Supercapacitors,comprising electrical double-layer capacitors(EDLCs)and pseudocapa-citors,are widely acknowledged as high-power energy storage devices.However,their local structures and fundamental mechanisms remain p...Supercapacitors,comprising electrical double-layer capacitors(EDLCs)and pseudocapa-citors,are widely acknowledged as high-power energy storage devices.However,their local structures and fundamental mechanisms remain poorly understood,and suitable experimental techniques for investigation are also lacking.Recently,nuclear magnetic resonance(NMR)has emerged as a powerful tool for addressing these fundamental issues with high local sensitivity and non-invasiveness.In this paper,we first review the limi-tations of existing characterization methods and highlight the advantages of NMR in investigating mechanisms of supercapacitors.Subsequently,we introduce the basic prin-ciple of ring current effect,NMR-active nuclei,and various NMR techniques employed in exploring energy storage mechanisms including cross polarization(CP)magic angle spinning(MAS)NMR,multiple-quantum(MQ)MAS,two-dimensional exchange spec-troscopy(2D-EXSY)NMR,magnetic resonance imaging(MRI)and pulsed-field gradient(PFG)NMR.Based on this,recent progress in investigating energy storage mechanisms in EDLCs and pseudocapacitors through various NMR techniques is discussed.Finally,an outlook on future directions for NMR research in supercapacitors is offered.展开更多
The global rise in energy demand, particularly in remote and sparsely populated regions, necessitates innovative and cost-effective electrical distribution solutions. Traditional Rural Electrification (RE) methods, li...The global rise in energy demand, particularly in remote and sparsely populated regions, necessitates innovative and cost-effective electrical distribution solutions. Traditional Rural Electrification (RE) methods, like Conventional Rural Electrification (CRE), have proven economically unfeasible in such areas due to high infrastructure costs and low electricity demand. Consequently, Unconventional Rural Electrification (URE) technologies, such as Capacitor Coupled Substations (CCS), are gaining attention as viable alternatives. This study presents the design and simulation of an 80 kW CCS system, which taps power directly from a 132 kV transmission line to supply low-voltage consumers. The critical components of the CCS, the capacitors are calculated, then a MATLAB/Simulink model with the attained results is executed. Mathematical representation and state-space representation for maintaining the desired tapped voltage area also developed. The research further explores the feasibility and operational performance of this CCS configuration, aiming to address the challenges of rural electrification by offering a sustainable and scalable solution. The results show that the desired value of the tapped voltage can be achieved at any level of High Voltage (HV) with the selection of capacitors that are correctly rated. With an adequately designed control strategy, the research also shows that tapped voltage can be attained under both steady-state and dynamic loads. By leveraging CCS technology, the study demonstrates the potential for delivering reliable electricity to underserved areas, highlighting the system’s practicality and effectiveness in overcoming the limitations of conventional distribution methods.展开更多
Metal-insulator-metal aluminium electrolytic capacitors(MIM-AECs)combine high capacity-density and high breakdown field strength of solid AECs with high-frequency responsibility,wide workingtemperature window and wate...Metal-insulator-metal aluminium electrolytic capacitors(MIM-AECs)combine high capacity-density and high breakdown field strength of solid AECs with high-frequency responsibility,wide workingtemperature window and waterproof properties of MIM nanocapacitors.However,interfacial atomic diffusion poses a major obstacle,preventing the high-voltage MIM-AECs exploitation and thereby hampering their potential and advantages in high-power and high-energy-density applications.Here,an innovative high-voltage MIM-AECs were fabricated.The AlPO_(4)buffer layer is formed on AlO(OH)/AAO/Al surface by using H_(3)PO_(4)treatment,then a stable van der Waals(vdW)SnO_(2)/AlPO_(4)/AAO/Al multilayer was constructed via atomic layer deposition(ALD)technology.Due to higher diffusion barrier and lower carrier migration of SnO_(2)/AlPO_(4)/AAO interfaces,Sn atom diffusion is inhibited and carrier acceleration by electric field is weakened,guaranteeing high breakdown field strength of dielectric AAO and avoiding local breakdown risks.Through partial etching to hydrated AlO(OH)by H_(3)PO_(4)treatment,the tunnel was further opened up to facilitate subsequent ALD-SnO_(2)entry,thus obtaining a high SnO_(2)coverage.The SnO_(2)/AlPO_(4)/AAO/Al capacitors show a comprehensive performance in high-voltage(260 V),hightemperature(335℃),high-humidity(100%RH)and high-frequency response(100 k Hz),outperforming commercial solid-state AECs,and high-energy density(8.6μWh/cm^(2)),markedly exceeding previously reported MIM capacitors.The work lays the foundation for next-generation capacitors with highvoltage,high-frequency,high-temperature and high-humidity resistance.展开更多
In the context of rapid economic development,the pursuit of sustainable energy solutions has become a major challenge.Lithium-ion capacitors(LICs),which integrate the high energy density of lithium-ion batteries with ...In the context of rapid economic development,the pursuit of sustainable energy solutions has become a major challenge.Lithium-ion capacitors(LICs),which integrate the high energy density of lithium-ion batteries with the high power density of supercapacitors,have emerged as promising candidates.However,challenges such as poor capacity matching and limited energy density still hinder their practical application.Carbon nanofibers(CNFs),with their high specific surface area,excellent electrical conductivity,mechanical flexibility,and strong compatibility with active materials,are regarded as ideal electrode frameworks for LICs.This review summarizes key strategies to improve the electrochemical performance of CNF-based LICs,including structural engineering,heteroatom doping,and hybridization with transition metal oxides.The underlying mechanisms of each approach are discussed in detail,with a focus on their roles in improving capacitance,energy density,and cycling stability.This review aims to provide insights into material design and guide future research toward high-performance LICs for next-generation energy storage applications.展开更多
The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively ...The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively applying mono-capacitor positioning, multiple positioning and reconfiguration processes using GA-based algorithms implemented in a Matlab environment. From the diagnostic study of this network, it was observed that a minimum voltage of 0.90 pu induces a voltage deviation of 5.26%, followed by active and reactive losses of 425.08 kW and 435.09 kVAR, respectively. Single placement with the NSGAII resulted in the placement of a 3000 kVAR capacitor at node 128, which proved to be the invariably neuralgic point. Multiple placements resulted in a 21.55% reduction in losses and a 0.74% regression in voltage profile performance. After topology optimization, the loss profile improved by 65.08% and the voltage profile improved by 1.05%. Genetic algorithms are efficient and effective tools for improving the performance of distribution networks, whose degradation is often dynamic due to the natural variability of loads.展开更多
A pseudocapacitance dominated anode material assembled from Li_(3)VO_(4)nanocrystals encapsulated in the interlayers of N-doped graphene has been developed via a facile 2D nanospace confined strategy for lithium ion c...A pseudocapacitance dominated anode material assembled from Li_(3)VO_(4)nanocrystals encapsulated in the interlayers of N-doped graphene has been developed via a facile 2D nanospace confined strategy for lithium ion capacitors(LICs).In this contribution,the N-doped graphene synthesized by a faicle solid state reaction using C_(3)N_(4)nanosheets as template and glucose as carbon source provides sufficient 2D nanospace for the confined and homogeneous growth of Li_(3)VO_(4)at the nanoscale,and simultaneously efficiently anchors each nanobuilding block inside the interlayers,thus realizing the utilizaiton of full potential of active components.The so-formed 3D hybrids not only ensure intimate electronic coupling between active materials and N-doped graphene,but also realize robust structure integrity.Owing to these unique advantages,the resulting hybrids show pseudocapacitance dominated lithium storage behaviors with capacitive contributions of over 90%at both low and high current rates.The LVO@C@NG delivers reversible capacities of 206 mAh/g at 10 A/g,capacity retention of 92.7%after 1000 cycles at 2 A/g,and a high energy density of 113.6 Wh/kg at 231.8 W/kg for LICs.展开更多
Reconfiguration,as well as optimal utilization of distributed generation sources and capacitor banks,are highly effective methods for reducing losses and improving the voltage profile,or in other words,the power quali...Reconfiguration,as well as optimal utilization of distributed generation sources and capacitor banks,are highly effective methods for reducing losses and improving the voltage profile,or in other words,the power quality in the power distribution system.Researchers have considered the use of distributed generation resources in recent years.There are numerous advantages to utilizing these resources,the most significant of which are the reduction of network losses and enhancement of voltage stability.Non-dominated Sorting Genetic Algorithm II(NSGA-II),Multi-Objective Particle Swarm Optimization(MOPSO),and Intersect Mutation Differential Evolution(IMDE)algorithms are used in this paper to perform optimal reconfiguration,simultaneous location,and capacity determination of distributed generation resources and capacitor banks.Three scenarios were used to replicate the studies.The reconfiguration of the switches,as well as the location and determination of the capacitor bank’s optimal capacity,were investigated in this scenario.However,in the third scenario,reconfiguration,and determining the location and capacity of the Distributed Generation(DG)resources and capacitor banks have been carried out simultaneously.Finally,the simulation results of these three algorithms are compared.The results indicate that the proposed NSGAII algorithm outperformed the other two multi-objective algorithms and was capable of maintaining smaller objective functions in all scenarios.Specifically,the energy losses were reduced from 211 to 51.35 kW(a 75.66%reduction),119.13 kW(a 43.54%reduction),and 23.13 kW(an 89.04%reduction),while the voltage stability index(VSI)decreased from 6.96 to 2.105,1.239,and 1.257,respectively,demonstrating significant improvement in the voltage profile.展开更多
Zinc-ion hybrid capacitors (ZIHCs) have received increasing attention as energy storage devices owing to their low cost,high safety,and environmental friendliness.However,their progress has been hampered by low energy...Zinc-ion hybrid capacitors (ZIHCs) have received increasing attention as energy storage devices owing to their low cost,high safety,and environmental friendliness.However,their progress has been hampered by low energy and power density,as well as unsatisfactory long-cycle stability,mainly due to the lack of suitable electrode materials.In this context,we have developed manganese single atoms implanted in nitrogen-doped porous carbon nanosheets (MnSAs/NCNs) using a metal salt template method as cathodes for ZIHCs.The metal salt serves a dual purpose in the synthesis process:It facilitates the uniform dispersion of Mn atoms within the carbon matrix and acts as an activating agent to create the porous structure.When applied in ZIHCs,the MnSAs/NCNs electrode demonstrates exceptional performance,including a high capacity of 203 m Ah g^(-1),an energy density of 138 Wh kg^(-1)at 68 W kg^(-1),and excellent cycle stability with 91%retention over 10,000 cycles.Theoretical calculations indicate that the introduced Mn atoms modulate the local charge distribution of carbon materials,thereby improving the electrochemical property.This work demonstrates the significant potential of carbon materials with metal atoms in zinc-ion hybrid capacitors,not only in enhancing electrochemical performance but also in providing new insights and methods for developing high-performance energy storage devices.展开更多
Oxygen-rich porous carbons are promising candidates for the carbon-based cathodes of zinc ion hybrid capacitors(ZIHCs).Potassium activation is a traditional and effective way to prepare oxygen-rich porous carbons.Effi...Oxygen-rich porous carbons are promising candidates for the carbon-based cathodes of zinc ion hybrid capacitors(ZIHCs).Potassium activation is a traditional and effective way to prepare oxygen-rich porous carbons.Efficient potassium activation is the key to develop high-performance oxygen-rich porous carbon cathodes.Herein,the alkali lignin,extracted from eucalyptus wood by geopolymer-assisted low-alkali pretreatment,is used to prepare oxygen-rich lignin-derived porous carbons(OLPCs)through KOH activation and K_(2)CO_(3)activation at 700-900℃.KOH activation constructs a hierarchical micro-mesoporous structure,while K_(2)CO_(3)activation constructs a microporous structure.Furthermore,K_(2)CO_(3)activation could more efficiently construct active oxygen(C=O)species than KOH activation.The OLPCs prepared by KOH/K_(2)CO_(3)activations at 800℃show the highest microporosity(78.4/87.7%)and C=O content(5.3/8.0 at.%).Due to that C=O and micropore adsorb zinc ions,the OLPCs prepared by K_(2)CO_(3)activation at 800℃with higher C=O content and microporosity deliver superior capacitive performance(256 F g^(-1)at 0.1 A g^(-1))than that by KOH activation at 800℃(224 F g^(-1)at 0.1 A g^(-1)),and excellent cycling stability.This work provides a new insight into the sustainable preparation of oxygenrich porous carbon cathodes through efficient potassium activation for ZIHCs.展开更多
Submodule capacitor aging poses significant challenges to the safe operation of modular multilevel converter(MMC)systems.Traditional detection methods rely predominantly on offline tests,lacking real-time evaluation c...Submodule capacitor aging poses significant challenges to the safe operation of modular multilevel converter(MMC)systems.Traditional detection methods rely predominantly on offline tests,lacking real-time evaluation capabilities.Moreover,existing online approaches require additional sampling channels,thereby increasing system complexity and costs.To address these issues,this paper proposes an online evaluation method for submodule capacitor aging based on CapAgingNet.Initially,an MMC system simulation platform is developed to examine the effects of submodule capacitor aging on system operational characteristics and to create a dataset of submodule capacitor switching states.Subsequently,the CapAgingNet model is introduced,incorporating key technical modules to enhance performance:the Deep Stem module,which extracts larger receptive fields through multiple convolution layers and mitigates the impact of data sparsity in capacitor aging on feature extraction;the efficient channel attention(ECA)module,utilizing onedimensional convolution for dynamic weighting to adjust the importance of each channel,thereby enhancing the ability of the model to process high-dimensional features in capacitor aging data;and the multiscale feature fusion(MSF)module,which integrates capacitor aging information across different scales by combining fine-grained and coarse-grained features,thus improving the capacity of the model to capture high-frequency variation characteristics.The experimental results reveal that the CapAgingNet model achieves a TOP-1 accuracy of 95.32%and a macro-averaged F1 score of 95.49%on the test set,thereby providing effective technical support for online monitoring of submodule capacitor aging.展开更多
The rise of Zn-ion hybrid capacitor(ZHC)has imposed high requirements on carbon cathodes,including reasonable configuration,high specific surface area,multiscale pores,and abundant defects.To achieve this objective,a ...The rise of Zn-ion hybrid capacitor(ZHC)has imposed high requirements on carbon cathodes,including reasonable configuration,high specific surface area,multiscale pores,and abundant defects.To achieve this objective,a template-oriented strategy coupled with multi-heteroatom modification is proposed to precisely synthesize a three-dimensional boron/nitrogen-rich carbon nanoflake-interconnected micro/nano superstructure,referred to as BNPC.The hierarchically porous framework of BNPC shares short channels for fast Zn2+transport,increased adsorption-site accessibility,and structural robustness.Additionally,the boron/nitrogen incorporation effect significantly augments Zn2+adsorption capability and more distinctive pseudocapacitive nature,notably enhancing Zn-ion storage and transmission kinetics by performing the dual-storage mechanism of the electric double-layer capacitance and Faradaic redox process in BNPC cathode.These merits contribute to a high capacity(143.7 mAh g^(-1)at 0.2 A g^(-1))and excellent rate capability(84.5 mAh g^(-1)at 30 A g^(-1))of BNPC-based aqueous ZHC,and the ZHC still shows an ultrahigh capacity of 108.5 mAh g^(-1)even under a high BNPC mass loading of 12 mg cm^(-2).More critically,the BNPC-based flexible device also sustains notable cyclability over 30,000 cycles and low-rate self-discharge of 2.13 mV h-1 along with a preeminent energy output of 117.15 Wh kg^(-1)at a power density of 163.15Wkg^(-1),favoring a creditable applicability in modern electronics.In/ex-situ analysis and theoretical calculations elaborately elucidate the enhanced charge storage mechanism in depth.The findings offer a promising platform for the development of advanced carbon cathodes and corresponding electrochemical devices.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
Along with the surging demand for energy storage devices,the cost and availability of the materials remain dominant factors in slowing down their industrial application.The repurposing of waste asphalt into high-perfo...Along with the surging demand for energy storage devices,the cost and availability of the materials remain dominant factors in slowing down their industrial application.The repurposing of waste asphalt into high-performance electrode materials is of significant interest,as it holds the potential to circumvent energy and environmental issues.Here,we report the controllable synthesis of asphalt-derived mesoporous carbon as an active material for electrocatalytic hydrogen gas capacitor(EHGC).The hierarchically porous carbon(HPC)with a high surface area of 1943.4 m^(2)·g^(-1)can operate in pH universal aqueous electrolytes in EHGC.It displays a specific energy and power density of 57 Wh·kg^(-1)and 554 W·kg^(-1)in neutral electrolyte as well as 52 Wh·kg^(-1)and 657 W·kg^(-1)in acidic electrolyte.Additionally,the charge storage mechanism of HPC-EHGC is studied with the help of Raman spectroscopy and X-ray photoelectron spectroscopy.Furthermore,the assembled HPC-EHGC device displays a discharge capacitance of 170 F·g^(-1)with an excellent capacitance retention rate of 100%up to 20000 cycles at 10 A·g^(-1)in acidic electrolyte.This work introduces a novel approach to converting waste asphalt into high-performance carbon for EHGC,achieving superior performance over commercial materials.By simultaneously addressing environmental waste issues and advancing energy storage technology,this study makes a significant contribution to sustainable materials science and next-generation battery development.展开更多
Sodium-ion hybrid capacitors(SICs),which combine the high energy density of batteries with the high power density and long cycle life of capacitors,are considered promising next-generation energy storage devices.Ensur...Sodium-ion hybrid capacitors(SICs),which combine the high energy density of batteries with the high power density and long cycle life of capacitors,are considered promising next-generation energy storage devices.Ensuring the performance of SICs in low-temperature environments is crucial for applications in high-altitude cold regions,where the desolvation process of Na+and the transport process in the solid electrolyte interphase(SEI)are determinant.In this paper,we proposed a multi-ether modulation strategy to construct a solvation sheath with multi-ether participation by modulating the coordination of Na+and solvents.This unique solvation sheath not only reduces the desolvation energy barrier of Na+,but more importantly forms a Na_(2)O-rich inorganic SEI and enhances the ionic dynamics of Na+.Benefiting from the excellent solvation structure design,SICs prepared with this electrolyte can achieve energy density of up to 178 Wh·kg^(-1) and ultra-high power density of 42390 W·kg^(-1) at room temperature.Notably,this SIC delivers record-high energy densities of 149 Wh·kg^(-1) and 119 Wh·kg^(-1) as well as power densities of up to 25200 W·kg^(-1) and 24591 W·kg^(-1) at−20℃ and−40℃,respectively.This work provides new ideas for the development of high-performance SICs for low-temperature operating environments.展开更多
The advancement of aqueous magnesium ion energy storage devices encounters limitations due to the substantial hydration radius of magnesium ions(Mg^(2+))and their strong electrostatic interaction with the primary mate...The advancement of aqueous magnesium ion energy storage devices encounters limitations due to the substantial hydration radius of magnesium ions(Mg^(2+))and their strong electrostatic interaction with the primary material.Consequently,this study successfully developed a MnS/MnO heterostructure through a straightforward hydrothermal and annealing method,marking its initial application in aqueous magnesium ion capacitors(AMICs).The fabricated MnS/MnO heterostructure,characterized by S defects,also generates Mn defects via in-situ initiation of early electrochemical processes.This unique dual ion defects MnS/MnO heterostructure(DID-MnS/MnO)enables the transformation of MnS and MnO,initially not highly active electrochemically for Mg^(2+),into cathode materials exhibiting high electrochemical activity and superior performance.Moreover,DID-MnS/MnO enhances conductivity,improves the kinetics of surface redox reactions,and increases the diffusion rate of Mg^(2+).Furthermore,this study introduces a dual energy storage mechanism for DID-MnS/MnO,which,in conjunction with dual ion defects,offers additional active sites for Mg^(2+)insertion/deinsertion in the host material,mitigating volume expansion and structural degradation during repeated charge-discharge cycles,thereby significantly enhancing cycling reversibility.As anticipated,using a three-electrode system,the developed DID-MnS/MnO demonstrated a discharge specific capacity of 237.9 mAh/g at a current density of 0.1 A/g.Remarkably,the constructed AMIC maintained a capacity retention rate of 94.3%after 10000 cycles at a current density of 1.0 A/g,with a specific capacitance of 165.7 F/g.Hence,DID-MnS/MnO offers insightful perspectives for designing alternative clean energy sources and is expected to contribute significantly to the advancement of the clean energy sector.展开更多
Metal–insulator–semiconductor(MOS) capacitor is a key structure for high performance MOS field transistors(MOSFETs), requiring low leakage current, high breakdown voltage, and low interface states. In this paper, β...Metal–insulator–semiconductor(MOS) capacitor is a key structure for high performance MOS field transistors(MOSFETs), requiring low leakage current, high breakdown voltage, and low interface states. In this paper, β-Ga_(2)O_(3) MOS capacitors were fabricated with ALD deposited Al_(2)O_(3) using H_(2)O or ozone(O_(3)) as precursors. Compared with the Al_(2)O_(3) gate dielectric with H_(2)O as ALD precursor, the leakage current for the O_(3) precursor case is decreased by two orders of magnitude, while it keeps the same level at the fixed charges, interface state density, and border traps. The SIMS tests show that Al_(2)O_(3) with O_(3) as precursor contains more carbon impurities. The current transport mechanism analysis suggests that the C–H complex in Al_(2)O_(3) with O_(3) precursor serves as deep energy trap to reduce the leakage current. These results indicate that the Al_(2)O_(3)/β-Ga_(2)O_(3)MOS capacitor using the O_(3) precursor has a low leakage current and holds potential for application in β-Ga_(2)O_(3) MOSFETs.展开更多
Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical b...Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical behaviors,yet has not been unraveled.Here we propose an NH_(4)^(+)-modulated cationic solvation strategy to optimize cathodic spatial charge distribution and achieve dynamic Zn^(2+)/NH_(4)^(+)co-storage for boosting Zinc hybrid capacitors.Owing to the hierarchical cationic solvated structure in hybrid Zn(CF_(3)SO_(3))_(2)–NH_4CF_(3)SO_(3)electrolyte,high-reactive Zn^(2+)and small-hydrate-sized NH_4(H_(2)O))(4)^(+)induce cathodic interfacial Helmholtz plane reconfiguration,thus effectively enhancing the spatial charge density to activate 20%capacity enhancement.Furthermore,cathodic interfacial adsorbed hydrated NH_(4)^(+)ions afford high-kinetics and ultrastable C···H(NH_(4)^(+))charge storage process due to a much lower desolvation energy barrier compared with heavy and rigid Zn(H_(2)O)_6^(2+)(5.81 vs.14.90 eV).Consequently,physical uptake and multielectron redox of Zn^(2+)/NH_(4)^(+)in carbon cathode enable the zinc capacitor to deliver high capacity(240 mAh g^(-1)at 0.5 A g^(-1)),large-current tolerance(130 mAh g^(-1)at 50 A g^(-1))and ultralong lifespan(400,000cycles).This study gives new insights into the design of cathode–electrolyte interfaces toward advanced zinc-based energy storage.展开更多
Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because th...Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected.展开更多
The exploration of advanced materials through rational structure/phase design is the key to develop highperformance lithium-ion capacitors(LICs).However,high complexity of material preparation and difficulty in quanti...The exploration of advanced materials through rational structure/phase design is the key to develop highperformance lithium-ion capacitors(LICs).However,high complexity of material preparation and difficulty in quantity production largely hinder the further development.Herein,Cu_(5)FeS_(4-x)/C(CFS@C)heterojunction with rich sulfur vacancies has successfully achieved from natural bornite,presenting low costeffective and bulk-production prospect.Density functional theory(DFT)calculations indicate that rich vacancies in bulk phase can decrease band gap of bornite and thus improve its intrinsic electron conductivity,as well as the heterojunction spontaneously evokes a built-in electric field between its interfacial region,largely reducing the migration barrier from 1.27 e V to 0.75 e V.Benefited from these merits,the CFS@C electrodes deliver outperformed lithium storage performance,e.g.,high reversible capacity(822.4m Ah/g at 0.1 A/g),excellent cycling stability(up to 820 cycles at 2 A/g and 540 cycles at 5 A/g with respective capacity retention of over or nearly 100%).With CFS@C as anode and porous carbon nanosheets(PCS)as cathode,the assembled CFS@C//PCS LIC full cells exhibit high energy/power density characteristics of 139.2 Wh/kg at 2500 W/kg.This work is expected to offer significant insights into structure modifications/devising toward natural minerals for advanced energy-storage systems.展开更多
Cascaded H-bridge inverter(CHBI) with supercapacitors(SCs) and dc-dc stage shows significant promise for medium to high voltage energy storage applications. This paper investigates the voltage balance of capacitors wi...Cascaded H-bridge inverter(CHBI) with supercapacitors(SCs) and dc-dc stage shows significant promise for medium to high voltage energy storage applications. This paper investigates the voltage balance of capacitors within the CHBI, including both the dc-link capacitors and SCs. Balance control over the dc-link capacitor voltages is realized by the dcdc stage in each submodule(SM), while a hybrid modulation strategy(HMS) is implemented in the H-bridge to balance the SC voltages among the SMs. Meanwhile, the dc-link voltage fluctuations are analyzed under the HMS. A virtual voltage variable is introduced to coordinate the balancing of dc-link capacitor voltages and SC voltages. Compared to the balancing method that solely considers the SC voltages, the presented method reduces the dc-link voltage fluctuations without affecting the voltage balance of SCs. Finally, both simulation and experimental results verify the effectiveness of the presented method.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.22075064)National Key Laboratory Projects(No.SYSKT20230056).
文摘Supercapacitors,comprising electrical double-layer capacitors(EDLCs)and pseudocapa-citors,are widely acknowledged as high-power energy storage devices.However,their local structures and fundamental mechanisms remain poorly understood,and suitable experimental techniques for investigation are also lacking.Recently,nuclear magnetic resonance(NMR)has emerged as a powerful tool for addressing these fundamental issues with high local sensitivity and non-invasiveness.In this paper,we first review the limi-tations of existing characterization methods and highlight the advantages of NMR in investigating mechanisms of supercapacitors.Subsequently,we introduce the basic prin-ciple of ring current effect,NMR-active nuclei,and various NMR techniques employed in exploring energy storage mechanisms including cross polarization(CP)magic angle spinning(MAS)NMR,multiple-quantum(MQ)MAS,two-dimensional exchange spec-troscopy(2D-EXSY)NMR,magnetic resonance imaging(MRI)and pulsed-field gradient(PFG)NMR.Based on this,recent progress in investigating energy storage mechanisms in EDLCs and pseudocapacitors through various NMR techniques is discussed.Finally,an outlook on future directions for NMR research in supercapacitors is offered.
文摘The global rise in energy demand, particularly in remote and sparsely populated regions, necessitates innovative and cost-effective electrical distribution solutions. Traditional Rural Electrification (RE) methods, like Conventional Rural Electrification (CRE), have proven economically unfeasible in such areas due to high infrastructure costs and low electricity demand. Consequently, Unconventional Rural Electrification (URE) technologies, such as Capacitor Coupled Substations (CCS), are gaining attention as viable alternatives. This study presents the design and simulation of an 80 kW CCS system, which taps power directly from a 132 kV transmission line to supply low-voltage consumers. The critical components of the CCS, the capacitors are calculated, then a MATLAB/Simulink model with the attained results is executed. Mathematical representation and state-space representation for maintaining the desired tapped voltage area also developed. The research further explores the feasibility and operational performance of this CCS configuration, aiming to address the challenges of rural electrification by offering a sustainable and scalable solution. The results show that the desired value of the tapped voltage can be achieved at any level of High Voltage (HV) with the selection of capacitors that are correctly rated. With an adequately designed control strategy, the research also shows that tapped voltage can be attained under both steady-state and dynamic loads. By leveraging CCS technology, the study demonstrates the potential for delivering reliable electricity to underserved areas, highlighting the system’s practicality and effectiveness in overcoming the limitations of conventional distribution methods.
基金supported by the National Natural Science Foundation of China(52477221,52202296)the Natural Science Foundation of Shaanxi Province(2023KXJ-246,2022JQ-048)。
文摘Metal-insulator-metal aluminium electrolytic capacitors(MIM-AECs)combine high capacity-density and high breakdown field strength of solid AECs with high-frequency responsibility,wide workingtemperature window and waterproof properties of MIM nanocapacitors.However,interfacial atomic diffusion poses a major obstacle,preventing the high-voltage MIM-AECs exploitation and thereby hampering their potential and advantages in high-power and high-energy-density applications.Here,an innovative high-voltage MIM-AECs were fabricated.The AlPO_(4)buffer layer is formed on AlO(OH)/AAO/Al surface by using H_(3)PO_(4)treatment,then a stable van der Waals(vdW)SnO_(2)/AlPO_(4)/AAO/Al multilayer was constructed via atomic layer deposition(ALD)technology.Due to higher diffusion barrier and lower carrier migration of SnO_(2)/AlPO_(4)/AAO interfaces,Sn atom diffusion is inhibited and carrier acceleration by electric field is weakened,guaranteeing high breakdown field strength of dielectric AAO and avoiding local breakdown risks.Through partial etching to hydrated AlO(OH)by H_(3)PO_(4)treatment,the tunnel was further opened up to facilitate subsequent ALD-SnO_(2)entry,thus obtaining a high SnO_(2)coverage.The SnO_(2)/AlPO_(4)/AAO/Al capacitors show a comprehensive performance in high-voltage(260 V),hightemperature(335℃),high-humidity(100%RH)and high-frequency response(100 k Hz),outperforming commercial solid-state AECs,and high-energy density(8.6μWh/cm^(2)),markedly exceeding previously reported MIM capacitors.The work lays the foundation for next-generation capacitors with highvoltage,high-frequency,high-temperature and high-humidity resistance.
文摘In the context of rapid economic development,the pursuit of sustainable energy solutions has become a major challenge.Lithium-ion capacitors(LICs),which integrate the high energy density of lithium-ion batteries with the high power density of supercapacitors,have emerged as promising candidates.However,challenges such as poor capacity matching and limited energy density still hinder their practical application.Carbon nanofibers(CNFs),with their high specific surface area,excellent electrical conductivity,mechanical flexibility,and strong compatibility with active materials,are regarded as ideal electrode frameworks for LICs.This review summarizes key strategies to improve the electrochemical performance of CNF-based LICs,including structural engineering,heteroatom doping,and hybridization with transition metal oxides.The underlying mechanisms of each approach are discussed in detail,with a focus on their roles in improving capacitance,energy density,and cycling stability.This review aims to provide insights into material design and guide future research toward high-performance LICs for next-generation energy storage applications.
文摘The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively applying mono-capacitor positioning, multiple positioning and reconfiguration processes using GA-based algorithms implemented in a Matlab environment. From the diagnostic study of this network, it was observed that a minimum voltage of 0.90 pu induces a voltage deviation of 5.26%, followed by active and reactive losses of 425.08 kW and 435.09 kVAR, respectively. Single placement with the NSGAII resulted in the placement of a 3000 kVAR capacitor at node 128, which proved to be the invariably neuralgic point. Multiple placements resulted in a 21.55% reduction in losses and a 0.74% regression in voltage profile performance. After topology optimization, the loss profile improved by 65.08% and the voltage profile improved by 1.05%. Genetic algorithms are efficient and effective tools for improving the performance of distribution networks, whose degradation is often dynamic due to the natural variability of loads.
基金financially supported by the National Natural Science Foundation of China(Nos.52001059,52072119)Hunan Provincial Natural Science Foundation(No.2023JJ50015)the 111 Project(No.D20015)。
文摘A pseudocapacitance dominated anode material assembled from Li_(3)VO_(4)nanocrystals encapsulated in the interlayers of N-doped graphene has been developed via a facile 2D nanospace confined strategy for lithium ion capacitors(LICs).In this contribution,the N-doped graphene synthesized by a faicle solid state reaction using C_(3)N_(4)nanosheets as template and glucose as carbon source provides sufficient 2D nanospace for the confined and homogeneous growth of Li_(3)VO_(4)at the nanoscale,and simultaneously efficiently anchors each nanobuilding block inside the interlayers,thus realizing the utilizaiton of full potential of active components.The so-formed 3D hybrids not only ensure intimate electronic coupling between active materials and N-doped graphene,but also realize robust structure integrity.Owing to these unique advantages,the resulting hybrids show pseudocapacitance dominated lithium storage behaviors with capacitive contributions of over 90%at both low and high current rates.The LVO@C@NG delivers reversible capacities of 206 mAh/g at 10 A/g,capacity retention of 92.7%after 1000 cycles at 2 A/g,and a high energy density of 113.6 Wh/kg at 231.8 W/kg for LICs.
文摘Reconfiguration,as well as optimal utilization of distributed generation sources and capacitor banks,are highly effective methods for reducing losses and improving the voltage profile,or in other words,the power quality in the power distribution system.Researchers have considered the use of distributed generation resources in recent years.There are numerous advantages to utilizing these resources,the most significant of which are the reduction of network losses and enhancement of voltage stability.Non-dominated Sorting Genetic Algorithm II(NSGA-II),Multi-Objective Particle Swarm Optimization(MOPSO),and Intersect Mutation Differential Evolution(IMDE)algorithms are used in this paper to perform optimal reconfiguration,simultaneous location,and capacity determination of distributed generation resources and capacitor banks.Three scenarios were used to replicate the studies.The reconfiguration of the switches,as well as the location and determination of the capacitor bank’s optimal capacity,were investigated in this scenario.However,in the third scenario,reconfiguration,and determining the location and capacity of the Distributed Generation(DG)resources and capacitor banks have been carried out simultaneously.Finally,the simulation results of these three algorithms are compared.The results indicate that the proposed NSGAII algorithm outperformed the other two multi-objective algorithms and was capable of maintaining smaller objective functions in all scenarios.Specifically,the energy losses were reduced from 211 to 51.35 kW(a 75.66%reduction),119.13 kW(a 43.54%reduction),and 23.13 kW(an 89.04%reduction),while the voltage stability index(VSI)decreased from 6.96 to 2.105,1.239,and 1.257,respectively,demonstrating significant improvement in the voltage profile.
基金National Natural Science Foundation of China (No. 22179123)Taishan Scholar Program of Shandong Province,China (No. tsqn202211048)Fundamental Research Funds for the Central Universities (No.202262010)。
文摘Zinc-ion hybrid capacitors (ZIHCs) have received increasing attention as energy storage devices owing to their low cost,high safety,and environmental friendliness.However,their progress has been hampered by low energy and power density,as well as unsatisfactory long-cycle stability,mainly due to the lack of suitable electrode materials.In this context,we have developed manganese single atoms implanted in nitrogen-doped porous carbon nanosheets (MnSAs/NCNs) using a metal salt template method as cathodes for ZIHCs.The metal salt serves a dual purpose in the synthesis process:It facilitates the uniform dispersion of Mn atoms within the carbon matrix and acts as an activating agent to create the porous structure.When applied in ZIHCs,the MnSAs/NCNs electrode demonstrates exceptional performance,including a high capacity of 203 m Ah g^(-1),an energy density of 138 Wh kg^(-1)at 68 W kg^(-1),and excellent cycle stability with 91%retention over 10,000 cycles.Theoretical calculations indicate that the introduced Mn atoms modulate the local charge distribution of carbon materials,thereby improving the electrochemical property.This work demonstrates the significant potential of carbon materials with metal atoms in zinc-ion hybrid capacitors,not only in enhancing electrochemical performance but also in providing new insights and methods for developing high-performance energy storage devices.
基金supported by the National Natural Science Foundation of China(22408061 and 22468005)Program for Introducing High-Level Talents from Guangxi University,and Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology(2023Z014).
文摘Oxygen-rich porous carbons are promising candidates for the carbon-based cathodes of zinc ion hybrid capacitors(ZIHCs).Potassium activation is a traditional and effective way to prepare oxygen-rich porous carbons.Efficient potassium activation is the key to develop high-performance oxygen-rich porous carbon cathodes.Herein,the alkali lignin,extracted from eucalyptus wood by geopolymer-assisted low-alkali pretreatment,is used to prepare oxygen-rich lignin-derived porous carbons(OLPCs)through KOH activation and K_(2)CO_(3)activation at 700-900℃.KOH activation constructs a hierarchical micro-mesoporous structure,while K_(2)CO_(3)activation constructs a microporous structure.Furthermore,K_(2)CO_(3)activation could more efficiently construct active oxygen(C=O)species than KOH activation.The OLPCs prepared by KOH/K_(2)CO_(3)activations at 800℃show the highest microporosity(78.4/87.7%)and C=O content(5.3/8.0 at.%).Due to that C=O and micropore adsorb zinc ions,the OLPCs prepared by K_(2)CO_(3)activation at 800℃with higher C=O content and microporosity deliver superior capacitive performance(256 F g^(-1)at 0.1 A g^(-1))than that by KOH activation at 800℃(224 F g^(-1)at 0.1 A g^(-1)),and excellent cycling stability.This work provides a new insight into the sustainable preparation of oxygenrich porous carbon cathodes through efficient potassium activation for ZIHCs.
基金supported by China Yangtze Power Co.,Ltd.(No.ZSF2502001).
文摘Submodule capacitor aging poses significant challenges to the safe operation of modular multilevel converter(MMC)systems.Traditional detection methods rely predominantly on offline tests,lacking real-time evaluation capabilities.Moreover,existing online approaches require additional sampling channels,thereby increasing system complexity and costs.To address these issues,this paper proposes an online evaluation method for submodule capacitor aging based on CapAgingNet.Initially,an MMC system simulation platform is developed to examine the effects of submodule capacitor aging on system operational characteristics and to create a dataset of submodule capacitor switching states.Subsequently,the CapAgingNet model is introduced,incorporating key technical modules to enhance performance:the Deep Stem module,which extracts larger receptive fields through multiple convolution layers and mitigates the impact of data sparsity in capacitor aging on feature extraction;the efficient channel attention(ECA)module,utilizing onedimensional convolution for dynamic weighting to adjust the importance of each channel,thereby enhancing the ability of the model to process high-dimensional features in capacitor aging data;and the multiscale feature fusion(MSF)module,which integrates capacitor aging information across different scales by combining fine-grained and coarse-grained features,thus improving the capacity of the model to capture high-frequency variation characteristics.The experimental results reveal that the CapAgingNet model achieves a TOP-1 accuracy of 95.32%and a macro-averaged F1 score of 95.49%on the test set,thereby providing effective technical support for online monitoring of submodule capacitor aging.
基金Natural Science Foundation of Xinjiang Uygur Autonomous Region,Grant/Award Number:2023D01C11National Natural Science Foundation of China,Grant/Award Numbers:22369019,U2003216+2 种基金Special Projects on Regional Collaborative Innovation-SCO Science and Technology Partnership Program,International Science and Technology Cooperation Program,Grant/Award Number:2022E01020Tianshan Talent Training Program,Grant/Award Number:2023TSYCLJ0019National Key Research and Development Program of China,Grant/Award Numbers:2022YFB4101600,2022YFB4101601。
文摘The rise of Zn-ion hybrid capacitor(ZHC)has imposed high requirements on carbon cathodes,including reasonable configuration,high specific surface area,multiscale pores,and abundant defects.To achieve this objective,a template-oriented strategy coupled with multi-heteroatom modification is proposed to precisely synthesize a three-dimensional boron/nitrogen-rich carbon nanoflake-interconnected micro/nano superstructure,referred to as BNPC.The hierarchically porous framework of BNPC shares short channels for fast Zn2+transport,increased adsorption-site accessibility,and structural robustness.Additionally,the boron/nitrogen incorporation effect significantly augments Zn2+adsorption capability and more distinctive pseudocapacitive nature,notably enhancing Zn-ion storage and transmission kinetics by performing the dual-storage mechanism of the electric double-layer capacitance and Faradaic redox process in BNPC cathode.These merits contribute to a high capacity(143.7 mAh g^(-1)at 0.2 A g^(-1))and excellent rate capability(84.5 mAh g^(-1)at 30 A g^(-1))of BNPC-based aqueous ZHC,and the ZHC still shows an ultrahigh capacity of 108.5 mAh g^(-1)even under a high BNPC mass loading of 12 mg cm^(-2).More critically,the BNPC-based flexible device also sustains notable cyclability over 30,000 cycles and low-rate self-discharge of 2.13 mV h-1 along with a preeminent energy output of 117.15 Wh kg^(-1)at a power density of 163.15Wkg^(-1),favoring a creditable applicability in modern electronics.In/ex-situ analysis and theoretical calculations elaborately elucidate the enhanced charge storage mechanism in depth.The findings offer a promising platform for the development of advanced carbon cathodes and corresponding electrochemical devices.
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.92372122 and 52471242)the Fundamental Research Funds for the Central Universities,China(Nos.GG2060127001,KY2060000150,and WK2060000040)supported by the Joint Laboratory for USTC and Yanchang Petroleum,China(No.2022ZK-03)。
文摘Along with the surging demand for energy storage devices,the cost and availability of the materials remain dominant factors in slowing down their industrial application.The repurposing of waste asphalt into high-performance electrode materials is of significant interest,as it holds the potential to circumvent energy and environmental issues.Here,we report the controllable synthesis of asphalt-derived mesoporous carbon as an active material for electrocatalytic hydrogen gas capacitor(EHGC).The hierarchically porous carbon(HPC)with a high surface area of 1943.4 m^(2)·g^(-1)can operate in pH universal aqueous electrolytes in EHGC.It displays a specific energy and power density of 57 Wh·kg^(-1)and 554 W·kg^(-1)in neutral electrolyte as well as 52 Wh·kg^(-1)and 657 W·kg^(-1)in acidic electrolyte.Additionally,the charge storage mechanism of HPC-EHGC is studied with the help of Raman spectroscopy and X-ray photoelectron spectroscopy.Furthermore,the assembled HPC-EHGC device displays a discharge capacitance of 170 F·g^(-1)with an excellent capacitance retention rate of 100%up to 20000 cycles at 10 A·g^(-1)in acidic electrolyte.This work introduces a novel approach to converting waste asphalt into high-performance carbon for EHGC,achieving superior performance over commercial materials.By simultaneously addressing environmental waste issues and advancing energy storage technology,this study makes a significant contribution to sustainable materials science and next-generation battery development.
基金support from National Outstanding Youth Science Fund(52222314)Near Space Technology and Industry Guidance Fund Project(LKJJ-2023010-01)+3 种基金CNPC Innovation Found(2021DQ02-1001)Dalian Outstanding Youth Science and Technology Talent Project(2023RJ006)Dalian Science and Technology Innovation Project(2022JJ12GX022)Xinghai Talent Cultivation Plan(X20200303).
文摘Sodium-ion hybrid capacitors(SICs),which combine the high energy density of batteries with the high power density and long cycle life of capacitors,are considered promising next-generation energy storage devices.Ensuring the performance of SICs in low-temperature environments is crucial for applications in high-altitude cold regions,where the desolvation process of Na+and the transport process in the solid electrolyte interphase(SEI)are determinant.In this paper,we proposed a multi-ether modulation strategy to construct a solvation sheath with multi-ether participation by modulating the coordination of Na+and solvents.This unique solvation sheath not only reduces the desolvation energy barrier of Na+,but more importantly forms a Na_(2)O-rich inorganic SEI and enhances the ionic dynamics of Na+.Benefiting from the excellent solvation structure design,SICs prepared with this electrolyte can achieve energy density of up to 178 Wh·kg^(-1) and ultra-high power density of 42390 W·kg^(-1) at room temperature.Notably,this SIC delivers record-high energy densities of 149 Wh·kg^(-1) and 119 Wh·kg^(-1) as well as power densities of up to 25200 W·kg^(-1) and 24591 W·kg^(-1) at−20℃ and−40℃,respectively.This work provides new ideas for the development of high-performance SICs for low-temperature operating environments.
基金supported by the National Natural Science Foundation of China(Nos.52071171,52202248)Liaoning BaiQianWan Talents Program(LNBQW2018B0048)+8 种基金Shenyang Science and Technology Project(21-108-9-04)Key Research Project of Department of Education of Liaoning Province(LJKZZ20220015)the Research Fund for the Doctoral Program of Liaoning Province(2022-BS-114)Chunhui Program of the Ministry of Education of the People’s Republic of China(202201135)Australian Research Council(ARC)through Future Fellowship(FT210100298,FT210100806)Discovery Project(DP220100603)Linkage Project(LP210100467,LP210200504,LP210200345,LP220100088)Industrial Transformation Training Centre(IC180100005)schemes,and the Australian Government through the Cooperative Research Centres Projects(CRCPXIII000077)the Australian Renewable Energy Agency(ARENA)as part of ARENA’s Transformative Research Accelerating Commercialisation Program(TM021).
文摘The advancement of aqueous magnesium ion energy storage devices encounters limitations due to the substantial hydration radius of magnesium ions(Mg^(2+))and their strong electrostatic interaction with the primary material.Consequently,this study successfully developed a MnS/MnO heterostructure through a straightforward hydrothermal and annealing method,marking its initial application in aqueous magnesium ion capacitors(AMICs).The fabricated MnS/MnO heterostructure,characterized by S defects,also generates Mn defects via in-situ initiation of early electrochemical processes.This unique dual ion defects MnS/MnO heterostructure(DID-MnS/MnO)enables the transformation of MnS and MnO,initially not highly active electrochemically for Mg^(2+),into cathode materials exhibiting high electrochemical activity and superior performance.Moreover,DID-MnS/MnO enhances conductivity,improves the kinetics of surface redox reactions,and increases the diffusion rate of Mg^(2+).Furthermore,this study introduces a dual energy storage mechanism for DID-MnS/MnO,which,in conjunction with dual ion defects,offers additional active sites for Mg^(2+)insertion/deinsertion in the host material,mitigating volume expansion and structural degradation during repeated charge-discharge cycles,thereby significantly enhancing cycling reversibility.As anticipated,using a three-electrode system,the developed DID-MnS/MnO demonstrated a discharge specific capacity of 237.9 mAh/g at a current density of 0.1 A/g.Remarkably,the constructed AMIC maintained a capacity retention rate of 94.3%after 10000 cycles at a current density of 1.0 A/g,with a specific capacitance of 165.7 F/g.Hence,DID-MnS/MnO offers insightful perspectives for designing alternative clean energy sources and is expected to contribute significantly to the advancement of the clean energy sector.
基金Project supported in part by the Science and Technology Development Plan Project of Jilin Province, China (Grant No. YDZJ202303CGZH022)the National Key Research and Development Program of China (Grant No. 2024YFE0205300)+1 种基金the National Natural Science Foundation of China (Grant No. 62471504)the Open Fund of the State Key Laboratory of Optoelectronic Materials and Technologies (Sun Yat-Sen University) (Grant No. OEMT-2023KF-05)。
文摘Metal–insulator–semiconductor(MOS) capacitor is a key structure for high performance MOS field transistors(MOSFETs), requiring low leakage current, high breakdown voltage, and low interface states. In this paper, β-Ga_(2)O_(3) MOS capacitors were fabricated with ALD deposited Al_(2)O_(3) using H_(2)O or ozone(O_(3)) as precursors. Compared with the Al_(2)O_(3) gate dielectric with H_(2)O as ALD precursor, the leakage current for the O_(3) precursor case is decreased by two orders of magnitude, while it keeps the same level at the fixed charges, interface state density, and border traps. The SIMS tests show that Al_(2)O_(3) with O_(3) as precursor contains more carbon impurities. The current transport mechanism analysis suggests that the C–H complex in Al_(2)O_(3) with O_(3) precursor serves as deep energy trap to reduce the leakage current. These results indicate that the Al_(2)O_(3)/β-Ga_(2)O_(3)MOS capacitor using the O_(3) precursor has a low leakage current and holds potential for application in β-Ga_(2)O_(3) MOSFETs.
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)+3 种基金China Postdoctoral Science Foundation(2022M712402)Shanghai Rising-Star Program(23YF1449200)Zhejiang Provincial Science and Technology Project(2022C01182)the Fundamental Research Funds for the Central Universities(22120210529 and 2023-3-YB-07)。
文摘Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical behaviors,yet has not been unraveled.Here we propose an NH_(4)^(+)-modulated cationic solvation strategy to optimize cathodic spatial charge distribution and achieve dynamic Zn^(2+)/NH_(4)^(+)co-storage for boosting Zinc hybrid capacitors.Owing to the hierarchical cationic solvated structure in hybrid Zn(CF_(3)SO_(3))_(2)–NH_4CF_(3)SO_(3)electrolyte,high-reactive Zn^(2+)and small-hydrate-sized NH_4(H_(2)O))(4)^(+)induce cathodic interfacial Helmholtz plane reconfiguration,thus effectively enhancing the spatial charge density to activate 20%capacity enhancement.Furthermore,cathodic interfacial adsorbed hydrated NH_(4)^(+)ions afford high-kinetics and ultrastable C···H(NH_(4)^(+))charge storage process due to a much lower desolvation energy barrier compared with heavy and rigid Zn(H_(2)O)_6^(2+)(5.81 vs.14.90 eV).Consequently,physical uptake and multielectron redox of Zn^(2+)/NH_(4)^(+)in carbon cathode enable the zinc capacitor to deliver high capacity(240 mAh g^(-1)at 0.5 A g^(-1)),large-current tolerance(130 mAh g^(-1)at 50 A g^(-1))and ultralong lifespan(400,000cycles).This study gives new insights into the design of cathode–electrolyte interfaces toward advanced zinc-based energy storage.
文摘Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected.
基金supported by the National Natural Science Foundation of China(Nos.52004338,22378431)Hunan Provincial Natural Science Foundation(Nos.2022JJ20075,2023JJ40210)+1 种基金Scientific Research Fund of Hunan Provincial Education Department(No.21B0017)Central South University Innovation-Driven Research Programme(No.2023CXQD008)。
文摘The exploration of advanced materials through rational structure/phase design is the key to develop highperformance lithium-ion capacitors(LICs).However,high complexity of material preparation and difficulty in quantity production largely hinder the further development.Herein,Cu_(5)FeS_(4-x)/C(CFS@C)heterojunction with rich sulfur vacancies has successfully achieved from natural bornite,presenting low costeffective and bulk-production prospect.Density functional theory(DFT)calculations indicate that rich vacancies in bulk phase can decrease band gap of bornite and thus improve its intrinsic electron conductivity,as well as the heterojunction spontaneously evokes a built-in electric field between its interfacial region,largely reducing the migration barrier from 1.27 e V to 0.75 e V.Benefited from these merits,the CFS@C electrodes deliver outperformed lithium storage performance,e.g.,high reversible capacity(822.4m Ah/g at 0.1 A/g),excellent cycling stability(up to 820 cycles at 2 A/g and 540 cycles at 5 A/g with respective capacity retention of over or nearly 100%).With CFS@C as anode and porous carbon nanosheets(PCS)as cathode,the assembled CFS@C//PCS LIC full cells exhibit high energy/power density characteristics of 139.2 Wh/kg at 2500 W/kg.This work is expected to offer significant insights into structure modifications/devising toward natural minerals for advanced energy-storage systems.
基金supported in part by the CAS Project for Young Scientists in Basic Research under Grant No. YSBR-045the Youth Innovation Promotion Association CAS under Grant 2022137the Institute of Electrical Engineering CAS under Grant E155320101。
文摘Cascaded H-bridge inverter(CHBI) with supercapacitors(SCs) and dc-dc stage shows significant promise for medium to high voltage energy storage applications. This paper investigates the voltage balance of capacitors within the CHBI, including both the dc-link capacitors and SCs. Balance control over the dc-link capacitor voltages is realized by the dcdc stage in each submodule(SM), while a hybrid modulation strategy(HMS) is implemented in the H-bridge to balance the SC voltages among the SMs. Meanwhile, the dc-link voltage fluctuations are analyzed under the HMS. A virtual voltage variable is introduced to coordinate the balancing of dc-link capacitor voltages and SC voltages. Compared to the balancing method that solely considers the SC voltages, the presented method reduces the dc-link voltage fluctuations without affecting the voltage balance of SCs. Finally, both simulation and experimental results verify the effectiveness of the presented method.
