surpassing most amorphous and crystalline counterparts.This work provides methodological insights for the design of electrodes in high-power storage devices through atomic modulation and electronic optimization of amorphous selenides.展开更多
Hybrid Na-ion capacitors(NICs)have received considerable interests owing to their low-cost,high-safety,and rapidly charging energy-storage characteristics.The NICs are composed of a capacitor-type cathode and a batter...Hybrid Na-ion capacitors(NICs)have received considerable interests owing to their low-cost,high-safety,and rapidly charging energy-storage characteristics.The NICs are composed of a capacitor-type cathode and a battery-type anode.The major challenge for NICs is to search for suitable electrode materials to overcome the sluggish diffusion of Na^(+)in the anode.Herein,ultrafine vanadium sulfide is encapsulated in carbon fiber(V_(3)S_(4)@CNF)as a self-supported electrode by electrospinning and in situ sulfurization.The carbon cladding and one-dimensional(ID)nanofiber network-like structure could alleviate the volume expansion of V_(3)S_(4)during Na^(+)de-/intercalation process.Consequently,the V_(3)S_(4)@CNF anode exhibited a pseudocapacitive sodium storage in terms of large Na^(+)-storage capacity(476 mAh·g^(-1)at 0.1A·g^(-1)),high-rate capability(290 mAh·g^(-1)at 20.0 A·g^(-1))and excellent cycling stability(95%capacity retention for1500 cycles at 2.0 A·g^(-1))in Na half-cells.By employing V_(3)S_(4)@CNF as the anode and the activated carbon(AC)cathode,the as-assembled NICs could deliver a high energy density of 110 Wh·kg^(-1)at a power density of200 W·kg^(-1).Even at a high power of 10,000 W·kg^(-1),the specific energy is still up to 42 Wh·kg^(-1).展开更多
Practical applications of diverse flexible wearable electronics require electrochemical energy storage(EES)devices with multiple configurations.Moreover,to fabricate flexible EES devices with high energy density and s...Practical applications of diverse flexible wearable electronics require electrochemical energy storage(EES)devices with multiple configurations.Moreover,to fabricate flexible EES devices with high energy density and stability,organic integration from electrode design to device assembly is required.To address these challenges,a free-standing reduced graphene oxide(rGO)/carbon film with a unique sandwich structure has been designed via the assistance of vacuum-assistant filtration for lithium-ion capacitors(LICs).The graphene acts as not only a binder to construct a three-dimensional conductive network but also an active material to provide additional capacitive lithium storage sites,thus enabling fast ion/electron transport and improving the capacity.The designed rGO/hard carbon(rGO/HC)and rGO/activated carbon(rGO/AC)free-standing films exhibit enhanced specific capacities(513.7 mA h g^(-1)for rGO/HC and 102.8 mA h g^(-1)for rGO/AC)and excellent stability.Moreover,the integrated flexible quasi-solid-state rGO/AC//rGO/HC LIC devices possess a maximum energy density of 138.3 Wh kg^(-1),a high power density of 11 kW kg^(-1),and improved cycling performance(84.4%capacitance maintained after 10,000 cycles),superior to the AC//HC LIC(43.5%retention).Such a strategy enlightens the development of portable flexible LICs.展开更多
Aqueous zinc ion hybrid capacitors(ZIHCs)hold great potential for large-scale energy storage applications owing to their high safety and low cost,but suffer from low capacity and energy density.Herein,pyridinic nitrog...Aqueous zinc ion hybrid capacitors(ZIHCs)hold great potential for large-scale energy storage applications owing to their high safety and low cost,but suffer from low capacity and energy density.Herein,pyridinic nitrogen enriched porous carbon(nPC)was successfully synthesized via the growth,subsequent annealing and acid etching of bimetal organic frameworks for high capacity and safe ZIHCs with exceptional rate capability.Benefiting from the mesopores for easy ion diffusion,high electrical conductivity enabled by in-situ grown carbon nanotubes matrix and residual metal Co nanoparticles for fast electron transfer,sufficient micropores and high N content(8.9 at%)with dominated pyridinic N(54%)for enhanced zinc ion storage,the resulting nPC cathodes for ZIHCs achieved high capacities of 302 and137 m Ah g^(-1) at 1 and 18 A g^(-1),outperforming most reported carbon based cathodes.Theoretical results further disclosed that pyridinic N possessed larger binding energy of-4.99 eV to chemically coordinate with Zn2+than other N species.Moreover,quasi-solid-state ZIHCs with gelatin based gel electrolytes exhibited high energy density of 157.6 Wh kg^(-1) at 0.69 kW kg^(-1),high safety and mechanical flexibility to withstand mechanical deformation and drilling.This strategy of developing pyridinic nitrogen enriched porous carbon will pave a new avenue to construct safe ZIHCs with high energy densities.展开更多
Nanosized nickel oxide powders were prepared by thermal decomposition of the nickel citrate gel precursors. The thermal decomposition and powder materials derived from calcination of these gel precursors with various ...Nanosized nickel oxide powders were prepared by thermal decomposition of the nickel citrate gel precursors. The thermal decomposition and powder materials derived from calcination of these gel precursors with various ratios of citric acid （CA） to nickel at different temperatures and times were characterized by thermal analysis （TG/DTA）, scanning electron microscopy （SEM）, x-ray diffraction （XRD）, and measurement of specific surface area （BET） with porosity analyses. The optimized processing conditions of calcination temperature 400℃ for 1 hour with the CA/Ni ratio of 1.2, were determined to produce the nanosized nickel oxide pow- ders with a high specific surface area of 181 m^2/g, nanometer particle sizes of 15-25 nm, micro-pore diameter distribution between 4-10 nm. The capacitance characteristics of the nanosized nickel oxide electrode in various concentrations of KOH solutions were studied by the cyclic voltammetry （CV） exhibiting both a double-layer capacitance and a faradaic pseudocapacitance. The nanosized nickel oxide electrode shows a high cyclic stability and is promising for high performance electrochemical capacitors.展开更多
A new sol-gel process for the preparation of ultrafine nickel hydroxideelectrode materials was developed. The composite electrodes consisting of carbon nanotubes andNi(OH)_2 were developed by mixing the hydroxide and ...A new sol-gel process for the preparation of ultrafine nickel hydroxideelectrode materials was developed. The composite electrodes consisting of carbon nanotubes andNi(OH)_2 were developed by mixing the hydroxide and carbon nanotubes together in different massratios. In order to enhance energy density, a combined type pseudocapacitor/electric double layercapacitor was considered and its electrochemical properties were characterized by cyclic voltammetryand dc charge/discharge test. The combined capacitor shows excellent capacitor behavior with anoperating voltage up to 1.6 V in KOH aqueous electrolyte. Stable charge/discharge behaviors wereobserved with much higher specific capacitance values of 24 F/g compared with that of EDLC (12 F/g)by introducing 60 percent Ni(0H)_2 in the anode material. By using the modified anode of aNi(OH)_2/carbon nanotubes composite electrode, the specific capacitance of the cell was lesssensitive to discharge current density compared with that of the capacitor employing pure nickelhydroxide as anode. The combined capacitor in this study exhibits high energy density and stablepower characteristics.展开更多
Free-standing covalent organic framework(COFs)nanofilms exhibit a remarkable ability to rapidly intercalate/de-intercalate Li^(+) in lithium-ion batteries,while simultaneously exposing affluent active sites in superca...Free-standing covalent organic framework(COFs)nanofilms exhibit a remarkable ability to rapidly intercalate/de-intercalate Li^(+) in lithium-ion batteries,while simultaneously exposing affluent active sites in supercapacitors.The development of these nanofilms offers a promising solution to address the persistent challenge of imbalanced charge storage kinetics between battery-type anode and capacitor-type cathode in lithium-ion capacitors(LICs).Herein,for the first time,custom-made COFBTMB-TP and COFTAPB-BPY nanofilms are synthesized as the anode and cathode,respectively,for an all-COF nanofilm-structured LIC.The COFBTMB-TP nanofilm with strong electronegative–CF3 groups enables tuning the partial electron cloud density for Li^(+) migration to ensure the rapid anode kinetic process.The thickness-regulated cathodic COFTAPB-BPY nanofilm can fit the anodic COF nanofilm in the capacity.Due to the aligned 1D channel,2D aromatic skeleton and accessible active sites of COF nanofilms,the whole COFTAPB-BPY//COFBTMB-TP LIC demonstrates a high energy density of 318 mWh cm^(−3) at a high-power density of 6 W cm^(−3),excellent rate capability,good cycle stability with the capacity retention rate of 77%after 5000-cycle.The COFTAPB-BPY//COFBTMB-TP LIC represents a new benchmark for currently reported film-type LICs and even film-type supercapacitors.After being comprehensively explored via ex situ XPS,7Li solid-state NMR analyses,and DFT calculation,it is found that the COFBTMB-TP nanofilm facilitates the reversible conversion of semi-ionic to ionic C–F bonds during lithium storage.COFBTMB-TP exhibits a strong interaction with Li^(+) due to the C–F,C=O,and C–N bonds,facilitating Li^(+) desolation and absorption from the electrolyte.This work addresses the challenge of imbalanced charge storage kinetics and capacity between the anode and cathode and also pave the way for future miniaturized and wearable LIC devices.展开更多
Cobalt selenide(CoSe_(2))has garnered considerable attention as a prospective anode candidate for advanced lithium-ion storage,prompting comprehensive investigations.However,CoSe_(2)-based anodes usually suffer from s...Cobalt selenide(CoSe_(2))has garnered considerable attention as a prospective anode candidate for advanced lithium-ion storage,prompting comprehensive investigations.However,CoSe_(2)-based anodes usually suffer from significant volume variation upon lithiation leading to unsatisfactory cycling stability.Herein,a versatile synthesis route is proposed for the in-situ fabrication of CoSe2nanoparticles embedded in N-dope carbon skeleton(CoSe_(2)@NC)through annealing treatment and selenization of a metal–organic framework-derived(MOF)precursor.The N-doped carbon derived from the MOF serves not only as an excellent conductive substrate but also as a confined reactor,effectively inhibiting the structural instability and alleviating the inevitable volume change of CoSe_(2).Owing to their unique nanostructure,the as-prepared CoSe_(2)@NC exhibits a high capacity of 745.9mAh·g^(-1)at 0.1 A·g^(-1),while maintaining excellent rate capability and an impressive lifespan.Furthermore,the assembled lithium-ion capacitor(LIC)based on CoSe_(2)@NC demonstrates an energy density of 130Wh·kg^(-1),a power density of 24.6 kW·kg^(-1),and remarkable capacity retention of 90.8%after 8000 cycles.These results highlight the great potential of CoSe_(2)@NC for practical applications.展开更多
Nickel–cobalt tellurides are deemed as promising electrode materials for energy storage devices due to their superior conductivity and theoretical specific capacitance.Here,NiCoTe_(2)was successfully fabricated on ca...Nickel–cobalt tellurides are deemed as promising electrode materials for energy storage devices due to their superior conductivity and theoretical specific capacitance.Here,NiCoTe_(2)was successfully fabricated on carbon cloth by facile electrodeposition and hydrothermal synthesis,which can directly serve as a binderless electrode.The NiCoTe_(2)with interconnected nanosheet arrays on a conductive carbon substrate showed a high specific capacitance(924 F/g at 1 A/g)and robust longterm cycling stability(89.6%retention after 5000 cycles).In addition,the assembled NiCoTe_(2)//activiated carbon hybrid supercapacitor achieved a high energy and power density with a short charging time(42.26 Wh/kg at a power density of 760.96 W/kg).This work provides a novel idea to produce bimetallic nickel–cobalt telluride nanosheet array electrodes for high-performance hybrid supercapacitors.展开更多
There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of t...There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of traditional rechargeable batteries with the superior power density and long life of supercapacitors(SCs).Nevertheless,the development of LICs is still hampered by limited kinetic processes and capacity mismatch between the cathode and anode.Metal-organic frameworks(MOFs)and their derivatives have received significant attention because of their extensive specific surface area,different pore structures and topologies,and customizable functional sites,making them compelling candidate materials for achieving high-performance LICs.MOF-derived carbons,known for their exceptional electronic conductivity and large surface area,provide improved charge storage and rapid ion transport.MOF-derived transition metal oxides contribute to high specific capacities and improved electrochemical stability.Additionally,MOF-derived metal compounds/carbons provide combined effects that increase both the capacitive and Faradaic reactions,leading to a superior overall performance.The review begins with an overview of the fundamental principles of LICs,followed by an exploration of synthesis strategies and ligand selection for MOF-based composite materials.It then analyzes the advantages of original MOFs and their derived materials,such as carbon materials and metal compounds,in enhancing LIC performance.Finally,the review discusses the major challenges faced by MOFs and their derivatives in LIC applications and offers future research directions and recommendations.展开更多
A correlation-based digital background calibration algorithm for pipelined Analog-to- Digital Converters (ADCs) is presented in this paper. The merit of the calibration algorithm is that the main errors information, w...A correlation-based digital background calibration algorithm for pipelined Analog-to- Digital Converters (ADCs) is presented in this paper. The merit of the calibration algorithm is that the main errors information, which include the capacitor mismatches and residue amplifier distortion, are extracted integrally. A modified 1st pipelined stage is adopted to solve the signal overflow caused by the Pseudo-random Noise (PN) sequences. Behavioral simulation results verify the effectiveness of the algorithm. It improves the Signal-to-Noise-plus-Distortion Ratio (SNDR) and Spurious-Free-Dynamic-Range (SFDR) of the pipelined ADC from 41.8 dB to 78.3 dB and 55.6 dB to 98.6 dB, respectively, which is comparable to the prior arts.展开更多
The large variability in wind output power can adversely impact local loads that are sensitive to poor power quality. To mitigate large swings in power, the wind turbine output power can be conditioned by using a smal...The large variability in wind output power can adversely impact local loads that are sensitive to poor power quality. To mitigate large swings in power, the wind turbine output power can be conditioned by using a small energy buffer. A power conditioner is developed to smooth the wind power output by utilizing the energy of an electrochemical capacitor, or ultracapacitor. The conditioner is based on a single phase voltage source inverter connected between the grid inter-connection point and the ultracapacitor. The VSI shunt inverter injects or absorbs active power from the line to smooth the wind power output by utilizing the short term storage capabilities of the ultracapacitor. The ultracapacitor is connected to the DC link through a bidirectional DC-DC converter. The bidirectional DC-DC converter and VSI are constructed and field tested on a Skystream 3.7 wind turbine installed at the Missouri University of Science & Technology.展开更多
Potassium-ion capacitors(KICs)are promising for sustainable and eco-friendly energy storage technologies,yet their slow reaction kinetics and poor cyclability induced by large K-ion size are a major obstacle toward pr...Potassium-ion capacitors(KICs)are promising for sustainable and eco-friendly energy storage technologies,yet their slow reaction kinetics and poor cyclability induced by large K-ion size are a major obstacle toward practical applications.Herein,by employing black phosphorus nanosheets(BPNSs)as a typical high-capacity anode material,we report that BPNS anodes armored with an ultrathin oriented-grown metal–organic-framework(MOF)interphase layer(BPNS@MOF)exhibit regulated potassium storage behavior for highperformance KICs.The MOF interphase layers as protective layer with ordered pores and high chemical/mechanical stability facilitate K ion diffusion and accommodate the volume change of electrode,beneficial for improved reaction kinetics and enhanced cyclability,as evidenced by substantial characterizations,kinetics analysis and DFT calculations.Consequently,the BPNS@MOF electrode as KIC anodes exhibits outstanding cycle performance outperforming most of the reported state-of-art KICs so far.展开更多
Using the diluted S1813 UV photoresist as a sacrificial layer, we successfully fabricate a superconducting suspended parallel-plate capacitor, in which the top layer of aluminum film acts as a membrane mechanical reso...Using the diluted S1813 UV photoresist as a sacrificial layer, we successfully fabricate a superconducting suspended parallel-plate capacitor, in which the top layer of aluminum film acts as a membrane mechanical resonator. Together with a superconducting octagonal spiral inductor, this parallel-plate capacitor constitutes a superconducting microwave resonator. At m K temperature, the transmission characteristic and spectrum of the microwave resonator are measured.Sideband frequencies caused by the vibration of the membrane mechanical resonator are clearly demonstrated. By downconverting with a mixer, the dependence of fundamental frequency and its harmonics on the input microwave power are clearly demonstrated, which is consistent with the numerical simulation.展开更多
基金supported by the Carbon Emission Peak and Neutrality of Jiangsu Province(BE2022031-4)the National Natural Science Foundation of China(Key Program)(52131306,52122209,52403001)+1 种基金the Project on National Key R&D Program of China(2021YFB2400400)the Cultivation Program for The Excellent Doctoral Dissertation of Nanjing Tech University。
文摘Sodium-ion hybrid capacitors(SICs)offer inherent energy-power synergy but are constrained by mismatched kinetics and life spans between the anode and cathode materials.Two-dimensional MoS_(2)@C composites demonstrate excellent kinetics and structural stability,thanks to the built-in electric field of the carbon heterostructure and its adaptability to volume changes.Yet,the carbon shell imposes a physical barrier to interfacial Na^(+)diffusion,while deep discharge induces the formation of crystalline Na_(2)S,accompanied by severe volumetric expansion and sluggish reversibility—factors that accelerate capacity fading and structural degradation.To address these challenges,a trace-level Ni doping strategy is introduced,enabling precise modulation of the composite's interlayer structure,electronic configuration,and reaction pathway.Ni incorporation expands the MoS_(2) interlayer spacing,reconstructs short-range ordered nanocrystals within a hierarchically porous network,and promotes Na^(+)diffusion by weakening interlayer van der Waals forces.Orbital hybridization between Ni-3d and Mo-4d/S-3p states enhances electronic conductivity and reduces charge transfer resistance.Critically,Ni doping enhances electron transfer from Ni to sulfur,which weakens Na–S bonds and promotes the formation of amorphous Na_(2)S,thereby suppressing crystalline Na_(2)S and enabling a reversible MoS_(2)/Na_(2)S conversion mechanism for improved structural stability and cycling performance.As a result,the optimized MoS_(2)-Ni@C anode delivers a high reversible capacity of 334 mAh g^(-1)at 10 A g^(-1)with 68%retention after 10,000 cycles.When assembled into a SIC device(MoS_(2)-Ni@C//AC),it achieves an energy density of 135 Wh kg^(-1)at a power density of 60.8 kW kg^(-1)(based on anode mass),with 76%retention over 3,000 cycles.
文摘Modern power electronics,from electric vehicles to renewable energy systems,demand capacitors that can reliably store high energy at elevated temperatures.Polymer dielectrics are widely used in capacitors due to their high breakdown strength and ease of processing,but they traditionally suffer from poor energy density at high temperatures[1-4].
基金supported by the National Natural Science Foundation of China(Nos.22309022,92372101)the Project of Natural Science Foundation of Chongqing,China(Nos.CSTB2023NSCQMSX0405,CSTB2023NSCQ-LZX0039)+2 种基金the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJQN202201104)the Key Project of Chongqing Technology Innovation and Application Development(No.CSTB2023TIADKPX0091)the China Postdoctoral Science Foundation(No.2023M742888)。
文摘Lithium-ion capacitors(LICs) hold promise as next-generation energy storage devices due to the synergy of the advantageous features of lithium-ion batteries(LIBs) and supercapacitors(SCs).Recently,the use of nanostructured conjugated carboxylate organic anode materials in LICs has attracted tremendous attention due to their high capacity,excellent capacitive behavior,design flexibility,and environmental friendliness.Nevertheless,no studies have reported the use of non-conjugated organic compounds in LICs.In this study,we report for the first time that non-conjugated adipamide(ADIPAM) nanocrystals fabricated using a dissolution-recrystallization self-assembly technique serve as an excellent anode material for LICs.The unique ADIPAM nanocrystals-PVDF-Super P conductive integrated network architecture accelerates Li^(+) ion and electron diffusion and enhances lithium storage capability.Consequently,ADIPAM electrodes exhibit a high capacity of 705.8 mAh/g,exceptional cycling stability(308 mAh/g after 2100cycles at 5 A/g),and remarkable rate capability.Furthermore,a LIC full cell comprising the ADIPAM anode with a porous activated carbon cathode demonstrates a wide working window(4.5 V),high energy density(238.3 Wh/kg),and superb power density(22,500 W/kg).We believe this work may introduce a new approach to the design of non-conjugated organic materials for LICs.
基金financially supported by the National Natural Science Foundation of China(Nos.22272118,22172111,and 22309134)the Science and Technology Commission of Shanghai Municipality,China(Nos.22ZR1464100,20ZR1460300,and 19DZ2271500)+2 种基金the China Postdoctoral Science Foundation(2022M712402),the Shanghai Rising-Star Program(23YF1449200)the Zhejiang Provincial Science and Technology Project(2022C01182)the Fundamental Research Funds for the Central Universities(2023-3-YB-07)。
文摘Carbon superstructures with multiscale hierarchies and functional attributes represent an appealing cathode candidate for zinc hybrid capacitors,but their tailor-made design to optimize the capacitive activity remains a confusing topic.Here we develop a hydrogen-bond-oriented interfacial super-assembly strategy to custom-tailor nanosheet-intertwined spherical carbon superstructures(SCSs)for Zn-ion storage with double-high capacitive activity and durability.Tetrachlorobenzoquinone(H-bond acceptor)and dimethylbenzidine(H-bond donator)can interact to form organic nanosheet modules,which are sequentially assembled,orientally compacted and densified into well-orchestrated superstructures through multiple H-bonds(N-H···O).Featured with rich surface-active heterodiatomic motifs,more exposed nanoporous channels,and successive charge migration paths,SCSs cathode promises high accessibility of built-in zincophilic sites and rapid ion diffusion with low energy barriers(3.3Ωs-0.5).Consequently,the assembled Zn||SCSs capacitor harvests all-round improvement in Zn-ion storage metrics,including high energy density(166 Wh kg-1),high-rate performance(172 m Ah g^(-1)at 20 A g^(-1)),and long-lasting cycling lifespan(95.5%capacity retention after 500,000 cycles).An opposite chargecarrier storage mechanism is rationalized for SCSs cathode to maximize spatial capacitive charge storage,involving high-kinetics physical Zn^(2+)/CF_(3)SO_(3)-adsorption and chemical Zn^(2+)redox with carbonyl/pyridine groups.This work gives insights into H-bond-guided interfacial superassembly design of superstructural carbons toward advanced energy storage.
基金supported by the National Natural Science Foundation of China(Grant No.52573299)the Natural Science Foundation of Jiangxi province(No.20242BAB25223,20232BCJ23025,20232BCJ25040,20232BAB214024)the Special Funding Program for Graduate Student Innovation of Jiangxi Province(No.YC2024-S594).
文摘Transition metal selenides as sodium-ion hybrid capacitor(SIHC)anodes still suffer from amorphization difficulties and capacity degradation triggered by polyselenide dissolution.Herein,an atomistic amorphous strategy is proposed to construct adjacent Nb-Nb diatomic pairs with Se/O-coordination(Se4-Nb2-O2)in N-doped carbon-confined amorphous selenide clusters(a-Nb-Se/O@NC).Synergistic carbon confinement and hydrothermal oxygenation induce amorphization of Nb–Se bonds,eliminating crystalline rigidity while creating isotropic dual-ion transport channels and high-density active sites enriched with dangling bonds,thereby enhancing structural integrity and Na+storage capacity.The unique Se/O-coordinated Nb-Nb diatomic configuration establishes an electron-delocalized system,where the low electronegativity of Se counterbalances electron withdrawal from coordinated O at Nb centers.These strengthen d-p orbital hybridization,reduce Na+adsorption energy,and optimize charge transfer pathways and reaction kinetics in the amorphous clusters.Electrochemical tests reveal that the a-Nb-Se/O@NC anode delivers a high reversible capacity of 312.57 mAh g^(−1)and exceptional cyclic stability(103%capacity retention)after 5000 cycles at 10.0 A g^(−1).Assembled SIHCs achieve outstanding energy/power densities(207.1 Wh kg^(−1)/18966 W kg^(−1)),surpassing most amorphous and crystalline counterparts.This work provides methodological insights for the design of electrodes in high-power storage devices through atomic modulation and electronic optimization of amorphous selenides.
基金financially supported by the National Natural Science Foundation of China(No.22279122)Zhejiang Provincial Natural Science Foundation of China(No.LZ22B030004)the Foundation of State Key Laboratory of Coal Conversion(No.J22-23-909)。
文摘Hybrid Na-ion capacitors(NICs)have received considerable interests owing to their low-cost,high-safety,and rapidly charging energy-storage characteristics.The NICs are composed of a capacitor-type cathode and a battery-type anode.The major challenge for NICs is to search for suitable electrode materials to overcome the sluggish diffusion of Na^(+)in the anode.Herein,ultrafine vanadium sulfide is encapsulated in carbon fiber(V_(3)S_(4)@CNF)as a self-supported electrode by electrospinning and in situ sulfurization.The carbon cladding and one-dimensional(ID)nanofiber network-like structure could alleviate the volume expansion of V_(3)S_(4)during Na^(+)de-/intercalation process.Consequently,the V_(3)S_(4)@CNF anode exhibited a pseudocapacitive sodium storage in terms of large Na^(+)-storage capacity(476 mAh·g^(-1)at 0.1A·g^(-1)),high-rate capability(290 mAh·g^(-1)at 20.0 A·g^(-1))and excellent cycling stability(95%capacity retention for1500 cycles at 2.0 A·g^(-1))in Na half-cells.By employing V_(3)S_(4)@CNF as the anode and the activated carbon(AC)cathode,the as-assembled NICs could deliver a high energy density of 110 Wh·kg^(-1)at a power density of200 W·kg^(-1).Even at a high power of 10,000 W·kg^(-1),the specific energy is still up to 42 Wh·kg^(-1).
基金financially supported by the National Natural Science Foundation of China(52077207 and 51907193)the Key Research Program of Frontier Sciences,CAS(ZDBS-LY-JSC047)the Youth Innovation Promotion Association CAS(2020145)。
文摘Practical applications of diverse flexible wearable electronics require electrochemical energy storage(EES)devices with multiple configurations.Moreover,to fabricate flexible EES devices with high energy density and stability,organic integration from electrode design to device assembly is required.To address these challenges,a free-standing reduced graphene oxide(rGO)/carbon film with a unique sandwich structure has been designed via the assistance of vacuum-assistant filtration for lithium-ion capacitors(LICs).The graphene acts as not only a binder to construct a three-dimensional conductive network but also an active material to provide additional capacitive lithium storage sites,thus enabling fast ion/electron transport and improving the capacity.The designed rGO/hard carbon(rGO/HC)and rGO/activated carbon(rGO/AC)free-standing films exhibit enhanced specific capacities(513.7 mA h g^(-1)for rGO/HC and 102.8 mA h g^(-1)for rGO/AC)and excellent stability.Moreover,the integrated flexible quasi-solid-state rGO/AC//rGO/HC LIC devices possess a maximum energy density of 138.3 Wh kg^(-1),a high power density of 11 kW kg^(-1),and improved cycling performance(84.4%capacitance maintained after 10,000 cycles),superior to the AC//HC LIC(43.5%retention).Such a strategy enlightens the development of portable flexible LICs.
基金financially supported by the National Key R@D Program of China(Grants 2016YBF0100100 and 2016YFA0200200)National Natural Science Foundation of China(Grants 51872283,and 21805273)+8 种基金Liaoning BaiQianWan Talents Program,LiaoNing Revitalization Talents Program(Grant XLYC1807153)Natural Science Foundation of Liaoning Province(2020-MS-095)Joint Research Fund Liaoning-Shenyang National Laboratory for Materials Science(Grants 20180510038)DICP(DICP ZZBS201708,DICP ZZBS201802,and DICP I202032)DICP&QIBEBT(Grant No.DICP&QIBEBT UN201702)Dalian National Laboratory For Clean Energy(DNL),CAS,DNL Cooperation Fund,CAS(DNL180310,DNL180308,DNL201912,and DNL201915)the Fundamental Research Funds for the Central Universities of China(N180503012)the State Key Laboratory of Fine Chemicals(KF1911)the CAS Key Laboratory of Carbon Materials(KLCMKFJJ2004)。
文摘Aqueous zinc ion hybrid capacitors(ZIHCs)hold great potential for large-scale energy storage applications owing to their high safety and low cost,but suffer from low capacity and energy density.Herein,pyridinic nitrogen enriched porous carbon(nPC)was successfully synthesized via the growth,subsequent annealing and acid etching of bimetal organic frameworks for high capacity and safe ZIHCs with exceptional rate capability.Benefiting from the mesopores for easy ion diffusion,high electrical conductivity enabled by in-situ grown carbon nanotubes matrix and residual metal Co nanoparticles for fast electron transfer,sufficient micropores and high N content(8.9 at%)with dominated pyridinic N(54%)for enhanced zinc ion storage,the resulting nPC cathodes for ZIHCs achieved high capacities of 302 and137 m Ah g^(-1) at 1 and 18 A g^(-1),outperforming most reported carbon based cathodes.Theoretical results further disclosed that pyridinic N possessed larger binding energy of-4.99 eV to chemically coordinate with Zn2+than other N species.Moreover,quasi-solid-state ZIHCs with gelatin based gel electrolytes exhibited high energy density of 157.6 Wh kg^(-1) at 0.69 kW kg^(-1),high safety and mechanical flexibility to withstand mechanical deformation and drilling.This strategy of developing pyridinic nitrogen enriched porous carbon will pave a new avenue to construct safe ZIHCs with high energy densities.
基金the National Natural Science Foundation of China(No.50134020)
文摘Nanosized nickel oxide powders were prepared by thermal decomposition of the nickel citrate gel precursors. The thermal decomposition and powder materials derived from calcination of these gel precursors with various ratios of citric acid （CA） to nickel at different temperatures and times were characterized by thermal analysis （TG/DTA）, scanning electron microscopy （SEM）, x-ray diffraction （XRD）, and measurement of specific surface area （BET） with porosity analyses. The optimized processing conditions of calcination temperature 400℃ for 1 hour with the CA/Ni ratio of 1.2, were determined to produce the nanosized nickel oxide pow- ders with a high specific surface area of 181 m^2/g, nanometer particle sizes of 15-25 nm, micro-pore diameter distribution between 4-10 nm. The capacitance characteristics of the nanosized nickel oxide electrode in various concentrations of KOH solutions were studied by the cyclic voltammetry （CV） exhibiting both a double-layer capacitance and a faradaic pseudocapacitance. The nanosized nickel oxide electrode shows a high cyclic stability and is promising for high performance electrochemical capacitors.
文摘A new sol-gel process for the preparation of ultrafine nickel hydroxideelectrode materials was developed. The composite electrodes consisting of carbon nanotubes andNi(OH)_2 were developed by mixing the hydroxide and carbon nanotubes together in different massratios. In order to enhance energy density, a combined type pseudocapacitor/electric double layercapacitor was considered and its electrochemical properties were characterized by cyclic voltammetryand dc charge/discharge test. The combined capacitor shows excellent capacitor behavior with anoperating voltage up to 1.6 V in KOH aqueous electrolyte. Stable charge/discharge behaviors wereobserved with much higher specific capacitance values of 24 F/g compared with that of EDLC (12 F/g)by introducing 60 percent Ni(0H)_2 in the anode material. By using the modified anode of aNi(OH)_2/carbon nanotubes composite electrode, the specific capacitance of the cell was lesssensitive to discharge current density compared with that of the capacitor employing pure nickelhydroxide as anode. The combined capacitor in this study exhibits high energy density and stablepower characteristics.
基金We are grateful to National Natural Science Foundation of China(Grant No.22375056,52272163)the Key R&D Program of Hebei(Grant No.216Z1201G)+1 种基金Natural Science Foundation of Hebei Province(Grant No.E2022208066,B2021208014)Key R&D Program of Hebei Technological Innovation Center of Chiral Medicine(Grant No.ZXJJ20220105).
文摘Free-standing covalent organic framework(COFs)nanofilms exhibit a remarkable ability to rapidly intercalate/de-intercalate Li^(+) in lithium-ion batteries,while simultaneously exposing affluent active sites in supercapacitors.The development of these nanofilms offers a promising solution to address the persistent challenge of imbalanced charge storage kinetics between battery-type anode and capacitor-type cathode in lithium-ion capacitors(LICs).Herein,for the first time,custom-made COFBTMB-TP and COFTAPB-BPY nanofilms are synthesized as the anode and cathode,respectively,for an all-COF nanofilm-structured LIC.The COFBTMB-TP nanofilm with strong electronegative–CF3 groups enables tuning the partial electron cloud density for Li^(+) migration to ensure the rapid anode kinetic process.The thickness-regulated cathodic COFTAPB-BPY nanofilm can fit the anodic COF nanofilm in the capacity.Due to the aligned 1D channel,2D aromatic skeleton and accessible active sites of COF nanofilms,the whole COFTAPB-BPY//COFBTMB-TP LIC demonstrates a high energy density of 318 mWh cm^(−3) at a high-power density of 6 W cm^(−3),excellent rate capability,good cycle stability with the capacity retention rate of 77%after 5000-cycle.The COFTAPB-BPY//COFBTMB-TP LIC represents a new benchmark for currently reported film-type LICs and even film-type supercapacitors.After being comprehensively explored via ex situ XPS,7Li solid-state NMR analyses,and DFT calculation,it is found that the COFBTMB-TP nanofilm facilitates the reversible conversion of semi-ionic to ionic C–F bonds during lithium storage.COFBTMB-TP exhibits a strong interaction with Li^(+) due to the C–F,C=O,and C–N bonds,facilitating Li^(+) desolation and absorption from the electrolyte.This work addresses the challenge of imbalanced charge storage kinetics and capacity between the anode and cathode and also pave the way for future miniaturized and wearable LIC devices.
文摘Cobalt selenide(CoSe_(2))has garnered considerable attention as a prospective anode candidate for advanced lithium-ion storage,prompting comprehensive investigations.However,CoSe_(2)-based anodes usually suffer from significant volume variation upon lithiation leading to unsatisfactory cycling stability.Herein,a versatile synthesis route is proposed for the in-situ fabrication of CoSe2nanoparticles embedded in N-dope carbon skeleton(CoSe_(2)@NC)through annealing treatment and selenization of a metal–organic framework-derived(MOF)precursor.The N-doped carbon derived from the MOF serves not only as an excellent conductive substrate but also as a confined reactor,effectively inhibiting the structural instability and alleviating the inevitable volume change of CoSe_(2).Owing to their unique nanostructure,the as-prepared CoSe_(2)@NC exhibits a high capacity of 745.9mAh·g^(-1)at 0.1 A·g^(-1),while maintaining excellent rate capability and an impressive lifespan.Furthermore,the assembled lithium-ion capacitor(LIC)based on CoSe_(2)@NC demonstrates an energy density of 130Wh·kg^(-1),a power density of 24.6 kW·kg^(-1),and remarkable capacity retention of 90.8%after 8000 cycles.These results highlight the great potential of CoSe_(2)@NC for practical applications.
基金supported by the National Natural Science Foundation of China(No.51877146)。
文摘Nickel–cobalt tellurides are deemed as promising electrode materials for energy storage devices due to their superior conductivity and theoretical specific capacitance.Here,NiCoTe_(2)was successfully fabricated on carbon cloth by facile electrodeposition and hydrothermal synthesis,which can directly serve as a binderless electrode.The NiCoTe_(2)with interconnected nanosheet arrays on a conductive carbon substrate showed a high specific capacitance(924 F/g at 1 A/g)and robust longterm cycling stability(89.6%retention after 5000 cycles).In addition,the assembled NiCoTe_(2)//activiated carbon hybrid supercapacitor achieved a high energy and power density with a short charging time(42.26 Wh/kg at a power density of 760.96 W/kg).This work provides a novel idea to produce bimetallic nickel–cobalt telluride nanosheet array electrodes for high-performance hybrid supercapacitors.
文摘There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of traditional rechargeable batteries with the superior power density and long life of supercapacitors(SCs).Nevertheless,the development of LICs is still hampered by limited kinetic processes and capacity mismatch between the cathode and anode.Metal-organic frameworks(MOFs)and their derivatives have received significant attention because of their extensive specific surface area,different pore structures and topologies,and customizable functional sites,making them compelling candidate materials for achieving high-performance LICs.MOF-derived carbons,known for their exceptional electronic conductivity and large surface area,provide improved charge storage and rapid ion transport.MOF-derived transition metal oxides contribute to high specific capacities and improved electrochemical stability.Additionally,MOF-derived metal compounds/carbons provide combined effects that increase both the capacitive and Faradaic reactions,leading to a superior overall performance.The review begins with an overview of the fundamental principles of LICs,followed by an exploration of synthesis strategies and ligand selection for MOF-based composite materials.It then analyzes the advantages of original MOFs and their derived materials,such as carbon materials and metal compounds,in enhancing LIC performance.Finally,the review discusses the major challenges faced by MOFs and their derivatives in LIC applications and offers future research directions and recommendations.
基金Supported by the Doctoral Program Foundation of Institutions of Higher Education of China (No.20120111120008)State Key Lab of ASIC & System(Fudan University) (No. 11KF001)Special Fund for Doctoral Program (Hefei University of Technology) (No.2011HGBZ0953)
文摘A correlation-based digital background calibration algorithm for pipelined Analog-to- Digital Converters (ADCs) is presented in this paper. The merit of the calibration algorithm is that the main errors information, which include the capacitor mismatches and residue amplifier distortion, are extracted integrally. A modified 1st pipelined stage is adopted to solve the signal overflow caused by the Pseudo-random Noise (PN) sequences. Behavioral simulation results verify the effectiveness of the algorithm. It improves the Signal-to-Noise-plus-Distortion Ratio (SNDR) and Spurious-Free-Dynamic-Range (SFDR) of the pipelined ADC from 41.8 dB to 78.3 dB and 55.6 dB to 98.6 dB, respectively, which is comparable to the prior arts.
文摘The large variability in wind output power can adversely impact local loads that are sensitive to poor power quality. To mitigate large swings in power, the wind turbine output power can be conditioned by using a small energy buffer. A power conditioner is developed to smooth the wind power output by utilizing the energy of an electrochemical capacitor, or ultracapacitor. The conditioner is based on a single phase voltage source inverter connected between the grid inter-connection point and the ultracapacitor. The VSI shunt inverter injects or absorbs active power from the line to smooth the wind power output by utilizing the short term storage capabilities of the ultracapacitor. The ultracapacitor is connected to the DC link through a bidirectional DC-DC converter. The bidirectional DC-DC converter and VSI are constructed and field tested on a Skystream 3.7 wind turbine installed at the Missouri University of Science & Technology.
基金This work was financially supported by the National Natural Science Foundation(51972235)the Natural Science Foundation of Shanghai(17ZR1447800)+1 种基金Jiangsu Key R&D Plan(BE2018006-4)the Program for Professor of Special Appointment(Eastern Scholar)at the Shanghai Institutions of Higher Learning and the Fundamental Research Funds for the Central Universities.
文摘Potassium-ion capacitors(KICs)are promising for sustainable and eco-friendly energy storage technologies,yet their slow reaction kinetics and poor cyclability induced by large K-ion size are a major obstacle toward practical applications.Herein,by employing black phosphorus nanosheets(BPNSs)as a typical high-capacity anode material,we report that BPNS anodes armored with an ultrathin oriented-grown metal–organic-framework(MOF)interphase layer(BPNS@MOF)exhibit regulated potassium storage behavior for highperformance KICs.The MOF interphase layers as protective layer with ordered pores and high chemical/mechanical stability facilitate K ion diffusion and accommodate the volume change of electrode,beneficial for improved reaction kinetics and enhanced cyclability,as evidenced by substantial characterizations,kinetics analysis and DFT calculations.Consequently,the BPNS@MOF electrode as KIC anodes exhibits outstanding cycle performance outperforming most of the reported state-of-art KICs so far.
基金supported by the National Key Research and Development Program of China(Grant No.2016YFA0301801)the National Natural Science Foundation of China(Grant Nos.11474154 and 61521001)the Priority Academic Development Program of Jiangsu Higher Education Institutions and Dengfeng Project B of Nanjing University,China
文摘Using the diluted S1813 UV photoresist as a sacrificial layer, we successfully fabricate a superconducting suspended parallel-plate capacitor, in which the top layer of aluminum film acts as a membrane mechanical resonator. Together with a superconducting octagonal spiral inductor, this parallel-plate capacitor constitutes a superconducting microwave resonator. At m K temperature, the transmission characteristic and spectrum of the microwave resonator are measured.Sideband frequencies caused by the vibration of the membrane mechanical resonator are clearly demonstrated. By downconverting with a mixer, the dependence of fundamental frequency and its harmonics on the input microwave power are clearly demonstrated, which is consistent with the numerical simulation.
