High-entropy oxides(HEOs),offering reversible lithium storage and moderate operating potential,are considered promising negative electrodes.However,the intricate lithium storage mechanism within HE polycationic system...High-entropy oxides(HEOs),offering reversible lithium storage and moderate operating potential,are considered promising negative electrodes.However,the intricate lithium storage mechanism within HE polycationic systems remains challenging.Here,we conduct comprehensive investigations into the electrochemical properties and structu ral evolution of(CrMnCoNiZn)_(3)O_(4)(HESO)to clarify lithium storage mechanisms.Density functional theory(DFT)calculations reveal that polycationic synergy modulates the electronic structure and d-band centers of HESO,delivering fast electrode kinetics.Exhaustive in-and exsitu analyses demonstrate that the residual crystalline phases acting as seed crystals maintain the spinel/rock-salt lattice persistence under the entropy stabilization effect,lattice distortion effect,and cation synergy,which guide cation crystallization upon the electric field to drive reversible lithium storage.Such properties underlie the HESO electrode with an exceptional rate and long-term capability.This work clarifies the roles of cationic synergy and seed-crystal-driven structural reversibility,providing a blueprint for designing high-performance HEO negative electrodes for next-generation lithium-ion batteries(LIBs).展开更多
Rechargeable magnesium batteries(RMBs)have attracted much attention due to the high theoretical capacity(3833 mAh cm−3)of magnesium metal negative electrode and abundant resources.However,the preparation of ultra-thin...Rechargeable magnesium batteries(RMBs)have attracted much attention due to the high theoretical capacity(3833 mAh cm−3)of magnesium metal negative electrode and abundant resources.However,the preparation of ultra-thin magnesium foils faces the problems of rolling difficulty and high processing cost,while the use of thick magnesium foils leads to low utilization of magnesium and reduces the energy density.To tackle the above problems,we successfully prepared ultra-thin magnesium foils based on electrolytic process and investigated the effect of different substrates.The magnesium foils prepared using Mo substrate have more uniform surface morphology and lower surface roughness,which is attributed to the lower magnesium nucleation overpotential of Mo substrate.Meanwhile,density functional theory calculations show that the adsorption energy of Mo on Mg is more negative,which is conducive to achieving uniform nucleation and deposition of Mg.The Mg deposition on Mo substrate undergoes the characteristic stages of transient nucleation,nucleus accretion,multidirectional heterotopic growth,and columnar crystal stacking,and ultimately the formation of a dense deposited layer.In addition,the prepared ultra-thin Mg foil with Mo substrate can stably cycle for 1000 h at 3 mA cm^(-2) with high utilization of 50% in the symmetric cell.This study develops a facile method for the preparation of ultra-thin Mg foils,which opens up a new path for developing high-performance ultra-thin negative electrodes for RMBs.展开更多
The low specific capacitances(SCs)of traditional carbonaceous negative electrodes significantly limit the enhancement in energy density of aqueous hybrid supercapacitors(AHCs).It is still hugely challengeable to explo...The low specific capacitances(SCs)of traditional carbonaceous negative electrodes significantly limit the enhancement in energy density of aqueous hybrid supercapacitors(AHCs).It is still hugely challengeable to explore a candidate with large SCs,which can stably operate in the negative potential region mean-while.For this propose,we design and fabricate solid-solution Ru_(x)Cu_(1-x)O_(2) nanocrystals(NCs),which exhibit competitive SCs and electrochemical stability within the potential range from-0.9 V to 0.0 V in the aqueous KOH electrolyte.The incorporation of Cu enhances the electrochemical utilization of RuO_(2),reaction kinetics,electronic conductivity,and hydrogen evolution overpotentials,which are all highly dependent upon the added contents of Cu species.The optimized Ru_(0.8)Cu_(0.2)O_(2)(RuCu82)electrode of a high mass loading of 5 mg cm^(-2) reveals the best electrochemical capacitances in terms of reversible SCs and capacitance degradation at room temperature and-20℃.Furthermore,the reversible K^(+)-(de)intercalation induced pseudocapacitance is proposed for electrochemical charge storage process of RuCu82.In particu-lar,remarkable specific energy of 59.1 Wh kg-1 at 400 W kg-1 and excellent cycling stability are achieved in the assembled NiCoO_(2)//RuCu82 AHCs.Our contribution here presents a new promising negative elec-trode platform with high SCs and electrochemical stability for next-generation AHCs.展开更多
Carbon materials,including graphite,hard carbon,soft carbon,graphene,and carbon nanotubes,are widely used as high-performance negative electrodes for sodium-ion and potassium-ion batteries(SIBs and PIBs).Compared with...Carbon materials,including graphite,hard carbon,soft carbon,graphene,and carbon nanotubes,are widely used as high-performance negative electrodes for sodium-ion and potassium-ion batteries(SIBs and PIBs).Compared with other materials,carbon materials are abundant,low-cost,and environmentally friendly,and have excellent electrochemical properties,which make them especially suitable for negative electrode materials of SIBs and PIBs.Compared with traditional carbon materials,modifications of the morphology and size of nanomaterials represent effective strategies to improve the quality of electrode materials.Different nanostructures make different contributions toward improving the electrochemical performance of electrode materials,so the synthesis of nanomaterials is promising for controlling the morphology and size of electrode materials.This paper reviews the progress made and challenges in the use of carbon materials as negative electrode materials for SIBs and PIBs in recent years.The differences in Na+and K+storage mechanisms among different types of carbon materials are emphasized.展开更多
Nano-silicon(nano-Si)and its composites have been regarded as the most promising negative electrode materials for producing the next-generation Li-ion batteries(LIBs),due to their ultrahigh theoretical capacity.Howeve...Nano-silicon(nano-Si)and its composites have been regarded as the most promising negative electrode materials for producing the next-generation Li-ion batteries(LIBs),due to their ultrahigh theoretical capacity.However,the commercial applications of nano Si-based negative electrode materials are constrained by the low cycling stability and high costs.The molten salt electrolysis of SiO_(2)is proven to be suitable to produce nano-Si with the advantages of in-situ microstructure control possibilities,cheap affordability and scale-up process capability.Therefore,an economical approach for electrolysis,with a SiO_(2)/graphite porous electrode as cathode,is adopted to produce nano-Si/graphite composite negative electrode materials(SGNM)in this study.The electrolytic product of the optimized porous electrode is taken as the negative electrode materials for LIBs,and it offers a capacity of 733.2 mAh·g^(-1)and an initial coulombic efficiency of 86.8%in a coin-type cell.Moreover,the capacity of the SGNM retained 74.1%of the initial discharging capacity after 50 cycles at 0.2C,which is significantly higher than that of the simple mixture of silicon and graphite obtained from the formation of silicon carbide(SiC)between nano-Si and graphite particles.Notably,this new approach can be applied to a large-scale production.展开更多
The complex-architectured NiFe-LDH@FeOOH negative material was first prepared by simple two-step hydrothermal method.In this study,the porous nanostructure of FeOOH nanosheets features a large number of accessible cha...The complex-architectured NiFe-LDH@FeOOH negative material was first prepared by simple two-step hydrothermal method.In this study,the porous nanostructure of FeOOH nanosheets features a large number of accessible channels to electroactive sites and the two-dimensional layered structure of NiFe-LDH nanosheets have an open spatial structure with high specific surface area,which enhance the diffusion of ions in the active material.Benefited from above advantages,the excellent electrochemical properties were demonstrated.NiFe-LDH@FeOOH nanocomposites present high specific capacitance(1195 F/g at a current density of 1 A/g),lower resistance and well cycling performance(90.36% retention after 1000 cycles).Furthermore,the NiFe-LDH@MnO2//NiFe-LDH@FeOOH supercapacitor exhibits22.68 Wh/kg energy density at 750 W/kg power density,demonstrating potential application in energy storage devices.展开更多
A composite In-Pb:carbon was successfully synthetized by a two-step mechanochemical synthesis in order to obtain an adequate particles size and structure to investigate the electrochemical reactivity of the In-Pb soli...A composite In-Pb:carbon was successfully synthetized by a two-step mechanochemical synthesis in order to obtain an adequate particles size and structure to investigate the electrochemical reactivity of the In-Pb solid solution towards Mg.A potential synergetic coupling of electroactive elements In and Pb was examined using electrochemical and ex situ X-ray diffraction analyses.The potential profile of the solid solution indicates the formation of Mg_(2)Pb and Mg In.However,the diffraction study suggests a peculiar electrochemically-driven amorphization of Mg In during the magnesiation,in strong contrast to Mg In crystallization in In-based and In Bi-based electrodes reported in the literature.Combining In and Pb favors the amorphization of Mg In and a high first magnesiation capacity of about 550 m Ah g^(-1),but is thereafter detrimental to the material’s reversibility.These results emphasize the possible influence of electrochemically-driven amorphization and crystallization processes on electrochemical performance of battery materials.展开更多
Lead-carbon hybrid capacitors are the electrochemical devices between supercapacitors and lead-acid batteries,with low prices,stability in high and low temperature,good security and broad application prospects.This pa...Lead-carbon hybrid capacitors are the electrochemical devices between supercapacitors and lead-acid batteries,with low prices,stability in high and low temperature,good security and broad application prospects.This paper introduces an electrodeposition behavior of Pb^(2+)on the negative electrode,which can improve the cycle life of the lead-carbon hybrid capacitor.During the charging process,lead ions in the electrolyte can diffuse from the positive electrode of the lead-carbon hybrid capacitor into the negative electrode.When charging at a low current density,the lead ions around the negative electrode can be reduced to lead,and it is then quickly converted to lead sulfate crystals.With the increase of the number of cycles,the final result is sulfation.Sulfation can reduce the specific surface area of the electric double layer,thereby reducing the capacitance performance of the carbon material.As a result,it reduces the charge-discharge efficiency of the lead-carbon hybrid capacitor.The service life of lead-carbon hybrid capacitor is significantly improved by the inhibition of lead deposition by anion exchange membrane.The capacity retention rate at 5 A/g is improved from 84%after 1000 cycles to 95%after 10,000 cycles.The discovery of lead deposition in the negative electrode is conducive to improving the performance of long-life lead-carbon hybrid capacitors.展开更多
Metal aluminum batteries(MABs)are considered potential large-scale energy storage devices because of their high energy density,resource abundance,low cost,safety,and environmental friendliness.Given their high electri...Metal aluminum batteries(MABs)are considered potential large-scale energy storage devices because of their high energy density,resource abundance,low cost,safety,and environmental friendliness.Given their high electrical conductivity,high theoretical specific capacity,and high discharge potential,Te is considered a potential positive electrode material for MABs.Nonetheless,the critical issues induced by the chemical and electrochemical dissolution of tellurium and subsequent chemical precipitation on bare Al negative electrodes result in poor cycle stability and low discharge capacity of Al-Te batteries.Here an efficient TiB_(2)-based modified layer has been proposed to address bare Al electrodes(Al/TB).Consequently,the low-voltage hysteresis and long cycle life of the Al/TB negative electrode have been achieved.In addition,the electrochemical performance of the Al-Te battery based on the Al/TB negative electrode is dramatically improved.Furthermore,the modified separator technology is introduced to match with the as-designed Al/TB negative electrode.Therefore,the record-setting long-term cycle stability of up to 500 cycles has been achieved in the Al-Te battery.The facile strategy also opens a potential route for other high-energy density battery systems,such as Al-S and Al-Se batteries.展开更多
The degradation mechanism of an Sn_4P_3 electrode as Na-ion battery anode was investigated by using a transmission electron microscopic observation. At the first desodiation, we confirmed that Sn nanoparticles with 6 ...The degradation mechanism of an Sn_4P_3 electrode as Na-ion battery anode was investigated by using a transmission electron microscopic observation. At the first desodiation, we confirmed that Sn nanoparticles with 6 nm in size were dispersed in an amorphous-like P matrix.Compared to this, we observed aggregated Sn particles with sizes exceeding 50 nm after the drastic capacity fading. The capacity fading mechanism was for the first time confirmed to be Sn aggregation. To improve the capacity decay, we carried out the two kinds of chargeàdischarge cycling tests under the reduced volume changes of Sn particles and P matrix by limiting desodiation reactions of Nae Sn and Na3P, respectively. The Sn_4P_3 electrode exhibited an excellent cyclability with the discharge capacity of 500 mA hg^(-1) for 420 cycles under the limited desodiation, whereas the capacity decay was accelerated under the limited sodiation. The results suggest that the Sn aggregation can be improved by the reduced volume change of the P matrix, and that it is very effective for improving anode performance of Sn_4P_3 electrode.展开更多
Development of electrodes with high electrocatalytic activity and stability is essential for solving problems that still restrict the extensive application of vanadium redox flow batteries(VRFBs).Here,we designed a no...Development of electrodes with high electrocatalytic activity and stability is essential for solving problems that still restrict the extensive application of vanadium redox flow batteries(VRFBs).Here,we designed a novel negative electrode with superior electrocatalytic activity by tailoring nitrogen functional groups,such as newly formed nitro and pyridinic-N transformed to pyridonic-N,from the prenitrogen-doped electrode.It was experimentally confirmed that an electrode with pyridonic-N and nitro fuctional groups(tailored nitrogen-doped graphite felt,TNGF) has superior electrocatalytic acivity with enhanced electron and mass transfer.Density functional theory calulations demonstrated the pyridonic-N and nitro functional groups promoted the adsorption,charge transfer,and bond formation with the vanadium species,which is consistent with expermental results.In addition,the V2+/V3+redox reaction mechanism on pyridonic-N and nitro functional groups was estabilised based on density functional theory(DFT) results.When TNGF was applied to a VRFB,it enabled enhanced-electrolyte utilization and energy efficiencies(EE) of 57.9% and 64.6%,respectively,at a current density of 250 mA cm^(-2).These results are 18.6% and 8.9% higher than those of VRFB with electrode containing graphitic-N and pyridinicN groups.Interestingly,TNGF-based VRFB still operated with an EE of 59% at a high current density of300 mA cm^(-2).The TNGF-based VRFB exhibited stable cycling performance without noticeable decay of EE over 450 charge-discharge cycles at a current density of 250 mA cm^(-2).The results of this study suggest that introducing pyridonic-N and nitro groups on the electrode is effective for improving the electrochemical performance of VRFBs.展开更多
Nanoporous anatase TiO_2 （np-TiO_2） electrodes have been developed via the anodization of titanium foils in fluoride containing electrolytes, and its application in rechargeable lithium-ion batteries （LIBs） was in...Nanoporous anatase TiO_2 （np-TiO_2） electrodes have been developed via the anodization of titanium foils in fluoride containing electrolytes, and its application in rechargeable lithium-ion batteries （LIBs） was investigated. Four different types of np-TiO_2 electrodes with different pore diameters of 14.7±8.2 nm, 12.85±6.8 nm, 11.0±5.5, and 26.7±13.6 nm were fabricated for evaluating the effect of nanoporous characteristics on the LIB performance. The discharge capacity of the four battery types 1, 2, 3, and 4 were 132.7 mAh·g^-1, 316.7 mAh·g^-1, 154.3 mAh·g^-1, and 228.4 mAh·g^-1, respectively. In addition, these electrodes 1, 2, 3, and 4 exhibited reversible capacity of 106.9 mAh·g^-1 after 295th, 180.9 mAh·g^-1 after 220th, 126.1 mAh·g^-1 after 150th, and 206.7 mAh·g^-1 after 85th cycle at a rate of 1 C, respectively. It was noted that the cyclic life of the batteries had an inverse relationship, and the capacity had a proportional relationship to the pore diameter. The enhanced electrochemical performance of the nanoporous electrodes can be attributed to the improved conductivity and the enhanced kinetics of lithium insertion/extraction at electrode/electrolyte interfaces because of the large specific surface area of np-TiO_2 electrodes.展开更多
The electronic transport properties of a single thiolated arylethynylene molecule with 9,10-dihydroanthracene core, denoted as TADHA, is studied by using non-equilibrium Green＇s function formalism combined with ab in...The electronic transport properties of a single thiolated arylethynylene molecule with 9,10-dihydroanthracene core, denoted as TADHA, is studied by using non-equilibrium Green＇s function formalism combined with ab initio calculations. The numerical results show that the TADHA molecule exhibits excellent negative differential conductance （NDC） behavior at lower bias regime as probed experimentally. The NDC behavior of TADHA molecule originates from the Stark effect of the applied bias voltage, by which the highest occupied molecular orbital （HOMO） and the HOMO-1 are pulled apart and become localized. The NDC behavior of TADHA molecular system is tunable by changing the electrode distance. Shortening the electrode separation can enhance the NDC effect which is attributed to the possible increase of coupling between the two branches of TADHA molecule.展开更多
Anodic oxidation with different electrolyte was employed to improve the electrochemical properties of carbon paper as negative electrode for vanadium redox battery(VRB).The treated carbon paper exhibits enhanced elect...Anodic oxidation with different electrolyte was employed to improve the electrochemical properties of carbon paper as negative electrode for vanadium redox battery(VRB).The treated carbon paper exhibits enhanced electrochemical activity for V^2+/V^3+redox reaction.The sample(CP-NH3)treated in NH3 solution demonstrates superior performance in comparison with the sample(CP-NaOH)treated in NaOH solution.X-ray photoelectron spectroscopy results show that oxygen-and nitrogen-containing functional groups have been introduced on CP-NH3 surface by the treatment,and Raman spectra confirm the increased surface defect of CP-NH3.Energy storage performance of cell was evaluated by charge/discharge measurement by using CP-NH3.Usage of CP-NH3 can greatly improve the cell performance with energy efficiency increase of 4.8%at 60 mA/cm^2.The excellent performance of CP-NH3 mainly results from introduction of functional groups as active sites and improved wetting properties.This work reveals that anodic oxidation is a clean,simple,and efficient method for boosting the performance of carbon paper as negative electrode for VRB.展开更多
Many sub-products of pulsed discharge,such as ultraviolet light,strong electric fields,shock waves and active species,are effective in treating wastewater.To improve the efficiency of the discharge plasma technology i...Many sub-products of pulsed discharge,such as ultraviolet light,strong electric fields,shock waves and active species,are effective in treating wastewater.To improve the efficiency of the discharge plasma technology in removing pollutants,adding TiO2 photo-catalyst to pulsed discharges could help.A negative-pulsed-discharge system,which has nozzle discharge electrodes with or without TiO2 coating,is used to degrade azo dye Acid OrangeⅡ,and the effects of several key conditions(maximum pulse voltage,pulse repetition frequency,initial mass concentration of Acid OrangeⅡinitial solution pH,treatment duration,the phase of discharge,and the existence of TiO2)on the degradation are experimentally investigated.The degradation of Acid OrangeⅡincreases with maximum pulse voltage,pulse repetition frequency,and treatment duration,and it is larger when putting the discharge electrode on the solution surface than in air or inside the solution,i.e.the discharge in gas phase is more effective than that in gas-liquid phase or liquid phase.The degradation decreases as the initial mass concentration of the solution increases.It also relates to pH and is higher at acidic conditions than at neutral or alkaline conditions.Compared to treatments without TiO2,the ones using the nozzle discharge electrode with TiO2 coated increase the degradation of Acid OrangeⅡby 5%.It is concluded that the proposed system with TiO2 added in can remove Acid OrangeⅡfrom wastewater effectively.展开更多
The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods.The nozzle-cylinder electrode in the discharge reactor was supplied witha negative nanosecond puls...The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods.The nozzle-cylinder electrode in the discharge reactor was supplied witha negative nanosecond pulsed generator.The optical emission spectrum diagnosis revealed that OH（A2∑＋ → X2Π,306–309 nm）,N32（CΠ→B3Πg,337 nm）,O（3p5p→3s-5s-0,777.2 nm）and O（3p3p→3s3s0,844.6 nm）were produced in the discharge plasma channels.The electron temperature（Te）was calculated from the emission relative intensity ratio between the atomic O 777.2 nm and 844.6 nm,and it increased with the applied voltage and the pulsed frequency and fell within the range of 0.5–0.8 e V.The gas temperature（Tg）that was measured by Lifbase was in a range from 400 K to 600 K.展开更多
Pseudo-capacitive negative electrodes remain a major bottleneck in the development of supercapacitor devices with high energy density because the electric double-layer capacitance of the negative electrodes does not m...Pseudo-capacitive negative electrodes remain a major bottleneck in the development of supercapacitor devices with high energy density because the electric double-layer capacitance of the negative electrodes does not match the pseudocapacitance of the corresponding positive electrodes.In the present study,a strategically improved Ni-Co-Mo sulfide is demonstrated to be a promising candidate for high energy density supercapattery devices due to its sustained pseudocapacitive charge storage mechanism.The pseudocapacitive behavior is enhanced when operating under a high current through the addition of a classical Schottky junction next to the electrode-electrolyte interface using atomic layer deposition.The Schottky junction accelerates and decelerates the diffusion of OH-/K+ions during the charging and discharging processes,respectively,to improve the pseudocapacitive behavior.The resulting pseudocapacitive negative electrodes exhibits a specific capacity of 2,114 C g^(-1)at 2 A g^(-1)matches almost that of the positive electrode’s 2,795 C g^(-1)at 3 A g^(-1).As a result,with the equivalent contribution from the positive and negative electrodes,an energy density of 236.1 Wh kg^(-1)is achieved at a power density of 921.9 W kg^(-1)with a total active mass of 15 mg cm-2.This strategy demonstrates the possibility of producing supercapacitors that adapt well to the supercapattery zone of a Ragone plot and that are equal to batteries in terms of energy density,thus,offering a route for further advances in electrochemical energy storage and conversion processes.展开更多
Silicon materials have attracted wide attention as negative materials due to exceptional gravimetric capacity and abundance. The strategy of using nano-silicon materials as structural units to construct nano/micro-str...Silicon materials have attracted wide attention as negative materials due to exceptional gravimetric capacity and abundance. The strategy of using nano-silicon materials as structural units to construct nano/micro-structured silicon-based negative materials for lithium-ion batteries has come into sight in recent years. In order to provide guidance for the material structure design of micro-sized silicon-based negative materials in practical application, in this work, two commercialized nano/micro-structured silicon-based negative materials with a specific capacity of about 650 mAh·g^(-1) were investigated and compared in the aspects of material microstructure, electrochemical performance of half cells, and electrode morphological evolution during cycling. The cycling performance(with capacity retention ratio of about 17% higher after 100 cycles) and electrode structure maintenance of the embedded structure Si/C material are superior to those of core–shell Si/C material. This research can provide guidance on design and application of nano/micro-structured silicon-based negative materials.展开更多
Silicon is very promising negative electrode materials for improving the energy density of lithium-ion batteries （LIBs） because of its high specific capacity, moderate potential, environmental friendliness, and low ...Silicon is very promising negative electrode materials for improving the energy density of lithium-ion batteries （LIBs） because of its high specific capacity, moderate potential, environmental friendliness, and low cost. However, the volume variation of Si negative electrodes is huge during lithiation/delithiation processes which results in pulverization, low cycling efficiency, and permanent capacity loss. In order to overcome this problem, tremendous efforts have been attempted. Among them the most successful strategy is to incorporate other components into silicon to form composite, especially the carbon medium. In this mini review, the recent progress on Si/C materials used as negative electrode of LIBs is summarized such as Si/amorphous carbon composite, Si/graphene composites, Si/carbon nanotubes or fibers composites. The fabrication, structure, electrochemical performances of different Si/C composites are discussed. In addition, some future directions are pointed out.展开更多
Rechargeable Al-ion batteries(AIBs)are considered as one of the most fascinating energy storage systems due to abundant Al resource and low cost.However,the cycling stability is subjected to critical problems for usin...Rechargeable Al-ion batteries(AIBs)are considered as one of the most fascinating energy storage systems due to abundant Al resource and low cost.However,the cycling stability is subjected to critical problems for using Al foil as negative electrode,including Al dendrites,corrosion and pulverization.For addressing these problems,here a lightweight self-supporting N-doped carbon rod array(NCRA)is demonstrated for a long-life negative electrode in AIBs.Experimental analysis and first-principle calculations reveal the storage mechanism involving the induced deposition of N-containing function groups to Al as well as the ideal skeleton of the NCRA matrix for Al plating/stripping,which is favorable for regulating Al nucleation and suppressing dendrites growth.Compared with the Al foil,the NCRA exhibits lower areal mass density(∼72%of Al foil),smaller thickness(40%of Al foil),but much longer cycle life(>4 times of Al foil).Benefiting from the remarkable stability of the array structure,symmetric cells show excellent cycling stability with small voltage hysteresis(∼80 mV)and meanwhile there are no corrosion and pulverization problems even after cycled for 120 hours.Besides,full cells also manifest long lifespan(1,500 cycles)and increased Coulombic efficiency(100±1%).展开更多
基金supported by the National Natural Science Foundation of China(No.22271101)the R&D Program of Guangzhou(2024A04J2497)+1 种基金the Key Laboratory of Polymer Chemistry&Physics of Ministry of Educationsupported by the High Performance Computing Platform of SCUT。
文摘High-entropy oxides(HEOs),offering reversible lithium storage and moderate operating potential,are considered promising negative electrodes.However,the intricate lithium storage mechanism within HE polycationic systems remains challenging.Here,we conduct comprehensive investigations into the electrochemical properties and structu ral evolution of(CrMnCoNiZn)_(3)O_(4)(HESO)to clarify lithium storage mechanisms.Density functional theory(DFT)calculations reveal that polycationic synergy modulates the electronic structure and d-band centers of HESO,delivering fast electrode kinetics.Exhaustive in-and exsitu analyses demonstrate that the residual crystalline phases acting as seed crystals maintain the spinel/rock-salt lattice persistence under the entropy stabilization effect,lattice distortion effect,and cation synergy,which guide cation crystallization upon the electric field to drive reversible lithium storage.Such properties underlie the HESO electrode with an exceptional rate and long-term capability.This work clarifies the roles of cationic synergy and seed-crystal-driven structural reversibility,providing a blueprint for designing high-performance HEO negative electrodes for next-generation lithium-ion batteries(LIBs).
基金supported by the National Natural Science Foundation of China(No.U2037601)the National Key Research and Development Program(No.2023YFB3809500)the Chongqing Technology Innovation and Application Development Project(No.CSTB2022TIAD-KPX0028).
文摘Rechargeable magnesium batteries(RMBs)have attracted much attention due to the high theoretical capacity(3833 mAh cm−3)of magnesium metal negative electrode and abundant resources.However,the preparation of ultra-thin magnesium foils faces the problems of rolling difficulty and high processing cost,while the use of thick magnesium foils leads to low utilization of magnesium and reduces the energy density.To tackle the above problems,we successfully prepared ultra-thin magnesium foils based on electrolytic process and investigated the effect of different substrates.The magnesium foils prepared using Mo substrate have more uniform surface morphology and lower surface roughness,which is attributed to the lower magnesium nucleation overpotential of Mo substrate.Meanwhile,density functional theory calculations show that the adsorption energy of Mo on Mg is more negative,which is conducive to achieving uniform nucleation and deposition of Mg.The Mg deposition on Mo substrate undergoes the characteristic stages of transient nucleation,nucleus accretion,multidirectional heterotopic growth,and columnar crystal stacking,and ultimately the formation of a dense deposited layer.In addition,the prepared ultra-thin Mg foil with Mo substrate can stably cycle for 1000 h at 3 mA cm^(-2) with high utilization of 50% in the symmetric cell.This study develops a facile method for the preparation of ultra-thin Mg foils,which opens up a new path for developing high-performance ultra-thin negative electrodes for RMBs.
基金supported by the National Natural Science Foundation of China(Nos.U22A20145,51904115,52072151,52171211,and 52271218)Jinan Independent Innovative Team(No.2020GXRC015)the Major Program of Shandong Province Natural Science Foundation(Nos.ZR2023ZD43 and ZR2021ZD05).
文摘The low specific capacitances(SCs)of traditional carbonaceous negative electrodes significantly limit the enhancement in energy density of aqueous hybrid supercapacitors(AHCs).It is still hugely challengeable to explore a candidate with large SCs,which can stably operate in the negative potential region mean-while.For this propose,we design and fabricate solid-solution Ru_(x)Cu_(1-x)O_(2) nanocrystals(NCs),which exhibit competitive SCs and electrochemical stability within the potential range from-0.9 V to 0.0 V in the aqueous KOH electrolyte.The incorporation of Cu enhances the electrochemical utilization of RuO_(2),reaction kinetics,electronic conductivity,and hydrogen evolution overpotentials,which are all highly dependent upon the added contents of Cu species.The optimized Ru_(0.8)Cu_(0.2)O_(2)(RuCu82)electrode of a high mass loading of 5 mg cm^(-2) reveals the best electrochemical capacitances in terms of reversible SCs and capacitance degradation at room temperature and-20℃.Furthermore,the reversible K^(+)-(de)intercalation induced pseudocapacitance is proposed for electrochemical charge storage process of RuCu82.In particu-lar,remarkable specific energy of 59.1 Wh kg-1 at 400 W kg-1 and excellent cycling stability are achieved in the assembled NiCoO_(2)//RuCu82 AHCs.Our contribution here presents a new promising negative elec-trode platform with high SCs and electrochemical stability for next-generation AHCs.
文摘Carbon materials,including graphite,hard carbon,soft carbon,graphene,and carbon nanotubes,are widely used as high-performance negative electrodes for sodium-ion and potassium-ion batteries(SIBs and PIBs).Compared with other materials,carbon materials are abundant,low-cost,and environmentally friendly,and have excellent electrochemical properties,which make them especially suitable for negative electrode materials of SIBs and PIBs.Compared with traditional carbon materials,modifications of the morphology and size of nanomaterials represent effective strategies to improve the quality of electrode materials.Different nanostructures make different contributions toward improving the electrochemical performance of electrode materials,so the synthesis of nanomaterials is promising for controlling the morphology and size of electrode materials.This paper reviews the progress made and challenges in the use of carbon materials as negative electrode materials for SIBs and PIBs in recent years.The differences in Na+and K+storage mechanisms among different types of carbon materials are emphasized.
基金This work was financially supported by the National Key Research and Development Program of China(No.2016YFB0301305)the Talent Plan Project of Beijing(No.2018000097607G378)the National Natural Science Foundation of China(U166420031).
文摘Nano-silicon(nano-Si)and its composites have been regarded as the most promising negative electrode materials for producing the next-generation Li-ion batteries(LIBs),due to their ultrahigh theoretical capacity.However,the commercial applications of nano Si-based negative electrode materials are constrained by the low cycling stability and high costs.The molten salt electrolysis of SiO_(2)is proven to be suitable to produce nano-Si with the advantages of in-situ microstructure control possibilities,cheap affordability and scale-up process capability.Therefore,an economical approach for electrolysis,with a SiO_(2)/graphite porous electrode as cathode,is adopted to produce nano-Si/graphite composite negative electrode materials(SGNM)in this study.The electrolytic product of the optimized porous electrode is taken as the negative electrode materials for LIBs,and it offers a capacity of 733.2 mAh·g^(-1)and an initial coulombic efficiency of 86.8%in a coin-type cell.Moreover,the capacity of the SGNM retained 74.1%of the initial discharging capacity after 50 cycles at 0.2C,which is significantly higher than that of the simple mixture of silicon and graphite obtained from the formation of silicon carbide(SiC)between nano-Si and graphite particles.Notably,this new approach can be applied to a large-scale production.
基金financial support from the National Natural Science Foundation of China(Nos.21576034 and 51908092)the State Education Ministry and Fundamental Research Funds for the Central Universities(Nos.2019CDQYCL042,2019CDXYCL0031,2018CDYJSY0055,106112017CDJQJ138802,106112017CDJSK04XK11 and 106112017CDJXSYY0001)the Joint Funds of the National Natural Science Foundation of China-Guangdong(No.U1801254)。
文摘The complex-architectured NiFe-LDH@FeOOH negative material was first prepared by simple two-step hydrothermal method.In this study,the porous nanostructure of FeOOH nanosheets features a large number of accessible channels to electroactive sites and the two-dimensional layered structure of NiFe-LDH nanosheets have an open spatial structure with high specific surface area,which enhance the diffusion of ions in the active material.Benefited from above advantages,the excellent electrochemical properties were demonstrated.NiFe-LDH@FeOOH nanocomposites present high specific capacitance(1195 F/g at a current density of 1 A/g),lower resistance and well cycling performance(90.36% retention after 1000 cycles).Furthermore,the NiFe-LDH@MnO2//NiFe-LDH@FeOOH supercapacitor exhibits22.68 Wh/kg energy density at 750 W/kg power density,demonstrating potential application in energy storage devices.
基金supported by the Agence Nationale de la Recherche(ANR)of France[grant ANR-16-CE05-0004]。
文摘A composite In-Pb:carbon was successfully synthetized by a two-step mechanochemical synthesis in order to obtain an adequate particles size and structure to investigate the electrochemical reactivity of the In-Pb solid solution towards Mg.A potential synergetic coupling of electroactive elements In and Pb was examined using electrochemical and ex situ X-ray diffraction analyses.The potential profile of the solid solution indicates the formation of Mg_(2)Pb and Mg In.However,the diffraction study suggests a peculiar electrochemically-driven amorphization of Mg In during the magnesiation,in strong contrast to Mg In crystallization in In-based and In Bi-based electrodes reported in the literature.Combining In and Pb favors the amorphization of Mg In and a high first magnesiation capacity of about 550 m Ah g^(-1),but is thereafter detrimental to the material’s reversibility.These results emphasize the possible influence of electrochemically-driven amorphization and crystallization processes on electrochemical performance of battery materials.
基金supported by the National Natural Science Foundation of China,China(No.21975101)Science and Technology Innovation Team Project of Jilin University,China(No.2017TD31)Major Science and Technology Research Project of “Shuangshi Project”in Changchun City,China(No.17SS018)。
文摘Lead-carbon hybrid capacitors are the electrochemical devices between supercapacitors and lead-acid batteries,with low prices,stability in high and low temperature,good security and broad application prospects.This paper introduces an electrodeposition behavior of Pb^(2+)on the negative electrode,which can improve the cycle life of the lead-carbon hybrid capacitor.During the charging process,lead ions in the electrolyte can diffuse from the positive electrode of the lead-carbon hybrid capacitor into the negative electrode.When charging at a low current density,the lead ions around the negative electrode can be reduced to lead,and it is then quickly converted to lead sulfate crystals.With the increase of the number of cycles,the final result is sulfation.Sulfation can reduce the specific surface area of the electric double layer,thereby reducing the capacitance performance of the carbon material.As a result,it reduces the charge-discharge efficiency of the lead-carbon hybrid capacitor.The service life of lead-carbon hybrid capacitor is significantly improved by the inhibition of lead deposition by anion exchange membrane.The capacity retention rate at 5 A/g is improved from 84%after 1000 cycles to 95%after 10,000 cycles.The discovery of lead deposition in the negative electrode is conducive to improving the performance of long-life lead-carbon hybrid capacitors.
基金financially supported by the National Natural Science Foundation of China(No.51874019)。
文摘Metal aluminum batteries(MABs)are considered potential large-scale energy storage devices because of their high energy density,resource abundance,low cost,safety,and environmental friendliness.Given their high electrical conductivity,high theoretical specific capacity,and high discharge potential,Te is considered a potential positive electrode material for MABs.Nonetheless,the critical issues induced by the chemical and electrochemical dissolution of tellurium and subsequent chemical precipitation on bare Al negative electrodes result in poor cycle stability and low discharge capacity of Al-Te batteries.Here an efficient TiB_(2)-based modified layer has been proposed to address bare Al electrodes(Al/TB).Consequently,the low-voltage hysteresis and long cycle life of the Al/TB negative electrode have been achieved.In addition,the electrochemical performance of the Al-Te battery based on the Al/TB negative electrode is dramatically improved.Furthermore,the modified separator technology is introduced to match with the as-designed Al/TB negative electrode.Therefore,the record-setting long-term cycle stability of up to 500 cycles has been achieved in the Al-Te battery.The facile strategy also opens a potential route for other high-energy density battery systems,such as Al-S and Al-Se batteries.
基金partially supported by Advanced Low Carbon Technology Research and Development Program(ALCA,16200610802)Joint Usage/Research Program on Zero-Emission Energy Research,Institute for Applied Ecology,Kyoto University(ZE29A-14,ZE30A-05,ZE30A-06)+1 种基金Japan Society for the Promotion of Science(JSPS)KAKENHI(Grant Number 17H03128,17K17888,16K05954)supported by "Advanced Characterization Nanotechnology Platform,Nanotechnology Platform Program of the Ministry of Education,Culture,Sports,Science and Technology(MEXT),Japan" at the Research Center for Ultra-High Voltage Electron Microscopy in Osaka University(A-17-OS-0020,A-18-S-0002)
文摘The degradation mechanism of an Sn_4P_3 electrode as Na-ion battery anode was investigated by using a transmission electron microscopic observation. At the first desodiation, we confirmed that Sn nanoparticles with 6 nm in size were dispersed in an amorphous-like P matrix.Compared to this, we observed aggregated Sn particles with sizes exceeding 50 nm after the drastic capacity fading. The capacity fading mechanism was for the first time confirmed to be Sn aggregation. To improve the capacity decay, we carried out the two kinds of chargeàdischarge cycling tests under the reduced volume changes of Sn particles and P matrix by limiting desodiation reactions of Nae Sn and Na3P, respectively. The Sn_4P_3 electrode exhibited an excellent cyclability with the discharge capacity of 500 mA hg^(-1) for 420 cycles under the limited desodiation, whereas the capacity decay was accelerated under the limited sodiation. The results suggest that the Sn aggregation can be improved by the reduced volume change of the P matrix, and that it is very effective for improving anode performance of Sn_4P_3 electrode.
基金financially supported by the Research Program from Korea Institute of Industrial Technology(EM220011)the Technology Innovation Program(20020229,Development of technology for manufacturing catalysts and electrode parts by use of low contents precious metals of rare metals) funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea)+2 种基金the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT)(2022R1F1A1072569)supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science,ICT & Future Planning(NRF2020R1C1C1010493)“Regional Innovation Strategy(RIS)” through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(MOE)(2021RIS-004)。
文摘Development of electrodes with high electrocatalytic activity and stability is essential for solving problems that still restrict the extensive application of vanadium redox flow batteries(VRFBs).Here,we designed a novel negative electrode with superior electrocatalytic activity by tailoring nitrogen functional groups,such as newly formed nitro and pyridinic-N transformed to pyridonic-N,from the prenitrogen-doped electrode.It was experimentally confirmed that an electrode with pyridonic-N and nitro fuctional groups(tailored nitrogen-doped graphite felt,TNGF) has superior electrocatalytic acivity with enhanced electron and mass transfer.Density functional theory calulations demonstrated the pyridonic-N and nitro functional groups promoted the adsorption,charge transfer,and bond formation with the vanadium species,which is consistent with expermental results.In addition,the V2+/V3+redox reaction mechanism on pyridonic-N and nitro functional groups was estabilised based on density functional theory(DFT) results.When TNGF was applied to a VRFB,it enabled enhanced-electrolyte utilization and energy efficiencies(EE) of 57.9% and 64.6%,respectively,at a current density of 250 mA cm^(-2).These results are 18.6% and 8.9% higher than those of VRFB with electrode containing graphitic-N and pyridinicN groups.Interestingly,TNGF-based VRFB still operated with an EE of 59% at a high current density of300 mA cm^(-2).The TNGF-based VRFB exhibited stable cycling performance without noticeable decay of EE over 450 charge-discharge cycles at a current density of 250 mA cm^(-2).The results of this study suggest that introducing pyridonic-N and nitro groups on the electrode is effective for improving the electrochemical performance of VRFBs.
基金supported by the Australia-India Strategic Research Fund(AISRF,ST060048)
文摘Nanoporous anatase TiO_2 （np-TiO_2） electrodes have been developed via the anodization of titanium foils in fluoride containing electrolytes, and its application in rechargeable lithium-ion batteries （LIBs） was investigated. Four different types of np-TiO_2 electrodes with different pore diameters of 14.7±8.2 nm, 12.85±6.8 nm, 11.0±5.5, and 26.7±13.6 nm were fabricated for evaluating the effect of nanoporous characteristics on the LIB performance. The discharge capacity of the four battery types 1, 2, 3, and 4 were 132.7 mAh·g^-1, 316.7 mAh·g^-1, 154.3 mAh·g^-1, and 228.4 mAh·g^-1, respectively. In addition, these electrodes 1, 2, 3, and 4 exhibited reversible capacity of 106.9 mAh·g^-1 after 295th, 180.9 mAh·g^-1 after 220th, 126.1 mAh·g^-1 after 150th, and 206.7 mAh·g^-1 after 85th cycle at a rate of 1 C, respectively. It was noted that the cyclic life of the batteries had an inverse relationship, and the capacity had a proportional relationship to the pore diameter. The enhanced electrochemical performance of the nanoporous electrodes can be attributed to the improved conductivity and the enhanced kinetics of lithium insertion/extraction at electrode/electrolyte interfaces because of the large specific surface area of np-TiO_2 electrodes.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11374195 and 11405098)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2013FM006)
文摘The electronic transport properties of a single thiolated arylethynylene molecule with 9,10-dihydroanthracene core, denoted as TADHA, is studied by using non-equilibrium Green＇s function formalism combined with ab initio calculations. The numerical results show that the TADHA molecule exhibits excellent negative differential conductance （NDC） behavior at lower bias regime as probed experimentally. The NDC behavior of TADHA molecule originates from the Stark effect of the applied bias voltage, by which the highest occupied molecular orbital （HOMO） and the HOMO-1 are pulled apart and become localized. The NDC behavior of TADHA molecular system is tunable by changing the electrode distance. Shortening the electrode separation can enhance the NDC effect which is attributed to the possible increase of coupling between the two branches of TADHA molecule.
基金Project(NCET-10-0946)supported by Program for New Century Excellent Talents in University of ChinaProject(2017JY0038)supported by Science and Technology Key Project of Sichuan Province,ChinaProject(2013TX8)supported by Titanium and Titanium Alloy Innovation Team of Panzhihua City,China
文摘Anodic oxidation with different electrolyte was employed to improve the electrochemical properties of carbon paper as negative electrode for vanadium redox battery(VRB).The treated carbon paper exhibits enhanced electrochemical activity for V^2+/V^3+redox reaction.The sample(CP-NH3)treated in NH3 solution demonstrates superior performance in comparison with the sample(CP-NaOH)treated in NaOH solution.X-ray photoelectron spectroscopy results show that oxygen-and nitrogen-containing functional groups have been introduced on CP-NH3 surface by the treatment,and Raman spectra confirm the increased surface defect of CP-NH3.Energy storage performance of cell was evaluated by charge/discharge measurement by using CP-NH3.Usage of CP-NH3 can greatly improve the cell performance with energy efficiency increase of 4.8%at 60 mA/cm^2.The excellent performance of CP-NH3 mainly results from introduction of functional groups as active sites and improved wetting properties.This work reveals that anodic oxidation is a clean,simple,and efficient method for boosting the performance of carbon paper as negative electrode for VRB.
基金Project supported by National Natural Science Foundation of China(51207089)Shang-hai Maritime University(20120097).
文摘Many sub-products of pulsed discharge,such as ultraviolet light,strong electric fields,shock waves and active species,are effective in treating wastewater.To improve the efficiency of the discharge plasma technology in removing pollutants,adding TiO2 photo-catalyst to pulsed discharges could help.A negative-pulsed-discharge system,which has nozzle discharge electrodes with or without TiO2 coating,is used to degrade azo dye Acid OrangeⅡ,and the effects of several key conditions(maximum pulse voltage,pulse repetition frequency,initial mass concentration of Acid OrangeⅡinitial solution pH,treatment duration,the phase of discharge,and the existence of TiO2)on the degradation are experimentally investigated.The degradation of Acid OrangeⅡincreases with maximum pulse voltage,pulse repetition frequency,and treatment duration,and it is larger when putting the discharge electrode on the solution surface than in air or inside the solution,i.e.the discharge in gas phase is more effective than that in gas-liquid phase or liquid phase.The degradation decreases as the initial mass concentration of the solution increases.It also relates to pH and is higher at acidic conditions than at neutral or alkaline conditions.Compared to treatments without TiO2,the ones using the nozzle discharge electrode with TiO2 coated increase the degradation of Acid OrangeⅡby 5%.It is concluded that the proposed system with TiO2 added in can remove Acid OrangeⅡfrom wastewater effectively.
基金supported by National Natural Science Foundation of China(Grant No.51207089)
文摘The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods.The nozzle-cylinder electrode in the discharge reactor was supplied witha negative nanosecond pulsed generator.The optical emission spectrum diagnosis revealed that OH（A2∑＋ → X2Π,306–309 nm）,N32（CΠ→B3Πg,337 nm）,O（3p5p→3s-5s-0,777.2 nm）and O（3p3p→3s3s0,844.6 nm）were produced in the discharge plasma channels.The electron temperature（Te）was calculated from the emission relative intensity ratio between the atomic O 777.2 nm and 844.6 nm,and it increased with the applied voltage and the pulsed frequency and fell within the range of 0.5–0.8 e V.The gas temperature（Tg）that was measured by Lifbase was in a range from 400 K to 600 K.
基金financially supported by the National Research Foundation of Korea(NRF-2022R1A2C2010803)。
文摘Pseudo-capacitive negative electrodes remain a major bottleneck in the development of supercapacitor devices with high energy density because the electric double-layer capacitance of the negative electrodes does not match the pseudocapacitance of the corresponding positive electrodes.In the present study,a strategically improved Ni-Co-Mo sulfide is demonstrated to be a promising candidate for high energy density supercapattery devices due to its sustained pseudocapacitive charge storage mechanism.The pseudocapacitive behavior is enhanced when operating under a high current through the addition of a classical Schottky junction next to the electrode-electrolyte interface using atomic layer deposition.The Schottky junction accelerates and decelerates the diffusion of OH-/K+ions during the charging and discharging processes,respectively,to improve the pseudocapacitive behavior.The resulting pseudocapacitive negative electrodes exhibits a specific capacity of 2,114 C g^(-1)at 2 A g^(-1)matches almost that of the positive electrode’s 2,795 C g^(-1)at 3 A g^(-1).As a result,with the equivalent contribution from the positive and negative electrodes,an energy density of 236.1 Wh kg^(-1)is achieved at a power density of 921.9 W kg^(-1)with a total active mass of 15 mg cm-2.This strategy demonstrates the possibility of producing supercapacitors that adapt well to the supercapattery zone of a Ragone plot and that are equal to batteries in terms of energy density,thus,offering a route for further advances in electrochemical energy storage and conversion processes.
基金financially supported by the National Key R&D Program of China(No.2016YFB0100400)the National Natural Science Foundation of China(Nos.51504032,51604032 and U1664256)。
文摘Silicon materials have attracted wide attention as negative materials due to exceptional gravimetric capacity and abundance. The strategy of using nano-silicon materials as structural units to construct nano/micro-structured silicon-based negative materials for lithium-ion batteries has come into sight in recent years. In order to provide guidance for the material structure design of micro-sized silicon-based negative materials in practical application, in this work, two commercialized nano/micro-structured silicon-based negative materials with a specific capacity of about 650 mAh·g^(-1) were investigated and compared in the aspects of material microstructure, electrochemical performance of half cells, and electrode morphological evolution during cycling. The cycling performance(with capacity retention ratio of about 17% higher after 100 cycles) and electrode structure maintenance of the embedded structure Si/C material are superior to those of core–shell Si/C material. This research can provide guidance on design and application of nano/micro-structured silicon-based negative materials.
基金This work was supported by the Natural Distin- guished Youth Scientists Project of China （No. 51425301）, the National Natural Science Foundation of China （No. 51673096） and the Natural Science Founda- tion of Jiangsu Province （No. BK20151534）, and Open Foundation of Jiangsu Key Laboratory of Engineering Mechanics in Southeast University （LEM 16B03）.
文摘Silicon is very promising negative electrode materials for improving the energy density of lithium-ion batteries （LIBs） because of its high specific capacity, moderate potential, environmental friendliness, and low cost. However, the volume variation of Si negative electrodes is huge during lithiation/delithiation processes which results in pulverization, low cycling efficiency, and permanent capacity loss. In order to overcome this problem, tremendous efforts have been attempted. Among them the most successful strategy is to incorporate other components into silicon to form composite, especially the carbon medium. In this mini review, the recent progress on Si/C materials used as negative electrode of LIBs is summarized such as Si/amorphous carbon composite, Si/graphene composites, Si/carbon nanotubes or fibers composites. The fabrication, structure, electrochemical performances of different Si/C composites are discussed. In addition, some future directions are pointed out.
基金We acknowledge financial support from the National Natural Science Foundation of China(Nos.51725401 and 51874019)the Fundamental Research Funds for the Central Universities(No.FRF-TP-17-002C2).
文摘Rechargeable Al-ion batteries(AIBs)are considered as one of the most fascinating energy storage systems due to abundant Al resource and low cost.However,the cycling stability is subjected to critical problems for using Al foil as negative electrode,including Al dendrites,corrosion and pulverization.For addressing these problems,here a lightweight self-supporting N-doped carbon rod array(NCRA)is demonstrated for a long-life negative electrode in AIBs.Experimental analysis and first-principle calculations reveal the storage mechanism involving the induced deposition of N-containing function groups to Al as well as the ideal skeleton of the NCRA matrix for Al plating/stripping,which is favorable for regulating Al nucleation and suppressing dendrites growth.Compared with the Al foil,the NCRA exhibits lower areal mass density(∼72%of Al foil),smaller thickness(40%of Al foil),but much longer cycle life(>4 times of Al foil).Benefiting from the remarkable stability of the array structure,symmetric cells show excellent cycling stability with small voltage hysteresis(∼80 mV)and meanwhile there are no corrosion and pulverization problems even after cycled for 120 hours.Besides,full cells also manifest long lifespan(1,500 cycles)and increased Coulombic efficiency(100±1%).
