Efficient catalysis of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is essential for the rechargeable zinc-air batteries(R-ZABs).However,challenges remain due to the scarcity of effective bifunc...Efficient catalysis of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is essential for the rechargeable zinc-air batteries(R-ZABs).However,challenges remain due to the scarcity of effective bifunctional electrocatalysts and limited understanding of the structure-activity relationships.Pyrrole-type single-atom catalysts(SACs)with unique electronic structures have emerged as promising electrocatalysts.In this work,we combine density functional theory(DFT)calculations and experimental studies to systematically explore the structure-activity relationships and potential of pyrrole-type transition metal-N_(3)(TM-po-N_(3))as bifunctional catalysts.DFT calculations reveal that differences in the dependence of ORR and OER activities on the free energy of adsorption of reaction intermediates significantly affect the TM-po-N_(3)bifunctional activity and identify magnetic Cu-po-N_(3)as the best candidate.The bifunctional activity of Cu-po-N_(3)originates from interactions between spin-polarized out-of-plane Cu_3d and O_2s+2p orbitals.Theoretical predictions are validated experimentally,showing that the synthesized Cu-SAC/NC exhibits excellent bifunctional performance with a small potential gap of 0.666 V.Additionally,the assembled R-ZABs display a high-power density of 170 mW cm^(-2)and long-term stability,with the charge-discharge voltage gap increasing by only 0.01 V over 240 h.This work provides new insights into the design of efficient bifunctional catalysts.展开更多
Although significant progress has been made in many aspects of the emerging aprotic Li-O2 battery system, an indepth understanding of the oxygen reactions is still underway. The oxygen reactions occurring in the posit...Although significant progress has been made in many aspects of the emerging aprotic Li-O2 battery system, an indepth understanding of the oxygen reactions is still underway. The oxygen reactions occurring in the positive electrode distinguish Li-O2 batteries from the conventional Li-ion cells and play a crucial role in the Li-O2 cell＇s performance （capacity, rate capability, and cycle life）. Recent advances in fundamental studies of oxygen reactions in aprotic Li-O2 batteries are reviewed, including the reaction route, kinetics, morphological evolution of Li2O2, and charge transport within Li2O2. Prospects are also provided for future fundamental investigations of Li-O2 chemistry.展开更多
A theoretical model of chemical and vibrational kinetics of hydrogen oxidation is suggested based on the consistent account for the vibrational nonequilibrium of HO2 radical which forms in result of bimolecular recomb...A theoretical model of chemical and vibrational kinetics of hydrogen oxidation is suggested based on the consistent account for the vibrational nonequilibrium of HO2 radical which forms in result of bimolecular recombination H + O2 = HO2 in the vibrationally excited state. The chain branching H + O2 = O + OH and inhibiting H + O2 + M = HO2 + M formal reactions are considered (in the terms of elementary processes) as a general multi-channel process of forming, intramolecular energy redistribution between modes, relaxation, and monomolecular decay of the comparatively long-lived vibrationally excited HO2 radical which is capable to react and exchange of energy with another components of the mixture. The model takes into account the vibrational nonequilibrium for the starting (primary) H2 and O2 molecules, as well as the most important molecular intermediates HO2, OH, O2(1D), and the main reaction product H2O. The calculated results are compared with the shock tube experimental data for strongly diluted H2-O2 mixtures at 1000 T p < 4 atm. It is demonstrated that this approach is promising from the standpoint of reconciling the predictions of the theoretical model with experimental data obtained by different authors for various compositions and conditions using different methods. It is shown that the hydrogen-oxygen reaction proceeds in absence of vibrational equilibrium, and the vibrationally excited HO2 radical acts as a key intermediate in the principally important chain branching process. For T < 1500 K, the nature of hydrogen-oxygen reaction is especially nonequilibrium, and the vibrational nonequilibrium of HO2 radical is the essence of this process.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
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
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
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
Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nano...Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance.展开更多
Exploiting non-precious metal catalysts with excellent oxygen reduction reaction(ORR)performance for energy devices is paramount essential for the green and sustainable society development.Herein,low-cost,high-perform...Exploiting non-precious metal catalysts with excellent oxygen reduction reaction(ORR)performance for energy devices is paramount essential for the green and sustainable society development.Herein,low-cost,high-performance biomass-derived ORR catalysts with an asymmetric Fe-N_(3)P configuration was prepared by a simple pyrolysis-etching technique,where carboxymethyl cellulose(CMC)was used as the carbon source,urea and 1,10-phenanthroline iron complex(FePhen)as additives,and Na_(3)PO_(4)as the phosphorus dopant and a pore-forming agent.The CMC-derived FeNPC catalyst displayed a large specific area(BET:1235 m^(2)g^(-1))with atomically dispersed Fe-N_(3)P active sites,which exhibited superior ORR activity and stability in alkaline solution(E_(1/2)=0.90 V vs.RHE)and Zn-air batteries(P_(max)=149 mW cm^(-2))to commercial Pt/C catalyst(E_(1/2)=0.87 V,P_(max)=118 mW cm^(-2))under similar experimental conditions.This work provides a feasible and costeffective route toward highly efficient ORR catalysts and their application to Zn-air batteries for energy conversion.展开更多
Nitrogen-doping of carbon support(N-C)for platinum(Pt)nanoparticles to form Pt/N-C catalyst represents an effective strategy to promote the electrocatalysis of cathodic oxygen reduction reaction(ORR)in proton exchange...Nitrogen-doping of carbon support(N-C)for platinum(Pt)nanoparticles to form Pt/N-C catalyst represents an effective strategy to promote the electrocatalysis of cathodic oxygen reduction reaction(ORR)in proton exchange membrane fuel cells.For fundamental understanding,clearly identifying the metalsupport effect on enhancement mechanisms of ORR electrocatalysis is definitely needed.In this work,the impact of Pt-support interaction via interfacial Pt-N coordination on electrocatalytic ORR activity and stability in Pt/N-C catalyst is deeply studied through structural/compositional characterizations,electrochemical measurements and theoretical DFT-calculations/AIMD-simulations.The resulting Pt/N-C catalyst exhibits a superior electrocatalytic performance compared to the commercial Pt/C catalyst in both half-cell and H_(2)-O_(2)fuel cell.Experimental and theoretical results reveal that the interfacial Pt-N coordination enables electron transfer from N-C support to Pt nanoparticles,which can weaken the adsorption strength of oxygen intermediates on Pt surface to improve ORR activity and induce the strong Pt-support interaction to enhance electrochemical stability.展开更多
Selective electrocatalysis of two-electron oxygen reduction reaction(2e^(-)ORR)has been recognized as a sustainable and on-site process for hydrogen peroxide(H_(2)O_(2))production.Great progress has been achieved for ...Selective electrocatalysis of two-electron oxygen reduction reaction(2e^(-)ORR)has been recognized as a sustainable and on-site process for hydrogen peroxide(H_(2)O_(2))production.Great progress has been achieved for 2e^(-)ORR in alkaline media.However,it is challenged by insufficient activity and selectiv-ity of the catalysts in acidic electrolytes.Herein,we report sulfur-poisoned PtNi/C catalysts(PtNiSx/C)that could regulate ORR from the 4e^(-)to 2e^(-)pathway.The identified PtNiS0.6/C offers high activity in terms of onset potential of∼0.69 V(vs.RHE)and∼80%selectivity.The mass activity is also compara-ble and outperforms representative Pt-based precious and transition-metal-based catalysts.In addition,it is interestingly found that the Faradaic efficiency further increased to 95%during the long-term elec-trolysis test due to Ni atom surface migration.The electrochemical production of the H_(2)O_(2)system was applied to the electro-Fenton process,which has realized the effective degradation of organic pollutants.This work offers a strategy by sulfur poisoning PtNi/C catalyst to realize Pt-based 2e^(-)ORR active catalysts to electrolysis of H_(2)O_(2)in acidic media.展开更多
Metal oxohydroxides(MOOH) are widely accepted as the true active species for oxygen evolution reaction(OER).However,the MOOH converted from precatalysts usually exhibits better catalytic performance than those directl...Metal oxohydroxides(MOOH) are widely accepted as the true active species for oxygen evolution reaction(OER).However,the MOOH converted from precatalysts usually exhibits better catalytic performance than those directly synthesized.The underlying structural reason for this phenomenon remains controversial.In this work,CoOOH and Co(OH)2with similar morphology are employed as model catalysts to investigate the origin of in-situ converted catalyst s high activity,as Co(OH)2can be fully converted to CoOOH during OER.In-situ Raman,electron paramagnetic resonance,HR-TEM,and X-ray spectroscopic studies reveal that O vacancies in the CoOOH converted from Co(OH)2play a key role in its higher intrinsic activity towards OER than directly synthesized CoOOH.Furthermore,theoretical calculations and electrochemical methods indicate that O vacancies in CoOOH affect the interaction between Co-O bond,downshift the d-band center of Co,further weaken the adsorption of OH*,and finally facilitate the OER process over CoOOH.This work not only provides a deep understanding of pre-catalyst's high OER activity by taking Co(OH)2as an example but also deliver insights into the activation process of other electrochemic al oxidation reactions.展开更多
基金supported by the Hainan Province Science and Technology Special Fund(ZDYF2020037)the National Natural Science Foundation of China(22109035,52164028,52274297,22462006)+3 种基金the Postdoctoral Science Foundation of Hainan Province(RZ2100007123)the Basic and Applied Basic Research Foundation of Guangdong Province(2019A1515110558)the Start-up Research Foundation of Hainan University(KYQD(ZR)-20008,20083,20084,21125)Hainan University(XTCX2022HYC05)。
文摘Efficient catalysis of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is essential for the rechargeable zinc-air batteries(R-ZABs).However,challenges remain due to the scarcity of effective bifunctional electrocatalysts and limited understanding of the structure-activity relationships.Pyrrole-type single-atom catalysts(SACs)with unique electronic structures have emerged as promising electrocatalysts.In this work,we combine density functional theory(DFT)calculations and experimental studies to systematically explore the structure-activity relationships and potential of pyrrole-type transition metal-N_(3)(TM-po-N_(3))as bifunctional catalysts.DFT calculations reveal that differences in the dependence of ORR and OER activities on the free energy of adsorption of reaction intermediates significantly affect the TM-po-N_(3)bifunctional activity and identify magnetic Cu-po-N_(3)as the best candidate.The bifunctional activity of Cu-po-N_(3)originates from interactions between spin-polarized out-of-plane Cu_3d and O_2s+2p orbitals.Theoretical predictions are validated experimentally,showing that the synthesized Cu-SAC/NC exhibits excellent bifunctional performance with a small potential gap of 0.666 V.Additionally,the assembled R-ZABs display a high-power density of 170 mW cm^(-2)and long-term stability,with the charge-discharge voltage gap increasing by only 0.01 V over 240 h.This work provides new insights into the design of efficient bifunctional catalysts.
基金supported by the Recruitment Program of Global Youth Experts of Chinathe Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA09010401)+1 种基金the Science and Technology Development Program of Jilin Province,China(Grant No.20150623002TC)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20131139)
文摘Although significant progress has been made in many aspects of the emerging aprotic Li-O2 battery system, an indepth understanding of the oxygen reactions is still underway. The oxygen reactions occurring in the positive electrode distinguish Li-O2 batteries from the conventional Li-ion cells and play a crucial role in the Li-O2 cell＇s performance （capacity, rate capability, and cycle life）. Recent advances in fundamental studies of oxygen reactions in aprotic Li-O2 batteries are reviewed, including the reaction route, kinetics, morphological evolution of Li2O2, and charge transport within Li2O2. Prospects are also provided for future fundamental investigations of Li-O2 chemistry.
文摘A theoretical model of chemical and vibrational kinetics of hydrogen oxidation is suggested based on the consistent account for the vibrational nonequilibrium of HO2 radical which forms in result of bimolecular recombination H + O2 = HO2 in the vibrationally excited state. The chain branching H + O2 = O + OH and inhibiting H + O2 + M = HO2 + M formal reactions are considered (in the terms of elementary processes) as a general multi-channel process of forming, intramolecular energy redistribution between modes, relaxation, and monomolecular decay of the comparatively long-lived vibrationally excited HO2 radical which is capable to react and exchange of energy with another components of the mixture. The model takes into account the vibrational nonequilibrium for the starting (primary) H2 and O2 molecules, as well as the most important molecular intermediates HO2, OH, O2(1D), and the main reaction product H2O. The calculated results are compared with the shock tube experimental data for strongly diluted H2-O2 mixtures at 1000 T p < 4 atm. It is demonstrated that this approach is promising from the standpoint of reconciling the predictions of the theoretical model with experimental data obtained by different authors for various compositions and conditions using different methods. It is shown that the hydrogen-oxygen reaction proceeds in absence of vibrational equilibrium, and the vibrationally excited HO2 radical acts as a key intermediate in the principally important chain branching process. For T < 1500 K, the nature of hydrogen-oxygen reaction is especially nonequilibrium, and the vibrational nonequilibrium of HO2 radical is the essence of this process.
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support from the National Natural Science Foundation of China(Nos.12305373 and 52276220)the Guangzhou Basic Research Program(No.SL2024A04J00234).
文摘Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies.
基金supported by 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.
文摘Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance.
基金supported by the National Natural Science Foundation of China(No.21571062)the Program for Professor of Special Appointment(Eastern Scholar)at the Shanghai Institutions of Higher Learning to JGL,and the Fundamental Research Funds for the Central Universities(No.222201717003)。
文摘Exploiting non-precious metal catalysts with excellent oxygen reduction reaction(ORR)performance for energy devices is paramount essential for the green and sustainable society development.Herein,low-cost,high-performance biomass-derived ORR catalysts with an asymmetric Fe-N_(3)P configuration was prepared by a simple pyrolysis-etching technique,where carboxymethyl cellulose(CMC)was used as the carbon source,urea and 1,10-phenanthroline iron complex(FePhen)as additives,and Na_(3)PO_(4)as the phosphorus dopant and a pore-forming agent.The CMC-derived FeNPC catalyst displayed a large specific area(BET:1235 m^(2)g^(-1))with atomically dispersed Fe-N_(3)P active sites,which exhibited superior ORR activity and stability in alkaline solution(E_(1/2)=0.90 V vs.RHE)and Zn-air batteries(P_(max)=149 mW cm^(-2))to commercial Pt/C catalyst(E_(1/2)=0.87 V,P_(max)=118 mW cm^(-2))under similar experimental conditions.This work provides a feasible and costeffective route toward highly efficient ORR catalysts and their application to Zn-air batteries for energy conversion.
基金supported by the National Natural Science Foundation of China(Nos.22272105 and 22002110)Natural Science Foundation of Shanghai(No.23ZR1423900)。
文摘Nitrogen-doping of carbon support(N-C)for platinum(Pt)nanoparticles to form Pt/N-C catalyst represents an effective strategy to promote the electrocatalysis of cathodic oxygen reduction reaction(ORR)in proton exchange membrane fuel cells.For fundamental understanding,clearly identifying the metalsupport effect on enhancement mechanisms of ORR electrocatalysis is definitely needed.In this work,the impact of Pt-support interaction via interfacial Pt-N coordination on electrocatalytic ORR activity and stability in Pt/N-C catalyst is deeply studied through structural/compositional characterizations,electrochemical measurements and theoretical DFT-calculations/AIMD-simulations.The resulting Pt/N-C catalyst exhibits a superior electrocatalytic performance compared to the commercial Pt/C catalyst in both half-cell and H_(2)-O_(2)fuel cell.Experimental and theoretical results reveal that the interfacial Pt-N coordination enables electron transfer from N-C support to Pt nanoparticles,which can weaken the adsorption strength of oxygen intermediates on Pt surface to improve ORR activity and induce the strong Pt-support interaction to enhance electrochemical stability.
基金financially supported by the National Natu-ral Science Foundation of China(Nos.21805052 and 22227804)the Guangdong Basic and Applied Basic Research Foundation(No.2023B1515020110)+4 种基金the Science and Technology Research Project of Guangzhou(Nos.202102020787 and 2023A03J0030)the De-partment of Science&Technology of Guangdong Province(No.2022A156)the Key Laboratory of Optoelectronic Materials and Sensors in Guangdong Provincial Universities(No.2023KSYS008)the Key Discipline of Materials Science and Engineering,Bureau of Education of Guangzhou(No.20225546)the College Student Innovation and Entrepreneurship Training Program of Guangzhou University(No.XJ202311078029).
文摘Selective electrocatalysis of two-electron oxygen reduction reaction(2e^(-)ORR)has been recognized as a sustainable and on-site process for hydrogen peroxide(H_(2)O_(2))production.Great progress has been achieved for 2e^(-)ORR in alkaline media.However,it is challenged by insufficient activity and selectiv-ity of the catalysts in acidic electrolytes.Herein,we report sulfur-poisoned PtNi/C catalysts(PtNiSx/C)that could regulate ORR from the 4e^(-)to 2e^(-)pathway.The identified PtNiS0.6/C offers high activity in terms of onset potential of∼0.69 V(vs.RHE)and∼80%selectivity.The mass activity is also compara-ble and outperforms representative Pt-based precious and transition-metal-based catalysts.In addition,it is interestingly found that the Faradaic efficiency further increased to 95%during the long-term elec-trolysis test due to Ni atom surface migration.The electrochemical production of the H_(2)O_(2)system was applied to the electro-Fenton process,which has realized the effective degradation of organic pollutants.This work offers a strategy by sulfur poisoning PtNi/C catalyst to realize Pt-based 2e^(-)ORR active catalysts to electrolysis of H_(2)O_(2)in acidic media.
基金financially supported by the financial support from Natural Science Foundation of China(No.22209129)the High-Level Innovation and Entrepreneurship Talent Project of Qinchuangyuan(No.QCYRCXM-2022-123)+3 种基金the Innovation Capability Support Program of Shaanxi(No.2023-CXTD-26)the financial support from the"Young Talent Support Plan''of Xi'an Jiaotong University(No.HG6J024)the financial support from China Postdoctoral Science Foundation 2024M752560Postdoctoral Fellowship Program of CPSF under Grant Number GZB20230574
文摘Metal oxohydroxides(MOOH) are widely accepted as the true active species for oxygen evolution reaction(OER).However,the MOOH converted from precatalysts usually exhibits better catalytic performance than those directly synthesized.The underlying structural reason for this phenomenon remains controversial.In this work,CoOOH and Co(OH)2with similar morphology are employed as model catalysts to investigate the origin of in-situ converted catalyst s high activity,as Co(OH)2can be fully converted to CoOOH during OER.In-situ Raman,electron paramagnetic resonance,HR-TEM,and X-ray spectroscopic studies reveal that O vacancies in the CoOOH converted from Co(OH)2play a key role in its higher intrinsic activity towards OER than directly synthesized CoOOH.Furthermore,theoretical calculations and electrochemical methods indicate that O vacancies in CoOOH affect the interaction between Co-O bond,downshift the d-band center of Co,further weaken the adsorption of OH*,and finally facilitate the OER process over CoOOH.This work not only provides a deep understanding of pre-catalyst's high OER activity by taking Co(OH)2as an example but also deliver insights into the activation process of other electrochemic al oxidation reactions.
