查看更多>>摘要：Promoting inorganic-rich solid-electrolyte interphase(SEI)formation by constructing anion-rich solvated structures is a promising strategy for improving the long-term cycling of lithium-metal batteries.However,the increase of anions within the solvated structure inevitably reduces the coordination of Li+with the solvent,which leads to a low lithium diffusion coefficient and a decreased lithium conduc-tivity.Here,high entropy electrolyte is achieved by increasing the molecular diversity in electrolyte.Multiple anions(TFSI-,FSI-,NO3-and PF6-)presented in entropy electrolyte individually coordinate with Li+,creating a diverse and anion-rich solvation structure.The large variety of solvation structures leads to a diversified Li+diffusion barriers in the electrolyte,which results in the increase of channels available for Li+diffusion.Thus,three-dimensional diffusion with high Li+diffusion coefficient occurs in HE elec-trolytes.Furthermore,the anion-rich solvation structures promote the formation of the inorganic-rich SEI.As a result,over 2000 h of reversible Li plating/stripping with a low overpotential less than 27 mV is achieved in Li||Li cell using electrolyte modified by high-entropy strategy.Besides,the Li||LFP full cell with a negative capacity/positive capacity(N/P)ratio of 4.52 exhibits remarkably enhanced cycling sta-bility,retaining 83.6％of its initial capacity after 150 cycles.This strategy offers a novel approach for accelerating Li+transport kinetics and constructing stable SEI in lithium metal batteries.
查看更多>>摘要：Thermocatalytic CO2 hydrogenation with"green"H2 is one of the most promising carbon-negative tech-nologies,wherein oxygen vacancy engineering serves as a novel strategy to boost the catalytic perfor-mance of oxide-containing catalysts.To provide theoretical guidance and promote technical progress in this important field,the status and prospect of oxygen vacancy-boosted thermocatalytic CO2 hydro-genation have been thoroughly reviewed herein.Specifically,fundamentals including origin,construc-tion,characterization,and function of oxygen vacancies will be systematically summarized and oxygen vacancy-boosted hydrogenation reactions including methanation,reverse water-gas shift(RWGS),methanol synthesis,and other hydrogenation processes will be comprehensively introduced.In addition,challenges and opportunities from the perspective of engineering strategies,promoting effects,and medi-ating mechanisms of oxygen vacancies will be succinctly proposed.Overall,this review is expected to gain more insights into the role of oxygen vacancies and shed new light on the design of efficient oxide-containing catalysts.
查看更多>>摘要：The electrocatalytic conversion of CO2 into valuable chemical feedstocks using renewable electricity offers a compelling strategy for closing the carbon loop.While copper-based materials are effective in catalyzing CO2 to C2+products,the instability of Cu+species,which tend to reduce to Cu0 at cathodic potentials during CO2 reduction,poses a significant challenge.Here,we report the development of Sm-Cu2O and investigate the influence of f-d orbital hybridization on the CO2 reduction reaction(CO2RR).Supported by density functional theory(DFT)calculations,our experimental results demonstrate that hybridization between Sm3+4f and Cu+3d orbitals not only improves the adsorption of*CO intermediates and increases CO coverage to stabilize Cu+but also facilitates CO2 activation and lowers the energy bar-riers for C—C coupling.Notably,Sm-Cu2O achieves a Faradaic efficiency for C2H4 that is 38％higher than that of undoped Cu2O.Additionally,it sustains its catalytic activity over an extended operational period exceeding 7 h,compared to merely 2 h for the undoped sample.This research highlights the potential off-d orbital hybridization in enhancing the efficacy of copper-based catalysts for CO2RR,pointing towards a promising direction for the development of durable,high-performance electrocatalysts for sustainable chemical synthesis.
查看更多>>摘要：Metal-free carbon-based materials offer a promising alternative to Pt-based catalysts for the oxygen reduction reaction(ORR).However,challenges persist due to its sluggish kinetics and poor acid ORR performance.Here,we introduce a novel nitrogen-doped porous carbon with rich defects sites(such as pentagons,edge and vacancy defects)(PV/HPC)via a simple etching strategy.The PV/HPC demon-strates long-term stability and exceptional catalytic activity with half-wave potential of 0.9 V and average electron transfer number of 3.98 in alkaline solution while 0.78 V and 3.78 in acidic solution,indicating its efficiency and robustness as an ORR catalyst.Additionally,it achieves a higher kinetic current density of 91.9 mA cm-2 at 0.8 V,which is 1.75 times that of Pt/C(52.5 mA cm-2).Furthemore,it enables Al-air battery to attain a maximum power density of 487 mW cm-2,compared to 477 mW cm-2 for the Pt/C catalyst.Density functional theory(DFT)calculations elucidate that the introduction of multifunctional defects in nitrogen-doped porous carbon collectively reduces the reaction energy barrier of the departure of OH*and boosts the oxygen reduction reaction kinetics.This work presents a simple method to design durable and effective carbon-based ORR catalysts.
查看更多>>摘要：Rechargeable lithium batteries with high-capacity cathodes/anodes promise high energy densities for next-generation electrochemical energy storage.However,the associated limitations at various scales greatly hinder their practical applications.Functional gradient material(FGM)design endows the electrode mate-rials with property gradient,thus providing great opportunities to address the kinetics and stability obsta-cles.To date,still no review or perspective has covered recent advancements in gradient design at multiple scales for boosting lithium battery performances.To fill this void,this work provides a timely and compre-hensive overview of this exciting and sustainable research field.We begin by overviewing the fundamental features of FGM and the rationales of gradient design for improved electrochemical performance.Then,we comprehensively review FGM design for rechargeable lithium batteries at various scales,including natural or artificial solid electrolyte interphase(SEI)at the nanoscale,micrometer-scale electrode particles,and macroscale electrode films.The link between gradient structure design and improved electrochemical per-formance is particularly highlighted.The most recent research into constructing novel functional gradients,such as valence and temperature gradients,has also been explored.Finally,we discussed the current con-straints and future scope of FGM in rechargeable lithium batteries,aiming to inspire the development of novel FGM for next-generation high-performance lithium batteries.
查看更多>>摘要：Transition metals like Au,Ag,and Cu have been reported to be quite active for CO2 reduction.In this study,we use density functional theory(DFT)calculation to investigate the electronic structure and cat-alytic performance of Au,Ag,Cu and their alloys for CO2 reduction reaction(CO2RR).Theoretical calcula-tions identified the combination of Ag,Cu,and Au in a face-centered cubic(fcc)alloy as an outstanding electrocatalyst for CO2 reduction to CO,with Cu as the active site.The d-orbital projected density of state(PDOS)profile suggests that alloying alters the electronic structure of the Cu site,thereby affecting the Gibbs free energy change for the formation of*COOH intermediate(△G·COOH).To demonstrate the theo-retical prediction experimentally,we employ a top-down dealloying approach to synthesize a nano-porous structured AgCuAu alloy(NP-Ag5Cu5Au5).Electrochemical experiments validate that the ternary alloy catalyst is clearly better than unary and binary catalysts,showing a Faradaic efficiency(FE)for CO over 90％across a broad potential range of 0.6 V,with a peak of approximately 96％at-0.573 V vs.RHE.This study underscores the potential of multi-component alloys in CO2RR and establishes a theoretical basis for designing efficient catalysts for CO2 utilization.
查看更多>>摘要：Captured by the environmental and economic value,the recycling of spent lithium iron phosphate(LFP)batteries has attracted numerous attentions.However,hydrometallurgical method still suffers from com-plex process,and hydrothermal method is limited by morphology control,ascribed to the strong polarity of water.Herein,supported by ethanol as crystal surface modifier,the regular(010)orientation and short b-axis are effectively tailored for regenerated LFP.As Li-storage cathode,the capacities of as-optimized LFP could reach up to 157.07 mA h g-1 at 1 C,and the stable capacity of 150.50 mA h g-1 could be remained with retention of 93.48％after 400 cycles at 1 C.Even at 10 C,their capacity could be still kept about 119.3 mA h g-1.Assisted by the detail analysis of adsorption energy,the clear growth mechanism is proposed,the lowest adsorbing energy(-4.66 eV)of ethanol on(010)crystal plane renders the ordered growth along(010)crystal plane.Given this,the work is expected to shed light on the tailoring mecha-nism of internal plane about regenerated materials,whilst providing effective strategies for high-performance regenerated LFP.
查看更多>>摘要：Aqueous aluminum-ion batteries(AIBs)are promising candidates for large-scale energy storage due to the abundant resource reserve,high theoretical capacity,intrinsic safety,and low cost of Al.However,the development of aqueous AIBs is constrained by the inefficient Al plating,inevitable parasitic side reactions,and the collapse of the cathode materials.Herein,we propose a novel Al3+/Mn2+hybrid elec-trolyte in a water-acetonitrile co-solvent system with a regulated solvation structure to realize cathode-free AIBs.The inclusion of acetonitrile as a co-solvent plays a crucial role in reducing the desol-vation energy and suppressing side reactions.The introduction of Mn2+can enable the reversible plating/stripping of Al-Mn alloy with reduced overpotentials on the anode and deposition/stripping of AlxMnO2 on the cathodic current collector to realize cathode-free AIBs.The architected AIB delivers a high dis-charge capacity of 397.9 mAh g-1,coupled with superior rate capability and stable cycling performance.Moreover,the cathode-free AIB shows superior low-temperature performance and can operate at-20 ℃ for over 120 cycles.This work provides new ideas for developing high-performance and low-cost aqueous AIBs.
查看更多>>摘要：Electrochemical nitrate reduction(ENR)is an economical and eco-friendly method for converting indus-trial wastewater into valuable ammonia under atmospheric conditions.The main challenge lies in design-ing and developing highly durable ENR electrocatalysts.This study introduces defect-rich mesoporous CuOx nanowires electrocatalyst synthesized using a novel solution-flame(sol-flame)hybrid method to control mesoporosity and introduce surface defects,thereby enhancing the electrochemical nitrate-to-ammonia production performance.We found surface defects(oxygen vacancies and Cu+)and unique mesoporous nanowire structure composed of tightly interconnected nanoparticles.The sol-flame-synthesized CuOx nanowires(sf-CuO NWs)achieved superior ammonia yield rate(0.51 mmol h-1 cm-2),faradaic efficiency(97.3％),and selectivity(86.2％)in 1 M KOH electrolyte(2000 ppm nitrate).This performance surpasses that of non-porous and less-defective CuO NWs and is attributed to the increased surface area and rapid electron transport facilitated by the distinctive morphology and gener-ated defects.Theoretical calculation further suggests oxygen vacancies enhance NO3-adsorption on the sf-CuO NWs'surface and mitigate the competing hydrogen evolution reaction.This study outlines a strategic design and simple synthesis approach for nanowire electrocatalysts that boost the efficiency of electrochemical nitrate-to-ammonia conversion.
查看更多>>摘要：Solid-state electrolytes with high oxidation stability are crucial for achieving high power density all-solid-state lithium batteries.Halide electrolytes are promising candidates due to their outstanding com-patibility with cathode materials and high Li+conductivity.However,the electrochemical stability of chloride electrolytes is still limited,leaving them unsuitable for ultrahigh voltage operation.Besides,chemical compatibility issue between sulfide and halide electrolytes affects the electrochemical perfor-mance of all-solid-state batteries.Herein,Li-ion conductor Li3+xInCl6-xOx is designed to address these challenges.Li3.25lnCl5.75O0.25 shows a Li-ion conductivity of 0.90 mS cm-1 at room temperature,a high onset oxidation voltage of 3.84 V,fewer by-products at ultrahigh operation voltage,and good chemical compatibility with Li5.5PS4.5Cl1.5.The Li3.25InCl5.75O0.25@LiNi0.7Co0.1Mn0.2O2-Li3.25InCl5.75O0.25-VGCF/Li3.25InCl5.75O0.25/Li5.5PS4.5Cl1.5/Li-In battery delivers good electrochemical performances at high operat-ing voltage.This work provides a simple,economical,and effective strategy for designing high-voltage all-solid-state electrolytes.
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