A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and...A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and Mo2S3 nanoparticles were integrated at the edges of Co3O4 nanosheets,creating a rich,heterogeneous interface that enhances the synergistic effects of each component.In an alkaline electrolyte,the synthesized CoMoNiO-S/NF-110 exhibited superior electrocatalytic performance for oxygen evolution reaction(OER),achieving current densities of 100 and 200 mA·cm^(-2) with low overpotentials of 199.4 and 224.4 mV,respectively,outperforming RuO2 and several high-performance Mo and Ni-based catalysts.This excellent performance is attributed to the rich interface formed between the components and active sites exposed by the defect structure.展开更多
The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecul...The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276.展开更多
Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a fo...Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies.展开更多
Lithium-oxygen(Li-O2)batteries are perceived as a promising breakthrough in sustainable electrochemical energy storage,utilizing ambient air as an energy source,eliminating the need for costly cathode materials,and of...Lithium-oxygen(Li-O2)batteries are perceived as a promising breakthrough in sustainable electrochemical energy storage,utilizing ambient air as an energy source,eliminating the need for costly cathode materials,and offering the highest theoretical energy density(~3.5 k Wh kg^(-1))among discussed candidates.Contributing to the poor cycle life of currently reported Li-O_(2)cells is singlet oxygen(1O_(2))formation,inducing parasitic reactions,degrading key components,and severely deteriorating cell performance.Here,we harness the chirality-induced spin selectivity effect of chiral cobalt oxide nanosheets(Co_(3)O_(4)NSs)as cathode materials to suppress 1O_(2)in Li-O_(2)batteries for the first time.Operando photoluminescence spectroscopy reveals a 3.7-fold and 3.23-fold reduction in 1O_(2)during discharge and charge,respectively,compared to conventional carbon paperbased cells,consistent with differential electrochemical mass spectrometry results,which indicate a near-theoretical charge-to-O_(2)ratio(2.04 e-/O_(2)).Density functional theory calculations demonstrate that chirality induces a peak shift near the Fermi level,enhancing Co 3d-O 2p hybridization,stabilizing reaction intermediates,and lowering activation barriers for Li_(2)O_(2)formation and decomposition.These findings establish a new strategy for improving the stability and energy efficiency of sustainable Li-O_(2)batteries,abridging the current gap to commercialization.展开更多
The development of Pt-free catalysts for the oxygen reduction reaction(ORR)is a great issue for meeting the cost challenges of proton exchange membrane fuel cells(PEMFCs)in commercial applications.In this work,a serie...The development of Pt-free catalysts for the oxygen reduction reaction(ORR)is a great issue for meeting the cost challenges of proton exchange membrane fuel cells(PEMFCs)in commercial applications.In this work,a series of RuCo/C catalysts were synthesized by NaBH4 reduction method under the premise that the total metal mass percentage was 20%.X-ray diffraction(XRD)patterns and scanning electron microscopy(SEM)confirmed the formation of single-phase nanoparticles with an average size of 33 nm.Cyclic voltammograms(CV)and linear sweep voltammograms(LSV)tests indicated that RuCo(2:1)/C catalyst had the optimal ORR properties.Additionally,the RuCo(2:1)/C catalyst remarkably sustained 98.1% of its activity even after 3000 cycles,surpassing the performance of Pt/C(84.8%).Analysis of the elemental state of the catalyst surface after cycling using X-ray photoelectron spectroscopy(XPS)revealed that the Ru^(0) percentage of RuCo(2:1)/C decreased by 2.2%(from 66.3% to 64.1%),while the Pt^(0) percentage of Pt/C decreased by 7.1%(from 53.3% to 46.2%).It is suggested that the synergy between Ru and Co holds the potential to pave the way for future low-cost and highly stable ORR catalysts,offering significant promise in the context of PEMFCs.展开更多
Heteroatom-doped carbon is considered a promising alternative to commercial Pt/C as an efficient catalyst for the oxygen reduction reaction(ORR).This study presents the synthesis of iron-loaded,sulfur and nitrogen co-...Heteroatom-doped carbon is considered a promising alternative to commercial Pt/C as an efficient catalyst for the oxygen reduction reaction(ORR).This study presents the synthesis of iron-loaded,sulfur and nitrogen co-doped carbon(Fe/SNC)via in situ incorporation of 2-aminothiazole molecules into zeolitic imidazolate framework-8(ZIF-8)through coordination between metal ions and organic ligands.Sulfur and nitrogen doping in carbon supports effectively modulates the electronic structure of the catalyst,increases the Brunauer-Emmett-Teller surface area,and exposes more Fe-N_(x)active centers.Fe-loaded,S and N co-doped carbon with Fe/S molar ratio of 1:10(Fe/SNC-10)exhibits a half-wave potential of 0.902 V vs.RHE.After 5000 cycles of cyclic voltammetry,its half-wave potential decreases by only 20 mV vs.RHE,indicating excellent stability.Due to sulfur s lower electronegativity,the electronic structure of the Fe-N_(x)active center is modulated.Additionally,the larger atomic radius of sulfur introduces defects into the carbon support.As a result,Fe/SNC-10 demonstrates superior ORR activity and stability in alkaline solution compared with Fe-loaded N-doped carbon(Fe/NC).Furthermore,the zinc-air battery assembled with the Fe/SNC-10 catalyst shows enhanced performance relative to those assembled with Fe/NC and Pt/C catalysts.This work offers a novel design strategy for advanced energy storage and conversion applications.展开更多
Seawater zinc-air batteries are promising energy storage devices due to their high energy density and utilization of seawater electrolytes.However,their efficiency is hindered by the sluggish oxygen reduction reaction...Seawater zinc-air batteries are promising energy storage devices due to their high energy density and utilization of seawater electrolytes.However,their efficiency is hindered by the sluggish oxygen reduction reaction(ORR)and chlorideinduced degradation over conventional catalysts.In this study,we proposed a universal synthetic strategy to construct heteroatom axially coordinated Fe–N_(4) single-atom seawater catalyst materials(Cl–Fe–N_(4) and S–Fe–N_(4)).X-ray absorption spectroscopy confirmed their five-coordinated square pyramidal structure.Systematic evaluation of catalytic activities revealed that compared with S–Fe–N_(4),Cl–Fe–N_(4) exhibits smaller electrochemical active surface area and specific surface area,yet demonstrates higher limiting current density(5.8 mA cm^(−2)).The assembled zinc-air batteries using Cl–Fe–N_(4) showed superior power density(187.7 mW cm^(−2) at 245.1 mA cm^(−2)),indicating that Cl axial coordination more effectively enhances the intrinsic ORR activity.Moreover,Cl–Fe–N_(4) demonstrates stronger Cl−poisoning resistance in seawater environments.Chronoamperometry tests and zinc-air battery cycling performance evaluations confirmed its enhanced stability.Density functional theory calculations revealed that the introduction of heteroatoms in the axial direction regulates the electron center of Fe single atom,leading to more active reaction intermediates and increased electron density of Fe single sites,thereby enhancing the reduction in adsorbed intermediates and hence the overall ORR catalytic activity.展开更多
Carbon-based air cathodes offer low cost,high electrical conductivity,and structural tunability.However,they suffer from limited catalytic activity and inefficient gas transport,and they typically rely on noble metal ...Carbon-based air cathodes offer low cost,high electrical conductivity,and structural tunability.However,they suffer from limited catalytic activity and inefficient gas transport,and they typically rely on noble metal additives or complex multilayer configurations.To tackle these issues,this study devised a self-activated integrated carbon-based air cathode.By integrating in situ catalytic site construction with structural optimization,the strategy not only induces the formation of oxygen functional groups(─C─OH,─C═O,─COOH),hierarchical pores,and uniformly distributed active sites,but also establishes a favorable electronic and mass-transport environment.Furthermore,the roll-pressing-based integrated design streamlines electrode construction,reinforces interfacial bonding,and significantly enhances mechanical stability.Density functional theory(DFT)calculations show that oxygen functional groups initiate hydrogen bonding interaction and promote charge enrichment,which improves the activity of the cathode and facilitates intermediate adsorption/desorption in oxygen reduction and evolution reactions processes.As a result,the integrated air cathode-based rechargeable zinc-air batteries(RZABs)achieve a high specific capacity of 811 mAh g^(-1).It also performs well in quasi-solid-state RZABs and silicon-air batteries systems across a wide temperature range,demonstrating strong adaptability and application potential.This study provides a scalable and cost-effective design strategy for high-performance carbon-based air cathodes,offering new insights into advancing durable and practical metal-air energy systems.展开更多
Oxygen evolution reaction(OER)is a key step in hydrogen production by water electrolysis technology.How-ever,developing efficient,stable,and low-cost OER electrocatalysts is still challenging.This article presents the...Oxygen evolution reaction(OER)is a key step in hydrogen production by water electrolysis technology.How-ever,developing efficient,stable,and low-cost OER electrocatalysts is still challenging.This article presents the preparation of a series of novel copper iridium nanocatalysts with heterostructures and low iridium content for OER.The electrochemical tests revealed higher OER of Cu@Ir_(0.3) catalyst under acidic conditions with a generated current density of 10 mA/cm^(2) at only 284 mV overpotential.The corresponding OER mass activity was estimated to be 1.057 A/mgIr,a value 8.39-fold higher than that of the commercial IrO_(2).After 50 h of endurance testing,the Cu@Ir_(0.3) catalyst preserved excellent catalytic activity with a negligible rise in overpotential and maintained a good heterostructures.Cu@Ir_(0.3) The excellent OER activity can be attributed to its heterostructure,as con-firmed by density functional theory(DFT)calculations,indicating that Cu@Ir The coupling between isoquanta causes charge redistribution,optimizing the adsorption energy of unsaturated Ir sites for oxygen intermediates and reducing the energy barrier of OER free energy determining the rate step.In summary,this method provides a new approach for designing efficient,stable,and low iridium content OER catalysts.展开更多
4-Nitrophenol(4-NP),a toxic and persistent pollutant in chemical wastewater,presents significant challenges in degradation and mineralization.Conventional ozone oxidation catalysts are hindered by low efficiency,mass ...4-Nitrophenol(4-NP),a toxic and persistent pollutant in chemical wastewater,presents significant challenges in degradation and mineralization.Conventional ozone oxidation catalysts are hindered by low efficiency,mass transfer constraints and metal leaching,necessitating the development of stable and efficient catalysts.Herein,BCn-H/MS,the derivative of Bi(Ce)-MOF,was prepared by in situ incorporation,thermal decomposition and acid etching.The resulting materials were characterized and employed in catalytic ozonation for the reduction of 4-NP.Under the specific experimental conditions of the O_(3)+BC0.3-H/MS system,the total organic carbon(TOC)and chemical oxygen demand(COD)removal rates of 4-NP were observed to reach 94.6%and 91.8%within 30 min,respectively.These two parameters were improved by raising the initial pH,reducing the pollutant concentration and increasing the catalyst dosage.The abundant oxygen vacancies(OVs)were regarded as the pivotal catalytic site of BC0.3-H/MS,which was conducive to the adsorption of O_(3) and the acceleration of the formation of reactive oxygen species(ROS).The regular hollow square structure effectively boosted the specific surface area,increased OVs exposure and accelerated the adsorption and mass transfer process.The electron paramagnetic resonance(EPR)results demonstrated that the primary ROS engaged in the degradation reaction were⋅OH and⋅O_(2)−.BC0.3-H/MS demonstrated excellent stability and reusability in cyclic experiments.Toxicity analysis revealed that the O_(3)+BC0.3-H/MS system exhibited an effective detoxification effect.Ultimately,the primary degradation pathway of 4-NP was proposed through liquid chromatography-mass spectroscopy(LC-MS)and in-situ diffuse reflectance infrared fourier-transform spectroscopy(DRIFTS)analyses at varying reaction times.展开更多
Abiotic oxygen formation predates photosynthesis,sustaining early chemical evolution,yet its elementary mechanisms remain contested.Here,we show the production pathways for molecular oxygen from doubly ionized carbon ...Abiotic oxygen formation predates photosynthesis,sustaining early chemical evolution,yet its elementary mechanisms remain contested.Here,we show the production pathways for molecular oxygen from doubly ionized carbon dioxide upon electron-impact.Through fragment ions and electron coincidence momentum imaging,we unambiguously determine the ionization mechanism by measuring the projectile energy loss in association with the C^(+) +O_(2)^(+) channel.Further potential energy and trajectory calculations enable us to elucidate the dynamical details of this fragmentation process,in which a bond rearrangement pathway is found to proceed via the structural deformation to a triangular intermediate.Moreover,we demonstrate a further roaming pathway for the formation of O_(2)^(+) from CO_(2)^(+) 2,in which a frustrated C-O bond cleavage leaves the O atom without sufficient energy to escape.The O atom then wanders around varied configuration spaces of the flat potential energy regions and forms a C-O-O_(2)^(+) intermediate prior to the final products C^(+) +O_(2)^(+).Considering the large quantities of free electrons in interstellar space,the processes revealed here are expected to be significant and should be incorporated into atmospheric evolution models.展开更多
The key to realize long-life high energy density lithium batteries is to exploit functional electrolytes capable of stabilizing both high voltage cathode and lithium anode.The emergence of localized high-concentration...The key to realize long-life high energy density lithium batteries is to exploit functional electrolytes capable of stabilizing both high voltage cathode and lithium anode.The emergence of localized high-concentration electrolytes(LHCEs)shows great promise for ameliorating the above-mentioned interfacial issues.In this work,a lithium difluoro(oxalate)borate(LiDFOB)based nonflammable dual-anion LHCE is designed and prepared.Dissolving in the mixture of trimethyl phosphate(TMP)/1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropylether(D_(2)),the continuously consumption of LiDFOB is suppressed by simply introducing lithium nitrate(LiNO_(3)).Meantime,as most of the TMP molecular are coordinated with Li^(+),the electrolyte does not show incompatibility issue between neither metal lithium nor graphite anode.Therefore,it demonstrates excellent capability in stabilizing the interface of Ni-rich cathode and regulating lithium deposition morphology.The Li||LiNi_(0.87)Co_(0.08)Mn_(0.05)O_(2)(NCM87)batteries exhibit high capacity retention of more than 90%after 200 cycles even under the high cutoff voltage of 4.5 V,1 C rate.This study offers a prospective method to develop safe electrolytes suitable for high voltage applications,thus providing higher energy densities.展开更多
By optimizing electrolyte formulation to inhibit the deposition of transition metal ions(TMIs) on the surface of the graphite anode is an effective way to improve the electrochemical performance of lithium-ion batteri...By optimizing electrolyte formulation to inhibit the deposition of transition metal ions(TMIs) on the surface of the graphite anode is an effective way to improve the electrochemical performance of lithium-ion batteries.At present,it is generally believed the formation of an effective interfacial film on the surface of the anode electrode is the leading factor in reducing the dissolution of TMIs and prevent TMIs from being embedded in the electrode.It ignores the influence of the solvation structures in the electrolyte system with different composition,and is not conducive to the design of the electrolyte formulation from the perspective of changing the concentration and the preferred solvent to inhibit the degradation of battery performance caused by TMIs deposition.In this work,by analyzing the special solvation structures of the high-concentra tion electrolyte,we study the main reason why high-concentration electrolyte inhibits the destructive effect of Mn(Ⅱ) on the electrochemical performance of LIBs.By combining the potentialresolved in-situ electrochemical impedance spectroscopy technology(PRIs-EIS) and density functional theory(DFT) calculation,we find that Mn(Ⅱ) mainly exists in the form of contact ions pairs(CIPs) and aggregates(AGGs) in high-concentration electrolyte.These solvation structures can reduce the destructive effect of Mn(Ⅱ) on battery performance from two aspects:on the one hand,it can rise the lowest unoccupied orbital(LUMO) value of the solvation structures of Mn(Ⅱ),thereby reducing the chance of its reduction;on the other hand,the decrease of Mn2+ions reduction can reduce the deposition of metallic manganese in the solid electrolyte interphase(SEI),thereby avoiding the continuous growth of the SEI.This study can be provided inspiration for the design of electrolytes to inhibit the destructive effect of TMls on LIBs.展开更多
The commercialization of silicon-based anodes is affected by their low initial Coulombic efficiency(ICE)and capacity decay,which are attributed to the formation of an unstable solid electrolyte interface(SEI)layer.Her...The commercialization of silicon-based anodes is affected by their low initial Coulombic efficiency(ICE)and capacity decay,which are attributed to the formation of an unstable solid electrolyte interface(SEI)layer.Herein,a feasible and cost-effective prelithiation method under a localized highconcentration electrolyte system(LHCE)for the silicon-silica/graphite(Si-SiO_(2)/C@G)anode is designed for stabilizing the SEI layer and enhancing the ICE.The thin SiO_(2)/C layers with-NH_(2) groups covered on nano-Si surfaces are demonstrated to be beneficial to the prelithiation process by density functional theory calculations and electrochemical performance.The SEI formed under LHCE is proven to be rich in ionic conductivity,inorganic substances,and flexible organic products.Thus,faster Li+transportation across the SEI further enhances the prelithiation effect and the rate performance of Si-SiO_(2)/C@G anodes.LHCE also leads to uniform decomposition and high stability of the SEI with abundant organic components.As a result,the prepared anode shows a high reversible specific capacity of 937.5 mAh g^(-1)after 400 cycles at a current density of 1 C.NCM 811‖Li-SSGLHCE full cell achieves a high-capacity retention of 126.15 mAh g^(-1)at 1 C over 750 cycles with 84.82%ICE,indicating the great value of this strategy for Si-based anodes in large-scale applications.展开更多
The resourceful and inexpensive red phosphorus has emerged as a promising anode material of potassium-ion batteries(PIBs) for its large theoretical capacities and low redox potentials in the multielectron alloying/dea...The resourceful and inexpensive red phosphorus has emerged as a promising anode material of potassium-ion batteries(PIBs) for its large theoretical capacities and low redox potentials in the multielectron alloying/dealloying reactions,yet chronically suffering from the huge volume expansion/shrinkage with a sluggish reaction kinetics and an unsatisfactory interfacial stability against volatile electrolytes.Herein,we systematically developed a series of localized high-concentration electrolytes(LHCE) through diluting high-concentration ether electrolytes with a non-solvating fluorinated ether to regulate the formation/evolution of solid electrolyte interphases(SEI) on phosphorus/carbon(P/C) anodes for PIBs.Benefitting from the improved mechanical strength and structural stability of a robust/uniform SEI thin layer derived from a composition-optimized LHCE featured with a unique solvation structure and a superior K+migration capability,the P/C anode with noticeable pseudocapacitive behaviors could achieve a large reversible capacity of 760 mA h g^(-1)at 100 mA g^(-1),a remarkable capacity retention rate of 92.6% over 200 cycles at 800 mA g^(-1),and an exceptional rate capability of 334 mA h g^(-1)at8000 mA g^(-1).Critically,a suppressed reduction of ether solvents with a preferential decomposition of potassium salts in anion-derived interfacial reactions on P/C anode for LHCE could enable a rational construction of an outer organic-rich and inner inorganic-dominant SEI thin film with remarkable mechanical strength/flexibility to buffer huge volume variations and abundant K+diffusion channels to accelerate reaction kinetics.Additionally,the highly reversible/durable full PIBs coupling P/C anodes with annealed organic cathodes further verified an excellent practical applicability of LHCE.This encouraging work on electrolytes regulating SEI formation/evolution would advance the development of P/C anodes for high-performance PIBs.展开更多
Localized high-concentration electrolytes(LHCE) have shown good compatibility with high-voltage lithium(Li)-metal batteries, but their practicality is yet to be proved in terms of cost and safety. Here we develop a hy...Localized high-concentration electrolytes(LHCE) have shown good compatibility with high-voltage lithium(Li)-metal batteries, but their practicality is yet to be proved in terms of cost and safety. Here we develop a hybrid-LHCE with favorable integrated properties by combining the merits of two representative diluents, fluorobenzene(FB) and 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether(TFE). Specifically,the extremely cheap and lightweight FB significantly reduces the cost and density of electrolyte, while the fire-retardant TFE circumvents the flammable nature of FB and thus greatly improves the safety of electrolyte. Moreover, the FB–TFE mixture enhances the thermodynamic stability of hybrid-LHCE and renders a controllable defluorination of FB, contributing to the formation of a thin and durable inorganic-rich solid electrolyte interphase(SEI) with rapid ion-transport kinetics. Benefiting from the designed hybridLHCE, a Li|NCM523 battery demonstrates excellent cycling performance(215 cycles, 91% capacity retention) under challenging conditions of thin Li-anode(30 μm) and high cathode loading(3.5 m Ah/cm^(2)).展开更多
Direct methanol fuel cells(DMFCs) have attracted extensive attention as promising next-generation energy conversion devices. However, commercialized proton exchange membranes(PEMs) hardly fulfill the demand of methano...Direct methanol fuel cells(DMFCs) have attracted extensive attention as promising next-generation energy conversion devices. However, commercialized proton exchange membranes(PEMs) hardly fulfill the demand of methanol tolerance for DMFCs employing high-concentration methanol solutions.Herein, we report a series of semi-crystalline poly(arylene ether ketone) PEMs with ultra-densely sulfonic-acid-functionalized pendants linked by flexible alkyl chains, namely, SL-SPEK-x(where x represents the molar ratio of the novel monomer containing multiple phenyl side chain to the bisfluoride monomers). The delicate structural design rendered SL-SPEK-x membranes with high crystallinity and well-defined nanoscale phase separation between hydrophilic and hydrophobic phases. The reinforcement from poly(ether ketone) crystals enabled membranes with inhibited dimensional variation and methanol penetration. Furthermore, microphase separation significantly enhanced proton conductivity. The SL-SPEK-12.5 membrane achieved the optimum trade-off between proton conductivity(0.182 S cm^(-1), 80 ℃), water swelling(13.6%, 80 ℃), and methanol permeability(1.6 × 10^(-7)cm~2 s^(-1)). The DMFC assembled by the SL-SPEK-12.5 membrane operated smoothly with a 10 M methanol solution, outputting a maximum power density of 158.3 mW cm^(-2), nearly twice that of Nafion 117(94.2 mW cm^(-2)). Overall, the novel structural optimization strategy provides the possibility of PEMs surviving in high-concentration methanol solutions, thus facilitating the miniaturization and portability of DMFC devices.展开更多
A new SOI power device with multi-region high-concentration fixed charge（MHFC） is reported. The MHFC is formed through implanting Cs or I ion into the buried oxide layer（BOX）, by which the high-concentration dynam...A new SOI power device with multi-region high-concentration fixed charge（MHFC） is reported. The MHFC is formed through implanting Cs or I ion into the buried oxide layer（BOX）, by which the high-concentration dynamic electrons and holes are induced at the top and bottom interfaces of BOX. The inversion holes can enhance the vertical electric field and raise the breakdown voltage since the drain bias is mainly generated from the BOX. A model of breakdown voltage is developed, from which the optimal spacing has also been obtained. The numerical results indicate that the breakdown voltage of device proposed is increased by 287% in comparison to that of conventional LDMOS.展开更多
The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extract...The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic oxides.This oxygen and metal extraction can be achieved using existing metallurgical techniques.Furthermore,the ample reserves of water ice on the Moon offer another means for oxygen production.This paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental conditions.It delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar regolith.The two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the Moon.Considering the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the Moon.This review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.展开更多
Binary composites(ZIF-67/rGO)were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source,2-methylimidazole as organic ligand,and reduced graphene oxide(rGO)as carbon carrier.Then...Binary composites(ZIF-67/rGO)were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source,2-methylimidazole as organic ligand,and reduced graphene oxide(rGO)as carbon carrier.Then Ru3+was introduced for ion exchange,and the porous Ru-doped Co_(3)O_(4)/rGO(Ru-Co_(3)O_(4)/rGO)composite electrocatalyst was prepared by annealing.The phase structure,morphology,and valence state of the catalyst were analyzed by X-ray powder diffraction(XRD),scanning electron microscope(SEM),transmission electron microscopy(TEM),and X-ray photoelectron spectroscopy(XPS).In 1 mol·L^(-1)KOH,the oxygen evolution reaction(OER)performance of the catalyst was measured by linear sweep voltammetry,cyclic voltammetry,and chronoamperometry.The results show that the combination of Ru doping and rGO provides a fast channel for collaborative electron transfer.At the same time,rGO as a carbon carrier can improve the electrical conductivity of Ru-Co_(3)O_(4)particles,and the uniformly dispersed nanoparticles enable the reactants to diffuse freely on the catalyst.The results showed that the electrochemical performance of Ru-Co_(3)O_(4)/rGO was much better than that of Co_(3)O_(4)/rGO,and the overpotential of Ru-Co_(3)O_(4)/rGO was 363.5 mV at the current density of 50 mA·cm^(-2).展开更多
文摘A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and Mo2S3 nanoparticles were integrated at the edges of Co3O4 nanosheets,creating a rich,heterogeneous interface that enhances the synergistic effects of each component.In an alkaline electrolyte,the synthesized CoMoNiO-S/NF-110 exhibited superior electrocatalytic performance for oxygen evolution reaction(OER),achieving current densities of 100 and 200 mA·cm^(-2) with low overpotentials of 199.4 and 224.4 mV,respectively,outperforming RuO2 and several high-performance Mo and Ni-based catalysts.This excellent performance is attributed to the rich interface formed between the components and active sites exposed by the defect structure.
文摘The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276.
基金support from the National Natural Science Foundation of China(Nos.12305373 and 52276220)the Guangzhou Basic Research Program(No.SL2024A04J00234).
文摘Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies.
基金supported by Basic Science Research Program(Priority Research Institute)through the NRF of Korea funded by the Ministry of Education(2021R1A6A1A10039823)by the Korea Basic Science Institute(National Research Facilities and Equipment Center)grant funded by the Ministry of Education(2020R1A6C101B194)。
文摘Lithium-oxygen(Li-O2)batteries are perceived as a promising breakthrough in sustainable electrochemical energy storage,utilizing ambient air as an energy source,eliminating the need for costly cathode materials,and offering the highest theoretical energy density(~3.5 k Wh kg^(-1))among discussed candidates.Contributing to the poor cycle life of currently reported Li-O_(2)cells is singlet oxygen(1O_(2))formation,inducing parasitic reactions,degrading key components,and severely deteriorating cell performance.Here,we harness the chirality-induced spin selectivity effect of chiral cobalt oxide nanosheets(Co_(3)O_(4)NSs)as cathode materials to suppress 1O_(2)in Li-O_(2)batteries for the first time.Operando photoluminescence spectroscopy reveals a 3.7-fold and 3.23-fold reduction in 1O_(2)during discharge and charge,respectively,compared to conventional carbon paperbased cells,consistent with differential electrochemical mass spectrometry results,which indicate a near-theoretical charge-to-O_(2)ratio(2.04 e-/O_(2)).Density functional theory calculations demonstrate that chirality induces a peak shift near the Fermi level,enhancing Co 3d-O 2p hybridization,stabilizing reaction intermediates,and lowering activation barriers for Li_(2)O_(2)formation and decomposition.These findings establish a new strategy for improving the stability and energy efficiency of sustainable Li-O_(2)batteries,abridging the current gap to commercialization.
基金Funded by the 111 Project(No.B17034)Open Project of Hubei Key Laboratory of Power System Design and Test for Electrical Vehicle(No.ZDSYS202212)+1 种基金Innovative Research Team Development Program of Ministry of Education of China(No.IRT_17R83)the Science and Technology Project of China Southern Power Grid Co.,Ltd.(No.GDKJXM20222546)。
文摘The development of Pt-free catalysts for the oxygen reduction reaction(ORR)is a great issue for meeting the cost challenges of proton exchange membrane fuel cells(PEMFCs)in commercial applications.In this work,a series of RuCo/C catalysts were synthesized by NaBH4 reduction method under the premise that the total metal mass percentage was 20%.X-ray diffraction(XRD)patterns and scanning electron microscopy(SEM)confirmed the formation of single-phase nanoparticles with an average size of 33 nm.Cyclic voltammograms(CV)and linear sweep voltammograms(LSV)tests indicated that RuCo(2:1)/C catalyst had the optimal ORR properties.Additionally,the RuCo(2:1)/C catalyst remarkably sustained 98.1% of its activity even after 3000 cycles,surpassing the performance of Pt/C(84.8%).Analysis of the elemental state of the catalyst surface after cycling using X-ray photoelectron spectroscopy(XPS)revealed that the Ru^(0) percentage of RuCo(2:1)/C decreased by 2.2%(from 66.3% to 64.1%),while the Pt^(0) percentage of Pt/C decreased by 7.1%(from 53.3% to 46.2%).It is suggested that the synergy between Ru and Co holds the potential to pave the way for future low-cost and highly stable ORR catalysts,offering significant promise in the context of PEMFCs.
基金financial support of the National Natural Science Foundation of China(No.52472271)the National Key Research and Development Program of China(No.2023YFE0115800)。
文摘Heteroatom-doped carbon is considered a promising alternative to commercial Pt/C as an efficient catalyst for the oxygen reduction reaction(ORR).This study presents the synthesis of iron-loaded,sulfur and nitrogen co-doped carbon(Fe/SNC)via in situ incorporation of 2-aminothiazole molecules into zeolitic imidazolate framework-8(ZIF-8)through coordination between metal ions and organic ligands.Sulfur and nitrogen doping in carbon supports effectively modulates the electronic structure of the catalyst,increases the Brunauer-Emmett-Teller surface area,and exposes more Fe-N_(x)active centers.Fe-loaded,S and N co-doped carbon with Fe/S molar ratio of 1:10(Fe/SNC-10)exhibits a half-wave potential of 0.902 V vs.RHE.After 5000 cycles of cyclic voltammetry,its half-wave potential decreases by only 20 mV vs.RHE,indicating excellent stability.Due to sulfur s lower electronegativity,the electronic structure of the Fe-N_(x)active center is modulated.Additionally,the larger atomic radius of sulfur introduces defects into the carbon support.As a result,Fe/SNC-10 demonstrates superior ORR activity and stability in alkaline solution compared with Fe-loaded N-doped carbon(Fe/NC).Furthermore,the zinc-air battery assembled with the Fe/SNC-10 catalyst shows enhanced performance relative to those assembled with Fe/NC and Pt/C catalysts.This work offers a novel design strategy for advanced energy storage and conversion applications.
基金funded by the Innovative Research Group Project of the National Natural Science Foundation of China(52121004)the Research Development Fund(No.RDF-21-02-060)by Xi’an Jiaotong-Liverpool University+1 种基金support received from the Suzhou Industrial Park High Quality Innovation Platform of Functional Molecular Materials and Devices(YZCXPT2023105)the XJTLU Advanced Materials Research Center(AMRC).
文摘Seawater zinc-air batteries are promising energy storage devices due to their high energy density and utilization of seawater electrolytes.However,their efficiency is hindered by the sluggish oxygen reduction reaction(ORR)and chlorideinduced degradation over conventional catalysts.In this study,we proposed a universal synthetic strategy to construct heteroatom axially coordinated Fe–N_(4) single-atom seawater catalyst materials(Cl–Fe–N_(4) and S–Fe–N_(4)).X-ray absorption spectroscopy confirmed their five-coordinated square pyramidal structure.Systematic evaluation of catalytic activities revealed that compared with S–Fe–N_(4),Cl–Fe–N_(4) exhibits smaller electrochemical active surface area and specific surface area,yet demonstrates higher limiting current density(5.8 mA cm^(−2)).The assembled zinc-air batteries using Cl–Fe–N_(4) showed superior power density(187.7 mW cm^(−2) at 245.1 mA cm^(−2)),indicating that Cl axial coordination more effectively enhances the intrinsic ORR activity.Moreover,Cl–Fe–N_(4) demonstrates stronger Cl−poisoning resistance in seawater environments.Chronoamperometry tests and zinc-air battery cycling performance evaluations confirmed its enhanced stability.Density functional theory calculations revealed that the introduction of heteroatoms in the axial direction regulates the electron center of Fe single atom,leading to more active reaction intermediates and increased electron density of Fe single sites,thereby enhancing the reduction in adsorbed intermediates and hence the overall ORR catalytic activity.
基金funded by the National Nature Science Foundation of China(62264006,62574102)“Thousand Talents Program”of Yunnan Province for Young Talents,Innovative Research Teams(in Science and Technology)in the University of Yunnan Province(IRTSTYN),XingDian Talent Support Program for Young Talents,and Frontier Research Team of Kunming University 2023,The Basic Research Project of Yunnan Province(Nos.202201AU070022)+2 种基金Kunming University Talent Introduction Fund(Nos.YJL20024)Yunnan Province Education Department Scientific Research Fund Project(Nos.2024Y759)Undergraduate Innovation and Entrepreneurship Training Program Project of Yunnan Provincial(202411393005)。
文摘Carbon-based air cathodes offer low cost,high electrical conductivity,and structural tunability.However,they suffer from limited catalytic activity and inefficient gas transport,and they typically rely on noble metal additives or complex multilayer configurations.To tackle these issues,this study devised a self-activated integrated carbon-based air cathode.By integrating in situ catalytic site construction with structural optimization,the strategy not only induces the formation of oxygen functional groups(─C─OH,─C═O,─COOH),hierarchical pores,and uniformly distributed active sites,but also establishes a favorable electronic and mass-transport environment.Furthermore,the roll-pressing-based integrated design streamlines electrode construction,reinforces interfacial bonding,and significantly enhances mechanical stability.Density functional theory(DFT)calculations show that oxygen functional groups initiate hydrogen bonding interaction and promote charge enrichment,which improves the activity of the cathode and facilitates intermediate adsorption/desorption in oxygen reduction and evolution reactions processes.As a result,the integrated air cathode-based rechargeable zinc-air batteries(RZABs)achieve a high specific capacity of 811 mAh g^(-1).It also performs well in quasi-solid-state RZABs and silicon-air batteries systems across a wide temperature range,demonstrating strong adaptability and application potential.This study provides a scalable and cost-effective design strategy for high-performance carbon-based air cathodes,offering new insights into advancing durable and practical metal-air energy systems.
基金supported by the Major Science and Technology Special Plan of Yunnan Province(Nos.202302AB080012 and 202402AB080004)the National Natural Science Foundation of China(No.22264025)+1 种基金the Basic Research Foundation of Yunnan Province(Nos.202401AS070033 and 202501AT070055)the Reserve talents for young and middleaged academic and technical leaders project of Yunnan Province(No.202405AC350071).
文摘Oxygen evolution reaction(OER)is a key step in hydrogen production by water electrolysis technology.How-ever,developing efficient,stable,and low-cost OER electrocatalysts is still challenging.This article presents the preparation of a series of novel copper iridium nanocatalysts with heterostructures and low iridium content for OER.The electrochemical tests revealed higher OER of Cu@Ir_(0.3) catalyst under acidic conditions with a generated current density of 10 mA/cm^(2) at only 284 mV overpotential.The corresponding OER mass activity was estimated to be 1.057 A/mgIr,a value 8.39-fold higher than that of the commercial IrO_(2).After 50 h of endurance testing,the Cu@Ir_(0.3) catalyst preserved excellent catalytic activity with a negligible rise in overpotential and maintained a good heterostructures.Cu@Ir_(0.3) The excellent OER activity can be attributed to its heterostructure,as con-firmed by density functional theory(DFT)calculations,indicating that Cu@Ir The coupling between isoquanta causes charge redistribution,optimizing the adsorption energy of unsaturated Ir sites for oxygen intermediates and reducing the energy barrier of OER free energy determining the rate step.In summary,this method provides a new approach for designing efficient,stable,and low iridium content OER catalysts.
基金supported by the National Natural Science Foundation of China(Regional Fund)(No.51868054)the Natural Science Foundation of Inner Mongolia of China(General Program)(No.2022MS05052).
文摘4-Nitrophenol(4-NP),a toxic and persistent pollutant in chemical wastewater,presents significant challenges in degradation and mineralization.Conventional ozone oxidation catalysts are hindered by low efficiency,mass transfer constraints and metal leaching,necessitating the development of stable and efficient catalysts.Herein,BCn-H/MS,the derivative of Bi(Ce)-MOF,was prepared by in situ incorporation,thermal decomposition and acid etching.The resulting materials were characterized and employed in catalytic ozonation for the reduction of 4-NP.Under the specific experimental conditions of the O_(3)+BC0.3-H/MS system,the total organic carbon(TOC)and chemical oxygen demand(COD)removal rates of 4-NP were observed to reach 94.6%and 91.8%within 30 min,respectively.These two parameters were improved by raising the initial pH,reducing the pollutant concentration and increasing the catalyst dosage.The abundant oxygen vacancies(OVs)were regarded as the pivotal catalytic site of BC0.3-H/MS,which was conducive to the adsorption of O_(3) and the acceleration of the formation of reactive oxygen species(ROS).The regular hollow square structure effectively boosted the specific surface area,increased OVs exposure and accelerated the adsorption and mass transfer process.The electron paramagnetic resonance(EPR)results demonstrated that the primary ROS engaged in the degradation reaction were⋅OH and⋅O_(2)−.BC0.3-H/MS demonstrated excellent stability and reusability in cyclic experiments.Toxicity analysis revealed that the O_(3)+BC0.3-H/MS system exhibited an effective detoxification effect.Ultimately,the primary degradation pathway of 4-NP was proposed through liquid chromatography-mass spectroscopy(LC-MS)and in-situ diffuse reflectance infrared fourier-transform spectroscopy(DRIFTS)analyses at varying reaction times.
基金supported by the National Natural Science Foundation of China (Grant Nos.12325406,92261201,12404305,and W2512072)the Shaanxi Province Natural Science Fundamental Research Project (Grant Nos.2023JC-XJ-03 and23JSQ013)the China Postdoctoral Science Foundation (Grant Nos.BX20240286 and 2024M7625)。
文摘Abiotic oxygen formation predates photosynthesis,sustaining early chemical evolution,yet its elementary mechanisms remain contested.Here,we show the production pathways for molecular oxygen from doubly ionized carbon dioxide upon electron-impact.Through fragment ions and electron coincidence momentum imaging,we unambiguously determine the ionization mechanism by measuring the projectile energy loss in association with the C^(+) +O_(2)^(+) channel.Further potential energy and trajectory calculations enable us to elucidate the dynamical details of this fragmentation process,in which a bond rearrangement pathway is found to proceed via the structural deformation to a triangular intermediate.Moreover,we demonstrate a further roaming pathway for the formation of O_(2)^(+) from CO_(2)^(+) 2,in which a frustrated C-O bond cleavage leaves the O atom without sufficient energy to escape.The O atom then wanders around varied configuration spaces of the flat potential energy regions and forms a C-O-O_(2)^(+) intermediate prior to the final products C^(+) +O_(2)^(+).Considering the large quantities of free electrons in interstellar space,the processes revealed here are expected to be significant and should be incorporated into atmospheric evolution models.
基金financially supported by National Key Research and Development Program of China(No.2019YFA0705603)National Natural Science Foundation of China(No.22078341,No.21808228 and No.21776290)+1 种基金Science Fund for Creative Research Groups of the National Natural Science Foundation of China(No.21921005)S&T Program of Hebei(No.B2020103028).
文摘The key to realize long-life high energy density lithium batteries is to exploit functional electrolytes capable of stabilizing both high voltage cathode and lithium anode.The emergence of localized high-concentration electrolytes(LHCEs)shows great promise for ameliorating the above-mentioned interfacial issues.In this work,a lithium difluoro(oxalate)borate(LiDFOB)based nonflammable dual-anion LHCE is designed and prepared.Dissolving in the mixture of trimethyl phosphate(TMP)/1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropylether(D_(2)),the continuously consumption of LiDFOB is suppressed by simply introducing lithium nitrate(LiNO_(3)).Meantime,as most of the TMP molecular are coordinated with Li^(+),the electrolyte does not show incompatibility issue between neither metal lithium nor graphite anode.Therefore,it demonstrates excellent capability in stabilizing the interface of Ni-rich cathode and regulating lithium deposition morphology.The Li||LiNi_(0.87)Co_(0.08)Mn_(0.05)O_(2)(NCM87)batteries exhibit high capacity retention of more than 90%after 200 cycles even under the high cutoff voltage of 4.5 V,1 C rate.This study offers a prospective method to develop safe electrolytes suitable for high voltage applications,thus providing higher energy densities.
基金supported by the Natural Science Foundation of Gansu Province for Youths(21JR7RA254)the Gansu Provincial Department of Education: Innovation Fund Project(2022A-029)+1 种基金the Major Special Fund of Gansu Province(21ZD4GA031)the Lanzhou University of Technology Hongliu First-class Discipline Construction Program and Gansu Province Central Government Guided Local Science and Technology Development Fund ProjectIndustrialization of Automotive Low-Temperature Lithium-ion Battery Manufacturing Technology Achievements。
文摘By optimizing electrolyte formulation to inhibit the deposition of transition metal ions(TMIs) on the surface of the graphite anode is an effective way to improve the electrochemical performance of lithium-ion batteries.At present,it is generally believed the formation of an effective interfacial film on the surface of the anode electrode is the leading factor in reducing the dissolution of TMIs and prevent TMIs from being embedded in the electrode.It ignores the influence of the solvation structures in the electrolyte system with different composition,and is not conducive to the design of the electrolyte formulation from the perspective of changing the concentration and the preferred solvent to inhibit the degradation of battery performance caused by TMIs deposition.In this work,by analyzing the special solvation structures of the high-concentra tion electrolyte,we study the main reason why high-concentration electrolyte inhibits the destructive effect of Mn(Ⅱ) on the electrochemical performance of LIBs.By combining the potentialresolved in-situ electrochemical impedance spectroscopy technology(PRIs-EIS) and density functional theory(DFT) calculation,we find that Mn(Ⅱ) mainly exists in the form of contact ions pairs(CIPs) and aggregates(AGGs) in high-concentration electrolyte.These solvation structures can reduce the destructive effect of Mn(Ⅱ) on battery performance from two aspects:on the one hand,it can rise the lowest unoccupied orbital(LUMO) value of the solvation structures of Mn(Ⅱ),thereby reducing the chance of its reduction;on the other hand,the decrease of Mn2+ions reduction can reduce the deposition of metallic manganese in the solid electrolyte interphase(SEI),thereby avoiding the continuous growth of the SEI.This study can be provided inspiration for the design of electrolytes to inhibit the destructive effect of TMls on LIBs.
基金National Natural Science Foundation of China,Grant/Award Number:22179006Natural Science Foundation of Zhejiang Province,Grant/Award Number:LQ23E020002+4 种基金National Natural Science Foundation of China,Grant/Award Numbers:52202284,52072036Cooperation between Industry and Education Project of Ministry of Education,Grant/Award Number:220601318235513WenZhou Natural Science Foundation,Grant/Award Numbers:G20220019,G20220021State Key Laboratory of Electrical Insulation and Power Equipment,Xi'an Jiaotong University,Grant/Award Number:EIPE22208Key Research and Development Program of Henan province,China,Grant/Award Number:231111242500。
文摘The commercialization of silicon-based anodes is affected by their low initial Coulombic efficiency(ICE)and capacity decay,which are attributed to the formation of an unstable solid electrolyte interface(SEI)layer.Herein,a feasible and cost-effective prelithiation method under a localized highconcentration electrolyte system(LHCE)for the silicon-silica/graphite(Si-SiO_(2)/C@G)anode is designed for stabilizing the SEI layer and enhancing the ICE.The thin SiO_(2)/C layers with-NH_(2) groups covered on nano-Si surfaces are demonstrated to be beneficial to the prelithiation process by density functional theory calculations and electrochemical performance.The SEI formed under LHCE is proven to be rich in ionic conductivity,inorganic substances,and flexible organic products.Thus,faster Li+transportation across the SEI further enhances the prelithiation effect and the rate performance of Si-SiO_(2)/C@G anodes.LHCE also leads to uniform decomposition and high stability of the SEI with abundant organic components.As a result,the prepared anode shows a high reversible specific capacity of 937.5 mAh g^(-1)after 400 cycles at a current density of 1 C.NCM 811‖Li-SSGLHCE full cell achieves a high-capacity retention of 126.15 mAh g^(-1)at 1 C over 750 cycles with 84.82%ICE,indicating the great value of this strategy for Si-based anodes in large-scale applications.
基金supported by the National Key Research and Development Program of China(2021YFB2400200)the National Natural Science Foundation of China(52104313,22172117,52072298)the Scientific Research Program of Shaanxi Provincial Education Department(21JK0808)。
文摘The resourceful and inexpensive red phosphorus has emerged as a promising anode material of potassium-ion batteries(PIBs) for its large theoretical capacities and low redox potentials in the multielectron alloying/dealloying reactions,yet chronically suffering from the huge volume expansion/shrinkage with a sluggish reaction kinetics and an unsatisfactory interfacial stability against volatile electrolytes.Herein,we systematically developed a series of localized high-concentration electrolytes(LHCE) through diluting high-concentration ether electrolytes with a non-solvating fluorinated ether to regulate the formation/evolution of solid electrolyte interphases(SEI) on phosphorus/carbon(P/C) anodes for PIBs.Benefitting from the improved mechanical strength and structural stability of a robust/uniform SEI thin layer derived from a composition-optimized LHCE featured with a unique solvation structure and a superior K+migration capability,the P/C anode with noticeable pseudocapacitive behaviors could achieve a large reversible capacity of 760 mA h g^(-1)at 100 mA g^(-1),a remarkable capacity retention rate of 92.6% over 200 cycles at 800 mA g^(-1),and an exceptional rate capability of 334 mA h g^(-1)at8000 mA g^(-1).Critically,a suppressed reduction of ether solvents with a preferential decomposition of potassium salts in anion-derived interfacial reactions on P/C anode for LHCE could enable a rational construction of an outer organic-rich and inner inorganic-dominant SEI thin film with remarkable mechanical strength/flexibility to buffer huge volume variations and abundant K+diffusion channels to accelerate reaction kinetics.Additionally,the highly reversible/durable full PIBs coupling P/C anodes with annealed organic cathodes further verified an excellent practical applicability of LHCE.This encouraging work on electrolytes regulating SEI formation/evolution would advance the development of P/C anodes for high-performance PIBs.
基金supported by the National Natural Science Foundation of China (No. 21808125)China Postdoctoral Science Foundation (No. 2020M672805)supported by Tsinghua National Laboratory for Information Science and Technology。
文摘Localized high-concentration electrolytes(LHCE) have shown good compatibility with high-voltage lithium(Li)-metal batteries, but their practicality is yet to be proved in terms of cost and safety. Here we develop a hybrid-LHCE with favorable integrated properties by combining the merits of two representative diluents, fluorobenzene(FB) and 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether(TFE). Specifically,the extremely cheap and lightweight FB significantly reduces the cost and density of electrolyte, while the fire-retardant TFE circumvents the flammable nature of FB and thus greatly improves the safety of electrolyte. Moreover, the FB–TFE mixture enhances the thermodynamic stability of hybrid-LHCE and renders a controllable defluorination of FB, contributing to the formation of a thin and durable inorganic-rich solid electrolyte interphase(SEI) with rapid ion-transport kinetics. Benefiting from the designed hybridLHCE, a Li|NCM523 battery demonstrates excellent cycling performance(215 cycles, 91% capacity retention) under challenging conditions of thin Li-anode(30 μm) and high cathode loading(3.5 m Ah/cm^(2)).
基金supported by the program of Jilin Provincial Department of Science and Technology (YDZJ202301ZYTS320)。
文摘Direct methanol fuel cells(DMFCs) have attracted extensive attention as promising next-generation energy conversion devices. However, commercialized proton exchange membranes(PEMs) hardly fulfill the demand of methanol tolerance for DMFCs employing high-concentration methanol solutions.Herein, we report a series of semi-crystalline poly(arylene ether ketone) PEMs with ultra-densely sulfonic-acid-functionalized pendants linked by flexible alkyl chains, namely, SL-SPEK-x(where x represents the molar ratio of the novel monomer containing multiple phenyl side chain to the bisfluoride monomers). The delicate structural design rendered SL-SPEK-x membranes with high crystallinity and well-defined nanoscale phase separation between hydrophilic and hydrophobic phases. The reinforcement from poly(ether ketone) crystals enabled membranes with inhibited dimensional variation and methanol penetration. Furthermore, microphase separation significantly enhanced proton conductivity. The SL-SPEK-12.5 membrane achieved the optimum trade-off between proton conductivity(0.182 S cm^(-1), 80 ℃), water swelling(13.6%, 80 ℃), and methanol permeability(1.6 × 10^(-7)cm~2 s^(-1)). The DMFC assembled by the SL-SPEK-12.5 membrane operated smoothly with a 10 M methanol solution, outputting a maximum power density of 158.3 mW cm^(-2), nearly twice that of Nafion 117(94.2 mW cm^(-2)). Overall, the novel structural optimization strategy provides the possibility of PEMs surviving in high-concentration methanol solutions, thus facilitating the miniaturization and portability of DMFC devices.
基金supported by the State Key Laboratory of Electronic Thin Films and Integrated Devices of China(Grant No.KFJJ201205)the Department of Education Project of Guangxi Province,China(Grant No.201202ZD041)+1 种基金the Postdoctoral Science Foundation Project of China(Grant Nos.2012M521127 and2013T60566)the National Natural Science Foundation of China(Grant Nos.61361011,61274077,and 61464003)
文摘A new SOI power device with multi-region high-concentration fixed charge（MHFC） is reported. The MHFC is formed through implanting Cs or I ion into the buried oxide layer（BOX）, by which the high-concentration dynamic electrons and holes are induced at the top and bottom interfaces of BOX. The inversion holes can enhance the vertical electric field and raise the breakdown voltage since the drain bias is mainly generated from the BOX. A model of breakdown voltage is developed, from which the optimal spacing has also been obtained. The numerical results indicate that the breakdown voltage of device proposed is increased by 287% in comparison to that of conventional LDMOS.
基金financially supported by the National Natural Science Foundation of China(Nos.52404328,52274412,and 52374418)the China Postdoctoral Science Foundation(No.2024M753248)。
文摘The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic oxides.This oxygen and metal extraction can be achieved using existing metallurgical techniques.Furthermore,the ample reserves of water ice on the Moon offer another means for oxygen production.This paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental conditions.It delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar regolith.The two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the Moon.Considering the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the Moon.This review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.
文摘Binary composites(ZIF-67/rGO)were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source,2-methylimidazole as organic ligand,and reduced graphene oxide(rGO)as carbon carrier.Then Ru3+was introduced for ion exchange,and the porous Ru-doped Co_(3)O_(4)/rGO(Ru-Co_(3)O_(4)/rGO)composite electrocatalyst was prepared by annealing.The phase structure,morphology,and valence state of the catalyst were analyzed by X-ray powder diffraction(XRD),scanning electron microscope(SEM),transmission electron microscopy(TEM),and X-ray photoelectron spectroscopy(XPS).In 1 mol·L^(-1)KOH,the oxygen evolution reaction(OER)performance of the catalyst was measured by linear sweep voltammetry,cyclic voltammetry,and chronoamperometry.The results show that the combination of Ru doping and rGO provides a fast channel for collaborative electron transfer.At the same time,rGO as a carbon carrier can improve the electrical conductivity of Ru-Co_(3)O_(4)particles,and the uniformly dispersed nanoparticles enable the reactants to diffuse freely on the catalyst.The results showed that the electrochemical performance of Ru-Co_(3)O_(4)/rGO was much better than that of Co_(3)O_(4)/rGO,and the overpotential of Ru-Co_(3)O_(4)/rGO was 363.5 mV at the current density of 50 mA·cm^(-2).
