Oxygen evolution and oxygen reduction are considered as essential processes in the energy conversion devices.The progress of cost-effective bifunctional catalysts has become a critical issue to be solved.Here,we repor...Oxygen evolution and oxygen reduction are considered as essential processes in the energy conversion devices.The progress of cost-effective bifunctional catalysts has become a critical issue to be solved.Here,we report that Co(OH)_(2)@N-doped carbon(NC)was facilely synthesized through the impregnation strategy of metal-organic frameworks derived carbon and cobalt ions.N-doped carbon with porous structure and cobalt hydroxide nanosheets play a synergistic effect role,representing excellent catalytic performance toward oxygen evolution and reduction reactions.The obtained Co(OH)_(2)@NC exhibits remarkable activity in terms of a lower overpotential of 330 mV@10 mA cm^(-2) for OER and a more positive half-wave potential(E_(1/2)=0.84 V)for ORR in alkaline medium,outperforming IrO_(2) and Pt/C.Due to its superior bifunctional catalytic performance,Co(OH)_(2)@NC catalyst is applied into a promising air electrode of Zn-air battery.This presented strategy of impregnation synthesis in this work provides a new design direction for practical electrochemical energy devices.展开更多
Silica nanoparticles-stabilized cobalt and nitrogen-doped carbon materials were synthesized through pyrolysis of metal-organic-framework of ZIF-67 supported by silica nanoparticles.The experimental results reveal that...Silica nanoparticles-stabilized cobalt and nitrogen-doped carbon materials were synthesized through pyrolysis of metal-organic-framework of ZIF-67 supported by silica nanoparticles.The experimental results reveal that the introduction of the silica nanoparticles can stabilize the microstructure of the derived CoN-C materials,which in turn exhibits the promising electrocatalytic activity towards both oxygen reduction and oxygen evolution reactions.The optimized sample exhibits a better oxygen reduction activity than commercial Pt/C catalyst as confirmed by the positive shift of half-wave potential by 20 mV while it has a low overpotential of 273 mV for oxygen evolution reactions with the retained performance over 80%after 25,000 s of continuous operation.It is demonstrated that the introduction of support frame might be an effective way to improve the activity and stability of metal-organic-framework derived electrocatalyst with stabilized microstructure.展开更多
The development of economical,highly efficient,and stable bifunctional electrocatalysts for both the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR)remains a critical focus in advancing rechargeab...The development of economical,highly efficient,and stable bifunctional electrocatalysts for both the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR)remains a critical focus in advancing rechargeable metal-air battery systems.Significant progress has been made in the design of high-performance bifunctional electrocatalysts,the development of novel oxygen electrode architectures,and the in-depth understanding of electrocatalytic mechanisms through combined experimental and computational studies.This work provides a comprehensive review of recent advancements in design strategies for oxygen catalysts,including homogeneous electrodes,asymmetric electrodes,and biomimetic electrodes,are thoroughly discussed and summarized.Then,the advanced catalyst modification strategies for ORR/OER are summarized,focusing on critical factors such as enhancement effect of metal/nonmental and synergistic enhancement effect in multiple catalyst.Subsequently,a representative performance evaluation is presented,based on the reported oxygen electrodes used in rechargeable metal-air battery applications.By focusing on these key areas,the review outlines the current challenges and future prospects for the development of bifunctional oxygen electrocatalysts,aiming to guide the design of high-performance bifunctional electrocatalysts and to elucidate the underlying mechanisms involved.展开更多
Development of high-efficiency bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalysts is vital for the widespread application of zinc-air batteries(ZABs).However,it still remains...Development of high-efficiency bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalysts is vital for the widespread application of zinc-air batteries(ZABs).However,it still remains a great challenge to avoid the inhomogeneous distribution and aggregation of metal single-atomic active centers in the construction of bifunctional electrocatalysts with atomically dispersed multimetallic sites because of the common calcination method.Herein,we report a novel catalyst with phthalocyanine-assembled Fe-Co-Ni single-atomic triple sites dispersed on sulfur-doped graphene using a simple ultrasonic procedure without calcination,and X-ray absorption fine structure(XAFS),aberration-corrected scanning transmission electron microscopy(AC-STEM),and other detailed characterizations are performed to demonstrate the successful synthesis.The novel catalyst shows extraordinary bifunctional ORR/OER activities with a fairly low potential difference(ΔE=0.621 V)between the OER overpotential(Ej10=315 mV at 10 m A cm^(-2))and the ORR half-wave potential(Ehalf-wave=0.924 V).Moreover,the above catalyst shows excellent ZAB performance,with an outstanding specific capacity(786 mAh g^(-1)),noteworthy maximum power density(139 mW cm^(-2)),and extraordinary rechargeability(discharged and charged at 5 mA cm^(-2) for more than 1000 h).Theoretical calculations reveal the vital importance of the preferable synergetic coupling effect between adjacent active sites in the Fe-Co-Ni trimetallic single-atomic sites during the ORR/OER processes.This study provides a new avenue for the investigation of bifunctional electrocatalysts with atomically dispersed trimetallic sites,which is intended for enhancing the ORR/OER performance in ZABs.展开更多
Hydrogen evolution reaction(HER)is unavoidable in many electrochemical synthesis systems,such as CO_(2)reduction,N2reduction,and H_(2)O_(2)synthesis.It makes those electrochemical reactions with multiple electron-prot...Hydrogen evolution reaction(HER)is unavoidable in many electrochemical synthesis systems,such as CO_(2)reduction,N2reduction,and H_(2)O_(2)synthesis.It makes those electrochemical reactions with multiple electron-proton transfers more complex when determining kinetics and mass transfer information.Understanding how HER competes with other electrochemical reduction reactions is crucial for both fundamental studies and system performance improvements.In this study,we employed the oxygen reduction reaction(ORR)as a model reaction to investigate HER competition on a polycrystalline-Au surface,using a rotating ring and disk electrode.It’s proved that water molecules serve as the proton source for ORR in alkaline,neutral,and even acidic electrolytes,and a 4-electron process can be achieved when the overpotential is sufficiently high.The competition from H⁺reduction becomes noticeable at the H⁺concentration higher than 2 mmol L^(–1)and intensi-fies as the H^(+)concentration increases.Based on the electrochemical results,we obtained an equivalent circuit diagram for the ORR system with competition from the H+reduction reaction,showing that these reactions occur in parallel and compete with each other.Electrochemical impedance spectroscopy measurements further confirm this argument.Additionally,we discover that the contribution of H+mass transfer to the total H^(+)reduction current is significant and comparable to the kinetic current.We believe this work will deepen our understanding of HER and its competition in electrochemical reduction systems.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
Inspired by hexaazanaphthalene-based conjugated copper metal-organic framework(HATNA-Cu-MOF),we designed 161 HATNA-TM-MOF-based SACs(TM@N_(x)O_(4-x)-HATNA)with varying TM or ligands creating distinct coordination envi...Inspired by hexaazanaphthalene-based conjugated copper metal-organic framework(HATNA-Cu-MOF),we designed 161 HATNA-TM-MOF-based SACs(TM@N_(x)O_(4-x)-HATNA)with varying TM or ligands creating distinct coordination environments(x=0-4)with superior thermodynamic and electrochemical stabilities.Volcano plots can be constructed using(AGOOH^(*)-ΔGO^(*))/ΔGO^(*)as descriptors for oxygen evolution/reduction reaction(OER/ORR)activity,also serving as target parameters for machine learning(ML)models to identify high-performance OER/ORR catalysts.The efficient monofunctional and bifunctional electrocatalysts were successfully predicted,where the ML prediction results well matched the DFT calculation results.We employed Shapley additive explanations(SHAP)for feature analysis and utilized sure independence screening and sparsification operator(SISSO)for generalization.ML analyses reveal that TM-based OER/ORR activities predominantly correlate with three key descriptors:metallic atomic radius,d-orbital electron population,and the heat of formation of the oxide,demonstrating the pivotal role of TM's inherent electronic configuration and physicochemical characteristics in governing electrocatalytic efficacy.The constant-potential approach emphasizes the key role of electric double-layer capacitance in adjusting the kinetic barrier,where changes in the Fermi level influence the occupation of d-orbitals.Variations in electrochemical potential significantly alter the electronic structure of representative Rh@N_(1)O_(3)-HATNA,affecting both the Fermi level and adsorption properties,with the unique 4d^(8)5s^(1)configuration leading to inverted O_(2)adsorption energies as the potential decreases.This study contributes insights into the origin of oxygen evolution-reduction activity for the HATNA-TM-MOF-based SACs and reveals the fundamentals of structure-activity relationships for future applications.展开更多
To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,w...To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,we report a hollow-structured Ni_(x)Co_(1−x)O/Ni_(3)S_(2)/Co_(9)S_(8)heterostructure synthesized via sequential template-assisted growth,thermal oxidation,and controlled sulfidation process.The abundant bimetallic heterointerfaces not only provide additional active sites but also promote electronic modulation via charge redistribution.Additionally,the porous and hollow architecture enhances active surface area and mass transfer ability,thereby increasing the number of accessible active sites for alkaline OER.As a result,the prepared electrocatalyst achieves low overpotential of 310 mV at 10 mA cm^(−2)and small Tafel slope of 55.94 mV dec^(−1),demonstrating the exceptional electrocatalytic performance for alkaline OER.When integrated as the anode in an AEMWE cell,it delivers outstanding performance with only 1.657 V at 1.0 A cm^(−2)and reaches high current density of 5.0 A cm^(−2)at 1.989 V,surpassing those of commercial RuO_(2).The cell also shows excellent long-term durability over 100 h with minimal degradation.This study highlights the strong potential of rationally engineered oxide/sulfide heterostructures for next-generation alkaline water electrolysis.展开更多
Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthes...Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthesized the electrode material Ce-NiCo-LDHs@SnO_(2)/NF through a two-step hydrothermal reaction,where Ce-doped NiCo-LDHs are grown on nickel foam modified by a SnO_(2) layer.Ce doping adjusts the internal electronic distribution of Ni Co-LDHs,while the introduction of the SnO_(2) layer enhances electron transfer capability.Together,these factors contribute to the reduction of the OER energy barrier and experimental evidence confirms that the reaction proceeds via the lattice oxygen evolution mechanism(LOM).Consequently,Ce-NiCo-LDHs@SnO_(2)/NF exhibits high level electrochemical performance in OER,requiring only 234 m V overpotential to achieve a current density of 10 m A/cm^(2),with a Tafel slope of just 27.39 m V/dec.When paired with Pt/C/NF,an external potential of only 1.54 V is needed to drive OWS to attain a current density amounting to 10 m A/cm^(2).Furthermore,the catalyst demonstrates stability for 100 h during the OWS stability test.This study underscores the feasibility of enhancing the OER performance through Ce doping and the introduction of a conductive SnO_(2) layer.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
Transition metal phosphides exhibit excellent efficiency in the oxygen evolution reaction under alkaline conditions,and they have garnered widespread recognition.Currently,most studies have focused on the evolution an...Transition metal phosphides exhibit excellent efficiency in the oxygen evolution reaction under alkaline conditions,and they have garnered widespread recognition.Currently,most studies have focused on the evolution and role of metal cations in the oxygen evolution reaction process,while attention to phosphorus elements is relatively scarce.Actually,phosphides possess unique properties that distinguish them from other metal compounds,and the role of phosphorus in them cannot be ignored.This study used nickel phosphide(Ni_(2)P)as a model catalyst to reveal the reconstruction and dynamic behavior of anions under alkaline conditions through cyclic voltammetry.The results indicate that as the cycle progresses,surface phosphides are converted into active oxyhydroxides.It is worth noting that the presence of the P element accelerates the rapid completion of the reconstruction process but also exhibits triple synergistic functions.First,the internal phosphorus nuclei of the active layer act as conductive scaffolds,effectively enhancing the efficiency of electron conduction.Second,the oxygen-containing anions formed in situ on metal hydroxides optimize the adsorption of reaction intermediates.Finally,the phosphorus atoms dissolved in the electrolyte suppress nickel loss,improve stability,and increase the electrochemical activity specific surface area,exposing more active sites.This study elucidates the oxygen evolution reaction mechanism of phosphides from a novel perspective,enhancing comprehension of surface reconstruction phenomena and the characteristics of active sites,guiding the rational design of phosphide pre-catalysts.展开更多
The development of atomically dispersed multi-metallic catalysts is imperative for tailoring catalytic performance and elucidating structure-activity relationships.However,synthesizing such precisely engineered archit...The development of atomically dispersed multi-metallic catalysts is imperative for tailoring catalytic performance and elucidating structure-activity relationships.However,synthesizing such precisely engineered architectures while maintaining atomic dispersion of distinct metal centers remains a formidable challenge due to thermodynamic instability and synthetic complexity.We herein propose a topological confinement pre-anchoring strategy via pre-anchoring spatially resolved Zn/Fe dual-metal sources in a structurally engineered metal-organic framework precursor to synthesize atomically dispersed ZnFe bimetallic single-atom catalysts.Extended X-ray absorption fine structure measurements and X-ray absorption near-edge structure reveal that the atomically dispersed Zn/Fe metal sites and electronic redistribution in ZnFe bimetallic single-atom catalysts.The ultrahigh surface area,hierarchical pore,and synergistic effect between Zn/Fe can greatly favor the exposure of the active site,mass transport,and improvement of intrinsic activity.Consequently,the ZnFe bimetallic single-atom catalyst demonstrates superior oxygen reduction reaction performance,achieving a half-wave potential of 0.86 V and delivering a kinetic current density of 10.1 mA cm^(-2)at 0.85 V versus RHE in 0.1 m KOH electrolyte.These metrics not only surpass those of commercial Pt/C,but also rival the highest-performing catalysts reported to date.The Zn-air battery built with ZnFe bimetallic single-atom catalyst exhibits high power density(278.5 mW cm^(-2))and specific discharging capacities(657 mAh g^(-1)).This work provides a new design pathway for constructing atomically dispersed multi-metal electrocatalysts for high-performance energy-related applications.展开更多
The oxygen evolution reaction(OER)suffers from sluggish kinetics,necessitating efficient electrocatalysts to reduce overpotentials in water splitting.Currently recognized OER mechanisms primarily include the adsorbate...The oxygen evolution reaction(OER)suffers from sluggish kinetics,necessitating efficient electrocatalysts to reduce overpotentials in water splitting.Currently recognized OER mechanisms primarily include the adsorbate evolution mechanism(AEM),lattice oxygen mechanism(LOM),and oxide path mechanism(OPM).Compared to AEM,limited by scaling relationships,and LOM,constrained by stability issues,the OPM offers a promising alternative by enabling direct O-O bond formation via dual active sites,thus bypassing^(*)OOH intermediates and lattice O involvement and achieving a balance between activity and durability.However,activating the OPM process requires precise control over the spatial and electronic structure of active sites,making the design of OPM-based catalysts challenging.While previous reviews have focused on homo/heteronuclear diatomic perspectives of OPM-based catalysts,it is urgent to systematically summarize design strategies to provide a rational reference for their development.Herein,a review of design strategies for OPM-based OER catalysts across three scales is comprehensively presented,including in-situ engineering,doping-enabled sites reconstruction,and introducing new sites for nanoparticles,direct synthesis or post-treatments for molecular catalysts,and doping or template strategies for atom pairs or arrays.The unique advantage of atom arrays is also highlighted,and their future research directions and possible strategies are discussed.This review provides a systematic summary and forward-looking perspectives for rationally designing high-performance OPM-based OER catalysts.展开更多
During the oxygen evolution reaction(OER),reconstruction of transition metal sulfides(TMSs)is inevitable.However,the lack of a clear theoretical understanding of this process has impeded the development of effective r...During the oxygen evolution reaction(OER),reconstruction of transition metal sulfides(TMSs)is inevitable.However,the lack of a clear theoretical understanding of this process has impeded the development of effective reconstruction regulation strategies.In this study,we first explored the reconstruction mechanism of CoS_(2)during OER from the perspective of electronic structure and identified two possible pathways:the OH-assisted mechanism and the O-assisted mechanism.Further verification showed that these mechanisms are universally applicable to other TMSs(e.g.,FeS_(2)).Based on the reconstruction mechanism,we investigated the basic reasons for the influence of various regulation strategies,such as vacancy modification and facet engineering,on the reconstruction ability.This verified that the method of analyzing the change in the reconstruction ability of catalysts based on the reconstruction mechanism has a high degree of applicability.Importantly,we proposed a core regulation strategy:the coordination symmetry regulation strategy.Specifically,by breaking the symmetry of the surface coordination environment of TMSs(such as introducing heteroatom doping or strain),the reconstruction process will be facilitated.Our findings provide a comprehensive mechanistic explanation for the reconstruction of TMS catalysts and offer a new idea for the rational design of OER catalysts with controllable reconstruction capacity.展开更多
Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxyge...Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxygen evolution reaction(OER)remains a significant challenge,particularly at the industrial scale.This report explores a newly discovered pathway,the oxide path mechanism(OPM) for OER-mechanism involving the oxide formation and evolution during the reaction,emphasizing its potential to overcome existing limitations.OPM enables direct O-O coupling without oxygen vacancies,offering superior stability.We detail both classical and innovative in-situ characterization techniques that are central to unraveling the OER mechanism.The advanced in-situ electrochemical techniques,such as inductively coupled plasma mass spectroscopy,X-ray photoelectron spectroscopy,and Mössbauer spectroscopy,coupled with in-situ structural analyses,provide crucial insights into the catalyst surface,the electrode-electrolyte interface and the kinetics of OER.This review provides a systematic analysis integrating classical electrochemical methods with advanced in-situ/operando techniques,specifically focusing on understanding OPM.While numerous studies have examined individual characterization methods,this study systematically integrates traditional electrochemical approaches with in-situ and operando techniques,offering critical insights into their complementary roles in elucidating reaction pathways.The integration of these methodologies provides unprecedented understanding of catalyst behavior under operational conditions,guiding the rational design of next-generation OER catalysts.Furthermore,we discuss essential standardized test toolkits and protocols,such as those for rotating disk electrode and membrane electrode assembly,which are vital for ensuring reproducibility and scalability in OER catalyst research.展开更多
The development of single atom catalysts(SACs)with asymmetric active sites by defect regulation provides an encourage potential for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER),but highly challen...The development of single atom catalysts(SACs)with asymmetric active sites by defect regulation provides an encourage potential for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER),but highly challenging.Herein,N-doped carbon(N-C)anchored atomically dispersed Ni-N_(3)site with proximity defects(Ni-N_(3)D)induced by Te atoms doping is reported.Benefitting from the inductive effect of proximity defect,the Ni-N_(3)D/Te-N-C catalyst performs excellent ORR and HER performance in alkaline and acid condition.Both in situ characterization and theoretical calculation reveal that the existence of proximity defect effect is conducive to lower rate-determining-step energy barrier of ORR and HER,thus accelerating the multielectron reaction kinetics.This work paves a novel strategy for constructing highactivity bifunctional SACs by defect engineering for development of sustainable energy.展开更多
The rational design of Ni-based catalysts is essential due to their abundance and low cost for advancing sustainable energy technologies,particularly for water splitting and fuel cells.This study employs spinpolarized...The rational design of Ni-based catalysts is essential due to their abundance and low cost for advancing sustainable energy technologies,particularly for water splitting and fuel cells.This study employs spinpolarized density functional theory(DFT)to examine the influence of anchoring rare-earth elements on the γ-NiOOH lattice surface,aiming to identify the optimal catalytic site for the oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Following the identification of an appropriate active site through Ni vacancy,a rare earth element(REE_(1))is introduced as a dopant for single-atom catalysis(SACs).The structural,thermodynamic,and catalytic characteristics of all newly designed REE_(1)/γ-NiOOH catalysts have been extensively studied.Among the newly developed catalysts,Tb_(1)/γ-NiOOH exhibits the lowest OER overpotential of(0.36 V),while Ce_(1)/γ-NiOOH and Pr_(1)/γ-NiOOH also demonstrate excellent OER performance(0.51 and 0.41 V),respectively.Notably,Nd_(1)/γ-NiOOH and Pm_(1)/γ-NiOOH exhibit efficient ORR activity,with low overpotentials of(0.63 and 0.61 V)due to their balanced adsorption and desorption energies of intermediates.Bader charge analysis reveals strong electron donation from doped REE1to the surface.This study identified Ce_(1),Pr_(1),Nd_(1),and Tb_(1) anchoring catalysts as highly promising for water-splitting applications.Moreover,Nd_(1) and Pm_(1) doping markedly improve ORR performance,underscoring their promise for enhanced electrochemical applications in metal-air batteries.The catalytic performance of all newly developed catalysts was further evaluated using electronic descriptors.The catalytic performance was further assessed using the volcano curve and scaling relationships for the adsorbed intermediates.This study offers an extensive theoretical foundation for designing cost-effective and high-performance REE_(1)/γ-NiOOH electrocatalysts.展开更多
Optimizing active sites and enhancing mass transfer capability are of paramount importance for the improvement of electrocatalyst activity.On this basis,CoFe_(2)O_(4)/CoFe nanoparticles(NPs)loaded N-doped carbon(NC)th...Optimizing active sites and enhancing mass transfer capability are of paramount importance for the improvement of electrocatalyst activity.On this basis,CoFe_(2)O_(4)/CoFe nanoparticles(NPs)loaded N-doped carbon(NC)that featured with interconnected three-dimensional(3D)ordered porous hierarchies(3DOM FeCo/NC)are prepared,and its electrocatalytic activity is studied.Due to the open structure of 3D ordered macro-pores that greatly improves the mass transfer capacity of the catalytic process and enhances the utilization of active sites inside the catalyst,as well as the uniform distribution of Fe and Co bimetallic sites on the porous skeleton,3DOM FeCo/NC exhibits superior bi-functional catalytic activities for both hydrogen evolution reaction(HER)and oxygen reduction reaction(ORR).The overpotential of HER is lower than that of commercial Pt/C when performed at high current density(>235 mA cm^(-2))in1.0 M KOH,and the half-wave potential(0.896 V)of ORR in 0.1 M KOH is also superior to that of 20% commercial Pt/C and most other similar catalysts.The effective utilization and synergistic effect of CoFe_(2)O_(4)and CoFe hetero-metallic sites remarkably enhance the electrocatalytic activity.Furthermore,3DOM FeCo/NC is assembled as an air electrode in Zn-air battery,and exhibits satisfactory maximum power density,open-circuit voltage,and charge/discharge stability over benchmark Pt/C+IrO_(2).This work contributes new insights into the design of transition-metal-based multifunctional catalysts,and has great potential for energy conversion and storage.展开更多
Solar-induced water oxidation reaction(WOR)for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages.WOR is also associate...Solar-induced water oxidation reaction(WOR)for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages.WOR is also associated with important reduction reactions,such as oxygen reduction reaction(ORR),which leads to the production of hydrogen peroxide(H_(2)O_(2)).These transitions are instrumental in the emergence and evolution of life.In this study,transition metals were loaded onto nitrogen-doped carbon(NDC)prepared under the primitive Earth's atmospheric conditions.These metal-loaded NDC samples were found to catalyze both WOR and ORR under light illumination.The chemical pathways initiated by the pristine and metal-loaded NDC were investigated.This study provides valuable insights into potential mechanisms relevant to the early evolution of our planet.展开更多
基金This work was supported by the National Natural Science Foundation of China(Nos.91963113,51701139,and U1601216)。
文摘Oxygen evolution and oxygen reduction are considered as essential processes in the energy conversion devices.The progress of cost-effective bifunctional catalysts has become a critical issue to be solved.Here,we report that Co(OH)_(2)@N-doped carbon(NC)was facilely synthesized through the impregnation strategy of metal-organic frameworks derived carbon and cobalt ions.N-doped carbon with porous structure and cobalt hydroxide nanosheets play a synergistic effect role,representing excellent catalytic performance toward oxygen evolution and reduction reactions.The obtained Co(OH)_(2)@NC exhibits remarkable activity in terms of a lower overpotential of 330 mV@10 mA cm^(-2) for OER and a more positive half-wave potential(E_(1/2)=0.84 V)for ORR in alkaline medium,outperforming IrO_(2) and Pt/C.Due to its superior bifunctional catalytic performance,Co(OH)_(2)@NC catalyst is applied into a promising air electrode of Zn-air battery.This presented strategy of impregnation synthesis in this work provides a new design direction for practical electrochemical energy devices.
基金Funded by the National Natural Science Foundation of China Guangdong(No.22279096)。
文摘Silica nanoparticles-stabilized cobalt and nitrogen-doped carbon materials were synthesized through pyrolysis of metal-organic-framework of ZIF-67 supported by silica nanoparticles.The experimental results reveal that the introduction of the silica nanoparticles can stabilize the microstructure of the derived CoN-C materials,which in turn exhibits the promising electrocatalytic activity towards both oxygen reduction and oxygen evolution reactions.The optimized sample exhibits a better oxygen reduction activity than commercial Pt/C catalyst as confirmed by the positive shift of half-wave potential by 20 mV while it has a low overpotential of 273 mV for oxygen evolution reactions with the retained performance over 80%after 25,000 s of continuous operation.It is demonstrated that the introduction of support frame might be an effective way to improve the activity and stability of metal-organic-framework derived electrocatalyst with stabilized microstructure.
基金financially supported by the National Natural Science Foundation of China(52302084)the National Key Research and Development Program of China(2022YFE0138900)+1 种基金Fundamental Research Funds for the Central Universities(2232025D-24)the Qin Shen Scholar Program of Jiaxing University。
文摘The development of economical,highly efficient,and stable bifunctional electrocatalysts for both the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR)remains a critical focus in advancing rechargeable metal-air battery systems.Significant progress has been made in the design of high-performance bifunctional electrocatalysts,the development of novel oxygen electrode architectures,and the in-depth understanding of electrocatalytic mechanisms through combined experimental and computational studies.This work provides a comprehensive review of recent advancements in design strategies for oxygen catalysts,including homogeneous electrodes,asymmetric electrodes,and biomimetic electrodes,are thoroughly discussed and summarized.Then,the advanced catalyst modification strategies for ORR/OER are summarized,focusing on critical factors such as enhancement effect of metal/nonmental and synergistic enhancement effect in multiple catalyst.Subsequently,a representative performance evaluation is presented,based on the reported oxygen electrodes used in rechargeable metal-air battery applications.By focusing on these key areas,the review outlines the current challenges and future prospects for the development of bifunctional oxygen electrocatalysts,aiming to guide the design of high-performance bifunctional electrocatalysts and to elucidate the underlying mechanisms involved.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.22305071,52472200,52271176,and52072114)the 111 Project(Grant No.D17007)+3 种基金Henan Center for Outstanding Overseas Scientists(Grant No.GZS2022017)the China Postdoctoral Science Foundation(Grant No.2022M721049)the Henan Province Key Research and Development Project(Grant No.231111520500)the Natural Science Foundation of Henan Province(Grant No.252300421556)。
文摘Development of high-efficiency bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalysts is vital for the widespread application of zinc-air batteries(ZABs).However,it still remains a great challenge to avoid the inhomogeneous distribution and aggregation of metal single-atomic active centers in the construction of bifunctional electrocatalysts with atomically dispersed multimetallic sites because of the common calcination method.Herein,we report a novel catalyst with phthalocyanine-assembled Fe-Co-Ni single-atomic triple sites dispersed on sulfur-doped graphene using a simple ultrasonic procedure without calcination,and X-ray absorption fine structure(XAFS),aberration-corrected scanning transmission electron microscopy(AC-STEM),and other detailed characterizations are performed to demonstrate the successful synthesis.The novel catalyst shows extraordinary bifunctional ORR/OER activities with a fairly low potential difference(ΔE=0.621 V)between the OER overpotential(Ej10=315 mV at 10 m A cm^(-2))and the ORR half-wave potential(Ehalf-wave=0.924 V).Moreover,the above catalyst shows excellent ZAB performance,with an outstanding specific capacity(786 mAh g^(-1)),noteworthy maximum power density(139 mW cm^(-2)),and extraordinary rechargeability(discharged and charged at 5 mA cm^(-2) for more than 1000 h).Theoretical calculations reveal the vital importance of the preferable synergetic coupling effect between adjacent active sites in the Fe-Co-Ni trimetallic single-atomic sites during the ORR/OER processes.This study provides a new avenue for the investigation of bifunctional electrocatalysts with atomically dispersed trimetallic sites,which is intended for enhancing the ORR/OER performance in ZABs.
文摘Hydrogen evolution reaction(HER)is unavoidable in many electrochemical synthesis systems,such as CO_(2)reduction,N2reduction,and H_(2)O_(2)synthesis.It makes those electrochemical reactions with multiple electron-proton transfers more complex when determining kinetics and mass transfer information.Understanding how HER competes with other electrochemical reduction reactions is crucial for both fundamental studies and system performance improvements.In this study,we employed the oxygen reduction reaction(ORR)as a model reaction to investigate HER competition on a polycrystalline-Au surface,using a rotating ring and disk electrode.It’s proved that water molecules serve as the proton source for ORR in alkaline,neutral,and even acidic electrolytes,and a 4-electron process can be achieved when the overpotential is sufficiently high.The competition from H⁺reduction becomes noticeable at the H⁺concentration higher than 2 mmol L^(–1)and intensi-fies as the H^(+)concentration increases.Based on the electrochemical results,we obtained an equivalent circuit diagram for the ORR system with competition from the H+reduction reaction,showing that these reactions occur in parallel and compete with each other.Electrochemical impedance spectroscopy measurements further confirm this argument.Additionally,we discover that the contribution of H+mass transfer to the total H^(+)reduction current is significant and comparable to the kinetic current.We believe this work will deepen our understanding of HER and its competition in electrochemical reduction systems.
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financially supported by the National Natural Science Foundation of China(Nos.62264015 and U2233206)the Civil Aviation Administration of China(No.U1933109)Hubei Province Technology Innovation Program Project(No.2024BCB073)
文摘Inspired by hexaazanaphthalene-based conjugated copper metal-organic framework(HATNA-Cu-MOF),we designed 161 HATNA-TM-MOF-based SACs(TM@N_(x)O_(4-x)-HATNA)with varying TM or ligands creating distinct coordination environments(x=0-4)with superior thermodynamic and electrochemical stabilities.Volcano plots can be constructed using(AGOOH^(*)-ΔGO^(*))/ΔGO^(*)as descriptors for oxygen evolution/reduction reaction(OER/ORR)activity,also serving as target parameters for machine learning(ML)models to identify high-performance OER/ORR catalysts.The efficient monofunctional and bifunctional electrocatalysts were successfully predicted,where the ML prediction results well matched the DFT calculation results.We employed Shapley additive explanations(SHAP)for feature analysis and utilized sure independence screening and sparsification operator(SISSO)for generalization.ML analyses reveal that TM-based OER/ORR activities predominantly correlate with three key descriptors:metallic atomic radius,d-orbital electron population,and the heat of formation of the oxide,demonstrating the pivotal role of TM's inherent electronic configuration and physicochemical characteristics in governing electrocatalytic efficacy.The constant-potential approach emphasizes the key role of electric double-layer capacitance in adjusting the kinetic barrier,where changes in the Fermi level influence the occupation of d-orbitals.Variations in electrochemical potential significantly alter the electronic structure of representative Rh@N_(1)O_(3)-HATNA,affecting both the Fermi level and adsorption properties,with the unique 4d^(8)5s^(1)configuration leading to inverted O_(2)adsorption energies as the potential decreases.This study contributes insights into the origin of oxygen evolution-reduction activity for the HATNA-TM-MOF-based SACs and reveals the fundamentals of structure-activity relationships for future applications.
基金supported by the Korea Institute for Advancement of Technology (KIAT)the Ministry of Trade,Industry&Energy (MOTIE) of the Republic of Korea (No. P0022130)by the Institute of Information&Communications Technology Planning&Evaluation(IITP)-Innovative Human Resource Development for Local Intellectualization program grant funded by the Korea government (MSIT)(IITP-2025-RS-2023-00259678)
文摘To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,we report a hollow-structured Ni_(x)Co_(1−x)O/Ni_(3)S_(2)/Co_(9)S_(8)heterostructure synthesized via sequential template-assisted growth,thermal oxidation,and controlled sulfidation process.The abundant bimetallic heterointerfaces not only provide additional active sites but also promote electronic modulation via charge redistribution.Additionally,the porous and hollow architecture enhances active surface area and mass transfer ability,thereby increasing the number of accessible active sites for alkaline OER.As a result,the prepared electrocatalyst achieves low overpotential of 310 mV at 10 mA cm^(−2)and small Tafel slope of 55.94 mV dec^(−1),demonstrating the exceptional electrocatalytic performance for alkaline OER.When integrated as the anode in an AEMWE cell,it delivers outstanding performance with only 1.657 V at 1.0 A cm^(−2)and reaches high current density of 5.0 A cm^(−2)at 1.989 V,surpassing those of commercial RuO_(2).The cell also shows excellent long-term durability over 100 h with minimal degradation.This study highlights the strong potential of rationally engineered oxide/sulfide heterostructures for next-generation alkaline water electrolysis.
基金supported by the National Natural Science Foundation of China (No.52274304)。
文摘Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthesized the electrode material Ce-NiCo-LDHs@SnO_(2)/NF through a two-step hydrothermal reaction,where Ce-doped NiCo-LDHs are grown on nickel foam modified by a SnO_(2) layer.Ce doping adjusts the internal electronic distribution of Ni Co-LDHs,while the introduction of the SnO_(2) layer enhances electron transfer capability.Together,these factors contribute to the reduction of the OER energy barrier and experimental evidence confirms that the reaction proceeds via the lattice oxygen evolution mechanism(LOM).Consequently,Ce-NiCo-LDHs@SnO_(2)/NF exhibits high level electrochemical performance in OER,requiring only 234 m V overpotential to achieve a current density of 10 m A/cm^(2),with a Tafel slope of just 27.39 m V/dec.When paired with Pt/C/NF,an external potential of only 1.54 V is needed to drive OWS to attain a current density amounting to 10 m A/cm^(2).Furthermore,the catalyst demonstrates stability for 100 h during the OWS stability test.This study underscores the feasibility of enhancing the OER performance through Ce doping and the introduction of a conductive SnO_(2) layer.
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support of the National Natural Science Foundation of China(22275035).
文摘Transition metal phosphides exhibit excellent efficiency in the oxygen evolution reaction under alkaline conditions,and they have garnered widespread recognition.Currently,most studies have focused on the evolution and role of metal cations in the oxygen evolution reaction process,while attention to phosphorus elements is relatively scarce.Actually,phosphides possess unique properties that distinguish them from other metal compounds,and the role of phosphorus in them cannot be ignored.This study used nickel phosphide(Ni_(2)P)as a model catalyst to reveal the reconstruction and dynamic behavior of anions under alkaline conditions through cyclic voltammetry.The results indicate that as the cycle progresses,surface phosphides are converted into active oxyhydroxides.It is worth noting that the presence of the P element accelerates the rapid completion of the reconstruction process but also exhibits triple synergistic functions.First,the internal phosphorus nuclei of the active layer act as conductive scaffolds,effectively enhancing the efficiency of electron conduction.Second,the oxygen-containing anions formed in situ on metal hydroxides optimize the adsorption of reaction intermediates.Finally,the phosphorus atoms dissolved in the electrolyte suppress nickel loss,improve stability,and increase the electrochemical activity specific surface area,exposing more active sites.This study elucidates the oxygen evolution reaction mechanism of phosphides from a novel perspective,enhancing comprehension of surface reconstruction phenomena and the characteristics of active sites,guiding the rational design of phosphide pre-catalysts.
基金supported by the Program for Guangdong Province Introduced Innovative and Entrepreneurial Team Program(2023ZT10L061)the NSFC Projects(Grant No.22402232)the Project supported by the Natural Science Foundation of Guangdong Province,China(Grant No.2025A1515011742).
文摘The development of atomically dispersed multi-metallic catalysts is imperative for tailoring catalytic performance and elucidating structure-activity relationships.However,synthesizing such precisely engineered architectures while maintaining atomic dispersion of distinct metal centers remains a formidable challenge due to thermodynamic instability and synthetic complexity.We herein propose a topological confinement pre-anchoring strategy via pre-anchoring spatially resolved Zn/Fe dual-metal sources in a structurally engineered metal-organic framework precursor to synthesize atomically dispersed ZnFe bimetallic single-atom catalysts.Extended X-ray absorption fine structure measurements and X-ray absorption near-edge structure reveal that the atomically dispersed Zn/Fe metal sites and electronic redistribution in ZnFe bimetallic single-atom catalysts.The ultrahigh surface area,hierarchical pore,and synergistic effect between Zn/Fe can greatly favor the exposure of the active site,mass transport,and improvement of intrinsic activity.Consequently,the ZnFe bimetallic single-atom catalyst demonstrates superior oxygen reduction reaction performance,achieving a half-wave potential of 0.86 V and delivering a kinetic current density of 10.1 mA cm^(-2)at 0.85 V versus RHE in 0.1 m KOH electrolyte.These metrics not only surpass those of commercial Pt/C,but also rival the highest-performing catalysts reported to date.The Zn-air battery built with ZnFe bimetallic single-atom catalyst exhibits high power density(278.5 mW cm^(-2))and specific discharging capacities(657 mAh g^(-1)).This work provides a new design pathway for constructing atomically dispersed multi-metal electrocatalysts for high-performance energy-related applications.
基金funding from the National Natural Science Foundation of China(22378289)the Key Central Government Guides Local Funds for Science and Technology Development(YDZJSX2022A021)the special fund for Science and Technology Innovation Teams of Shanxi Province(202304051001026)。
文摘The oxygen evolution reaction(OER)suffers from sluggish kinetics,necessitating efficient electrocatalysts to reduce overpotentials in water splitting.Currently recognized OER mechanisms primarily include the adsorbate evolution mechanism(AEM),lattice oxygen mechanism(LOM),and oxide path mechanism(OPM).Compared to AEM,limited by scaling relationships,and LOM,constrained by stability issues,the OPM offers a promising alternative by enabling direct O-O bond formation via dual active sites,thus bypassing^(*)OOH intermediates and lattice O involvement and achieving a balance between activity and durability.However,activating the OPM process requires precise control over the spatial and electronic structure of active sites,making the design of OPM-based catalysts challenging.While previous reviews have focused on homo/heteronuclear diatomic perspectives of OPM-based catalysts,it is urgent to systematically summarize design strategies to provide a rational reference for their development.Herein,a review of design strategies for OPM-based OER catalysts across three scales is comprehensively presented,including in-situ engineering,doping-enabled sites reconstruction,and introducing new sites for nanoparticles,direct synthesis or post-treatments for molecular catalysts,and doping or template strategies for atom pairs or arrays.The unique advantage of atom arrays is also highlighted,and their future research directions and possible strategies are discussed.This review provides a systematic summary and forward-looking perspectives for rationally designing high-performance OPM-based OER catalysts.
基金supported by the National Key Research and Development program(2022YFA1504000)the National Natural Science Foundation of China(22302101)+4 种基金the Fundamental Research Funds for the Central Universities(63185015)the Shenzhen Science and Technology Program(JCYJ20210324121002007,JCYJ20230807151503007)the Yunnan Provincial Science and Technology Project at Southwest United Graduate School(202402AO370001)the China Postdoctoral Science Foundation(2022M721699)the Guangdong Basic and Applied Basic Research Foundation(2024A1515010347).
文摘During the oxygen evolution reaction(OER),reconstruction of transition metal sulfides(TMSs)is inevitable.However,the lack of a clear theoretical understanding of this process has impeded the development of effective reconstruction regulation strategies.In this study,we first explored the reconstruction mechanism of CoS_(2)during OER from the perspective of electronic structure and identified two possible pathways:the OH-assisted mechanism and the O-assisted mechanism.Further verification showed that these mechanisms are universally applicable to other TMSs(e.g.,FeS_(2)).Based on the reconstruction mechanism,we investigated the basic reasons for the influence of various regulation strategies,such as vacancy modification and facet engineering,on the reconstruction ability.This verified that the method of analyzing the change in the reconstruction ability of catalysts based on the reconstruction mechanism has a high degree of applicability.Importantly,we proposed a core regulation strategy:the coordination symmetry regulation strategy.Specifically,by breaking the symmetry of the surface coordination environment of TMSs(such as introducing heteroatom doping or strain),the reconstruction process will be facilitated.Our findings provide a comprehensive mechanistic explanation for the reconstruction of TMS catalysts and offer a new idea for the rational design of OER catalysts with controllable reconstruction capacity.
基金funded by the EU H2020 Marie Skłodowska-Curie Fellowship (1439425)the National Natural Science Foundation of China (No. 52171199 and 22479011)
文摘Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxygen evolution reaction(OER)remains a significant challenge,particularly at the industrial scale.This report explores a newly discovered pathway,the oxide path mechanism(OPM) for OER-mechanism involving the oxide formation and evolution during the reaction,emphasizing its potential to overcome existing limitations.OPM enables direct O-O coupling without oxygen vacancies,offering superior stability.We detail both classical and innovative in-situ characterization techniques that are central to unraveling the OER mechanism.The advanced in-situ electrochemical techniques,such as inductively coupled plasma mass spectroscopy,X-ray photoelectron spectroscopy,and Mössbauer spectroscopy,coupled with in-situ structural analyses,provide crucial insights into the catalyst surface,the electrode-electrolyte interface and the kinetics of OER.This review provides a systematic analysis integrating classical electrochemical methods with advanced in-situ/operando techniques,specifically focusing on understanding OPM.While numerous studies have examined individual characterization methods,this study systematically integrates traditional electrochemical approaches with in-situ and operando techniques,offering critical insights into their complementary roles in elucidating reaction pathways.The integration of these methodologies provides unprecedented understanding of catalyst behavior under operational conditions,guiding the rational design of next-generation OER catalysts.Furthermore,we discuss essential standardized test toolkits and protocols,such as those for rotating disk electrode and membrane electrode assembly,which are vital for ensuring reproducibility and scalability in OER catalyst research.
基金financially supported by the National Natural Science Foundation of China(22478432,22108306,22178388)Taishan Scholars Program of Shandong Province(tsqn201909065)+2 种基金Shandong Provincial Natural Science Foundation(ZR2024JQ004)Innovation Fund Project for Graduate Student of China University of Petroleum(East China)the Fundamental Research Funds for the Central Universities(No.25CX04020A)。
文摘The development of single atom catalysts(SACs)with asymmetric active sites by defect regulation provides an encourage potential for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER),but highly challenging.Herein,N-doped carbon(N-C)anchored atomically dispersed Ni-N_(3)site with proximity defects(Ni-N_(3)D)induced by Te atoms doping is reported.Benefitting from the inductive effect of proximity defect,the Ni-N_(3)D/Te-N-C catalyst performs excellent ORR and HER performance in alkaline and acid condition.Both in situ characterization and theoretical calculation reveal that the existence of proximity defect effect is conducive to lower rate-determining-step energy barrier of ORR and HER,thus accelerating the multielectron reaction kinetics.This work paves a novel strategy for constructing highactivity bifunctional SACs by defect engineering for development of sustainable energy.
基金supported by the BRICS STI Framework Programme(No.52261145703)the Higher Education Discipline Innovation Project(National 111 Project,No.B16016)。
文摘The rational design of Ni-based catalysts is essential due to their abundance and low cost for advancing sustainable energy technologies,particularly for water splitting and fuel cells.This study employs spinpolarized density functional theory(DFT)to examine the influence of anchoring rare-earth elements on the γ-NiOOH lattice surface,aiming to identify the optimal catalytic site for the oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Following the identification of an appropriate active site through Ni vacancy,a rare earth element(REE_(1))is introduced as a dopant for single-atom catalysis(SACs).The structural,thermodynamic,and catalytic characteristics of all newly designed REE_(1)/γ-NiOOH catalysts have been extensively studied.Among the newly developed catalysts,Tb_(1)/γ-NiOOH exhibits the lowest OER overpotential of(0.36 V),while Ce_(1)/γ-NiOOH and Pr_(1)/γ-NiOOH also demonstrate excellent OER performance(0.51 and 0.41 V),respectively.Notably,Nd_(1)/γ-NiOOH and Pm_(1)/γ-NiOOH exhibit efficient ORR activity,with low overpotentials of(0.63 and 0.61 V)due to their balanced adsorption and desorption energies of intermediates.Bader charge analysis reveals strong electron donation from doped REE1to the surface.This study identified Ce_(1),Pr_(1),Nd_(1),and Tb_(1) anchoring catalysts as highly promising for water-splitting applications.Moreover,Nd_(1) and Pm_(1) doping markedly improve ORR performance,underscoring their promise for enhanced electrochemical applications in metal-air batteries.The catalytic performance of all newly developed catalysts was further evaluated using electronic descriptors.The catalytic performance was further assessed using the volcano curve and scaling relationships for the adsorbed intermediates.This study offers an extensive theoretical foundation for designing cost-effective and high-performance REE_(1)/γ-NiOOH electrocatalysts.
基金financially supported by the National Natural Science Foundation of China(51902149,51674131,22305108)the Fundamental Research Funds for Public Universities in Liaoning(LJ232410140033)the Scientific Research Funding of the Education Department of Liaoning Province(JYTZD2023070,LJKFZ20220180,LJKMZ20220453)。
文摘Optimizing active sites and enhancing mass transfer capability are of paramount importance for the improvement of electrocatalyst activity.On this basis,CoFe_(2)O_(4)/CoFe nanoparticles(NPs)loaded N-doped carbon(NC)that featured with interconnected three-dimensional(3D)ordered porous hierarchies(3DOM FeCo/NC)are prepared,and its electrocatalytic activity is studied.Due to the open structure of 3D ordered macro-pores that greatly improves the mass transfer capacity of the catalytic process and enhances the utilization of active sites inside the catalyst,as well as the uniform distribution of Fe and Co bimetallic sites on the porous skeleton,3DOM FeCo/NC exhibits superior bi-functional catalytic activities for both hydrogen evolution reaction(HER)and oxygen reduction reaction(ORR).The overpotential of HER is lower than that of commercial Pt/C when performed at high current density(>235 mA cm^(-2))in1.0 M KOH,and the half-wave potential(0.896 V)of ORR in 0.1 M KOH is also superior to that of 20% commercial Pt/C and most other similar catalysts.The effective utilization and synergistic effect of CoFe_(2)O_(4)and CoFe hetero-metallic sites remarkably enhance the electrocatalytic activity.Furthermore,3DOM FeCo/NC is assembled as an air electrode in Zn-air battery,and exhibits satisfactory maximum power density,open-circuit voltage,and charge/discharge stability over benchmark Pt/C+IrO_(2).This work contributes new insights into the design of transition-metal-based multifunctional catalysts,and has great potential for energy conversion and storage.
基金supported by the National Key Technologies R&D Program of China(Nos.2022YFE0114800 and 2021YFA1502100)National Natural Science Foundation of China(Nos.22075047,22032002,U1905214,21961142019)the 111 Project(Nos.D16008)。
文摘Solar-induced water oxidation reaction(WOR)for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages.WOR is also associated with important reduction reactions,such as oxygen reduction reaction(ORR),which leads to the production of hydrogen peroxide(H_(2)O_(2)).These transitions are instrumental in the emergence and evolution of life.In this study,transition metals were loaded onto nitrogen-doped carbon(NDC)prepared under the primitive Earth's atmospheric conditions.These metal-loaded NDC samples were found to catalyze both WOR and ORR under light illumination.The chemical pathways initiated by the pristine and metal-loaded NDC were investigated.This study provides valuable insights into potential mechanisms relevant to the early evolution of our planet.
