查看更多>>摘要：Electrochemical cycling of hydrogen,carbon,and nitrogen-containing molecules is of great importance to tackling energy and environmental crises and composes a central piece of the net-zero emissions sce-nario.Obtaining an in-depth understanding of interfacial processes with molecular-level information is a cornerstone to developing more advanced electrocatalysts and electrochemical interfaces and further improving reaction efficiencies to meet industrial requirements.Among various in situ characterization techniques that can probe the interfacial processes,attenuated total reflection infrared spectroscopy(ATR-IR)has gained considerable attention most recently.A systematic review of its applications is expected to stimulate further efforts in studying the above-mentioned electrochemical reactions.Herein,we summarize the basic principles of in situ ATR-IR and its applications in understanding mech-anisms of electrochemical hydrogen,carbon,and nitrogen cycling reactions,including identification of key reaction intermediates and pathways,deciphering the impacts of interfacial environments,and revealing the structure-to-performance relationship on electrocatalysts.Outlooks on challenges and opportunities faced by ATR-IR in further studying these reactions are also provided.
查看更多>>摘要：Regulating the catalyst electronic structure is critical for improving the adsorption and catalytic conver-sion of lithium polysulfides(LiPSs)in lithium-sulfur batteries(Li-S),yet which has been overlooked in current studies.In this work,structurally defined Ag30Pd4 nanoclusters were loaded onto reduced gra-phene oxide(Ag30Pd4/rGO)as a modification material for polypropylene(PP)separators to elucidate the catalytic activity towards lithium polysulfides and the impact on the electrochemical properties to lithium sulfur batteries.This unique d-π combination promotes charge transfer,influences overall charge states,and further enhances adsorption energies in potential reaction pathways with lithium polysul-fides.Consequently,the Ag30Pd4/rGO/PP modified batteries exhibited an exceptionally low-capacity decay rate of 0.026％per cycle at 1.0C over 1000 stable cycles and 9.75 mAh cm-2 excellent performance even with lean electrolyte and high sulfur loading(9.7 mg cm-2).This study paves a path for employing ultrasmall bimetallic nanoclusters to promote the polysulfides redox kinetics hence boosting the lithium-sulfur battery performance.
Thijs van RaakHuub van den BogaardFausto GallucciSirui Li...
522-528页
查看更多>>摘要：Plasma-based NOx synthesis has been considered as a sustainable alternative to the conventional Haber-Bosch process.Despite the advancements in research achieved in recent years,limited attention has been paid to the reversible dimerization reaction of NO2 to N2O4.This reaction can significantly alter the parameters considered with the process'output,such as the concentration or volume fraction of products and the energy consumption.This work aims to investigate the significance of dimerization through the-oretical analysis and experimentation.Experiments were conducted with a 2D-gliding arc reactor to eval-uate the influence of dimerization in the case of plasma reactor operation.It was observed that the dimerization reaction reached equilibrium in microseconds,resulting in a maximum hypothetical NO2 equilibrium conversion of 48.8％.For plasma experiments,the dimerization could cause a maximum error of 14.1％in product detection,which needs to be carefully considered along with the influence of temper-ature variations on the measurement.
查看更多>>摘要：Electrocatalytic reduction of CO2 to produce high value-added products is an important way to achieve sustainable production of green energy,but it is limited by high complexity of the catalyst structure and reaction process,making the rational design of the catalyst and the targeted generation of specific products a huge challenge.Herein,based on the penta-octa-graphene(POG)with sp2 and sp3 hybrid as the prototype,we theoretically guide the design of CO2 electrocatalytic reduction(CO2RR)catalyst over pure POG and TM doping POG(TM@POG).Our mechanistic study highlights two key factors in new path-way for CH4 production and catalytic performance,i.e.,TM provides electron transfer for the key inter-mediate*CHO,promoting the activation of CO2,and the type of protonation for CO2RR is determined by the charge accumulation on the O atom of the intermediates.This reduces the complexity of the reac-tion and provides a predictive effect on the formation of intermediates.More importantly,the proper val-ues of the Gibbs free energy indicate that TM@POG is an ideal catalyst candidate,especially the Fe@POG,which is superior to Cu(211)material.On this basis,three simple descriptors(Bader charge,d-band cen-ter εd and descriptor φ)based on the inherent properties of atoms were constructed to reveal the under-lying causes of the improvement of catalytic activity.Our results provide a new understanding of the'structure-performance'relationship of carbon-based electrocatalysts,thus providing a useful strategy for the design of catalysts for CO2RR.
查看更多>>摘要：Herein,we propose a simple and rapid approach for synthesizing a CuS/Ru composite that serves as a bifunctional electrocatalyst to promote hydrogen production and concurrently convert sulfion into a value-added sulfur product.This composite comprises Ru nanoclusters supported on the CuS nanostruc-ture,achieved through simple pulsed laser irradiation in liquid approach.The optimized CuS/Ru-30 elec-trocatalyst demonstrates remarkable bifunctional electrocatalytic activity,exhibiting a negligible working potential of 0.28 V(vs.RHE)for the anodic sulfion oxidation reaction(SOR)and a minimal over-potential of 182 mV for cathodic hydrogen evolution reaction(HER)to achieve 10 mA cm-2 of current density.Moreover,the CuS/Ru-30 electrocatalyst shows exceptional selectivity for converting sulfion into valuable sulfur during anodic oxidation reactions,Remarkably,in a two-electrode electrolyzer system utilizing CuS/Ru-30 as both the anode and cathode,the SOR+HER coupled water electrolysis system demands only 0.52 V to reach 10 mA cm-2,which is considerably lesser compared to the OER+HER cou-pled water electrolysis(1.85 V).The experimental results and density function theory(DFT)calculations reveal that the strong electron interaction between CuS and Ru nanoclusters generates a built-in electric field,greatly enhancing electron transfer efficiency.This significantly boosts the HER performance and facilitates the adsorption and production of sulfur intermediates.This study presents a rapid and simple strategy for synthesizing a dual-functional catalyst suitable for low-voltage hydrogen generation while facilitating the recovery of valuable sulfur sources.
查看更多>>摘要：Manganese(Mn)-based materials are considered as one of the most promising cathodes in zinc-ion bat-teries(ZIBs)for large-scale energy storage applications because of their multivalence,cost-effectiveness,natural availability,low toxicity,satisfactory capacity,and high operating voltage.In this review,the research status and related interface engineering strategies of Mn-based oxide cathode electrode mate-rials for ZIB in recent years are summarized.Specifically,the review will focus on three types of interface engineering strategies,including interface reconstruction via cathode,interface reconstruction elec-trolyte,and protection via artificial cathode-electrolyte interphase(CEI)layer,within the context of their evolution of interface layer and corresponding electrochemical performance.A series of experimental variables,such as crystal structure,electrochemical reaction mechanism,and the necessary connection for the formation and evolution of interface layer,will be carefully analyzed by combining various advanced characterization techniques and theoretical calculations.Finally,suggestions and strategies are provided for reasonably designing the cathode-electrolyte interface to realize the excellent perfor-mance of Mn-based oxide zinc-based batteries.
查看更多>>摘要：Elevating the operating voltage is an effective approach to improve the reversible capacity of ultra-high nickel layered oxide cathode LiNixCoyMnzO2(NCM,x ≥ 0.8)and solve the"range anxiety"confusion of electric vehicles.However,the undesirable surface reconstruction induced by the high cut-off voltage has a fatal impact on the thermodynamic stability of the material,inevitably leading to fast capacity degradation.Herein,a mechanical fusion aided by alcohol is suggested to create a stable olivine structure for the single-crystal(SC)ultrahigh-nickel cathode LiNi0.92Co0.04Mn0.04O2.The addition of nanoparticles effectively bridges the void of SC-NCM,builds an ideal particle grading,and significantly raises the cost efficiency,as well as promotes the cycling stability and safety of the full cell.Remarkably,the layered/oli-vine mixture forms a perfect shield by lowering the surface area between the NCM cathode and elec-trolyte,hence mitigating side reactions and contributing to an incredibly thin and stable cathode/electrolyte interface.Furthermore,the thermodynamic stability of highly delithiated NCM is improved,as both the particle cracks and structural degradation are simultaneously postponed.Consequently,the maximum temperature of the single-crystal LiNi0.92Co0.04Mn0.04O2@LiFePO4||graphite pouch full cell is dramatically reduced from 599.4 to 351.4 ℃,and the full cell achieves 88.2％capacity retention after 800 cycles,demonstrating excellent thermal stability and cycling stability.This facile strategy provides a feasible technical reference for further exploiting the ultrahigh-capacity,high-safety,and long-life Ni-rich cathode for commercial application of lithium-ion batteries(LIBs).
查看更多>>摘要：Zn electrodes are suffering the dendrite growth owing to the enrichment of local space charge,distinct exposed face and residual stress.In this work,we investigated the crystal face properties and stress state of Zn foil through static energy calculations,dynamic crystal growth analysis and finite element simula-tion of stress states.Then thermal driven is deployed to modify the exposure face and residual stress of Zn foil,aiming for a dendrite-free electrode.The calculation of surface energies and simulation of crystal growth models for different crystal faces indicate that the(001)face can maintain stability during depo-sition.Inspired by this mechanism,the(101)exposed commercial Zn foil is modified by thermal process-ing.Firstly,the exposure level of the(001)face increases,though only the peak corresponding to the(002)crystal face is observed,due to the extinction effect of the densely packed plane(001)face.Further,the surface morphology becomes smooth and the stress is released with the progresses time.These stress relief and crystal face transition process strengthen the uniformity of ion distribution,and increase the interface stability during the crystal growth,which reduce the defect sites in the deposition.As a result,the Zn electrode exhibits tiny voltage hysteresis and outstanding cycle stability,which reveals improved electrochemical performance.Additionally,Li and Na can also be improved in exposed crystal faces and release strain energy through similar methods to enhance cycling stability.
查看更多>>摘要：Lithium-sulfur(Li-S)batteries suffer from the shuttle effect of soluble lithium polysulfides(LiPSs)and slow redox kinetics,significantly limiting their practical application.Although single-atom catalysts(SACs)offer a promising strategy to address these challenges,designing materials with optimal adsorp-tion force and high catalytic activity remains a grand challenge.Here,we present a cobalt(Co)-based SAC with unique Co-O2N2 coordination structures for Li-S batteries.Both experimental and theoretical studies demonstrate that O,N-coordinated Co single atoms anchored on a porous carbon framework(Co/NOC)effectively capture LiPSs and dramatically catalyze bidirectional polysulfide conversion.The expanded carbon layer spacing facilitates lithium ions diffusion and maximizes the exposure of active sites.As a result,Li-S batteries incorporating Co/NOC as separators exhibit outstanding rate performance(906.6 mAh g-1 at 3 C)and exceptional cycling stability,even at-10 ℃.Furthermore,with a high sulfur loading of 12.0 mg cm-2,the areal specific capacity reaches up to 12.36 mAh cm-2.This work provides some use-ful insights for the design of high-performance SACs for Li-S batteries.
查看更多>>摘要：To meet the demand for high-performance LiCoO2 batteries,it is necessary to overcome challenges such as interface degradation and rapid capacity degradation caused by changes in bulk structure,especially under deep delithiation and high temperature conditions.The ion conductive coating layer of Li3PO4 has been directly modified on the surface of LiCoO2 particles using magnetron sputtering method,signifi-cantly improving the lithium storage performance of LiCoO2@Li3PO4 composites.Compared to pure LiCoO2,the modified LiCoO2 sample exhibits obviously better cycle life and high-temperature perfor-mance.Especially,under the conditions of 2 and 1 C,the LiCoO2@Li3PO4 electrode delivers excellent cycling performance at high voltage of 4.5 V,with capacity retention rates of 89.7％and 75.7％at room temperature and high temperature of 45 ℃,being far greater than those of 12.3％and 29.1％for bare LiCoO2 electrodes.It is discovered that the Li3PO4 coating layer not only effectively enhances interface compatibility and suppresses the irreversible phase transition of LiCoO2,but also further improves the Li+transport kinetics and significantly reduces battery polarization,ultimately enabling the modified LiCoO2 electrode to exhibit excellent lithium storage performance and thermal safety characteristics under high voltage conditions.Thus,such effective modified strategy can undoubtedly provide an impor-tant academic inspiration for LiCoO2 implication.
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