Utilizing nitrate(NO_(3)^(-))as the nitrogen source to produce ammonia can effectively remove NO_(3)^(-)pollutant while obtaining valuable ammonia,and the understanding of the mechanisms is essential for the design of...Utilizing nitrate(NO_(3)^(-))as the nitrogen source to produce ammonia can effectively remove NO_(3)^(-)pollutant while obtaining valuable ammonia,and the understanding of the mechanisms is essential for the design of new catalysts.In this work,by using density functional theory calculations,the electroreduction mechanisms of nitrate reduction reaction(NO_(3)RR)on transition metal single atom supported on 3N-coordinated N-doped graphene(TM/N_(3)-G)are systematically investigated.It is found that the protonation of ^(*)OH acts as the potential determing steps except for the traditionally considered ^(*)NO_(3)/^(*)NO/^(*)NO_(2) protonation step and the desorption of water may play an important role for NO_(3)RR on some TM/N_(3)-G.By considering the stability of single-atom catalyst(SAC),the preferential adsorption of NO_(3)^(-)larger than H and H_(2)O,the limiting potential of whole NO_(3)RR,the selectivity toward NH3,V(Mn,Os)/pyrrolic-N_(3)-G and Mn(Ru,Ir)/pyridinic-N_(3)-G are screened out as potential SACs for NO_(3)RR.This work provides an understanding of the NO_(3)RR mechanism and highlights several promising NO_(3)RR catalysts based on the TM/N_(3)-G system.展开更多
Developing efficient electrocatalysts for the nitrate reduction reaction(NIRR)to ammonia is vital for environmental remediation and sustainable ammonia synthesis.Metal-oxide-based single-atom catalysts(SACs)offer atom...Developing efficient electrocatalysts for the nitrate reduction reaction(NIRR)to ammonia is vital for environmental remediation and sustainable ammonia synthesis.Metal-oxide-based single-atom catalysts(SACs)offer atomic-scale efficiency,yet unclear anchoring strategies for single metal sites hinder their rational design.This study systematically explored the effects of surface-loading and latticedoping strategies on anchoring transition,rare-earth,and main-group metal atoms onto Co_(3)O_(4)via the synergy of machine learning and density functional theory calculations.Through a comprehensive assessment of stability,catalytic activity,and electronic structures,it is discovered that lattice-doping enhances SACs stability by firmly anchoring metal atoms on Co sites,while surface-loading significantly boosts catalytic activity for the NIRR.Calculations predicted that Al,Ir,Rh,and Mo sites anchored through the surface-loading strategy exhibited exceptional NIRR activity(the limiting potential for Al site can reaches-0.25 V versus the reversible hydrogen electrode),far surpassing many other configurations.To further decipher the underlying mechanisms,the machine learning algorithms,especially the treebased pipeline optimization tool model,revealed that SACs activity is highly correlated with the local environment of the active center,particularly its electronic and structural characteristics.This work establishes a new design paradigm for SACs,providing both theoretical guidelines for anchoring strategy selection and a predictive framework for efficient NIRR electrocatalysts.展开更多
Electrocatalytic nitrate-to-ammonia conversion offers dual environmental and sustainable synthesis benefits,but achieving high efficiency with low-cost catalysts remains a major challenge.This review focuses on cobalt...Electrocatalytic nitrate-to-ammonia conversion offers dual environmental and sustainable synthesis benefits,but achieving high efficiency with low-cost catalysts remains a major challenge.This review focuses on cobalt-based electrocatalysts,emphasizing their structural engineering for enhanced the performance of electrocatalytic nitrate reduction reaction(NO3RR)through dimensional control,compositional tuning,and coordination microenvironment modulation.Notably,by critically analyzing metallic cobalt,cobalt alloys,cobalt compounds,cobalt single atom and molecular catalyst configurations,we firstly establish correlations between atomic-scale structural features and catalytic performance in a coordination environment perspective for NO3RR,including the dynamic reconstruction during operation and its impact on active site.Synergizing experimental breakthroughs with computational modeling,we decode mechanisms underlying competitive hydrogen evolution suppression,intermediate adsorption-energy optimization,and durability enhancement in complex aqueous environments.The development of cobalt-based catalysts was summarized and prospected,and the emerging opportunities of machine learning in accelerating the research and development of high-performance catalysts and the configuration of series reactors for scalable nitrate-to-ammonia systems were also introduced.Bridging surface science and applications,it outlines a framework for designing multifunctional electrocatalysts to restore nitrogen cycle balance sustainably.展开更多
Direct electrochemical nitrate reduction reaction(NITRR)is a promising strategy to alleviate the unbalanced nitrogen cycle while achieving the electrosynthesis of ammonia.However,the restructuration of the high-activi...Direct electrochemical nitrate reduction reaction(NITRR)is a promising strategy to alleviate the unbalanced nitrogen cycle while achieving the electrosynthesis of ammonia.However,the restructuration of the high-activity Cu-based electrocatalysts in the NITRR process has hindered the identification of dynamical active sites and in-depth investigation of the catalytic mechanism.Herein,Cu species(single-atom,clusters,and nanoparticles)with tunable loading supported on N-doped TiO_(2)/C are successfully manufactured with MOFs@CuPc precursors via the pre-anchor and post-pyrolysis strategy.Restructuration behavior among Cu species is co-dependent on the Cu loading and reaction potential,as evidenced by the advanced operando X-ray absorption spectroscopy,and there exists an incompletely reversible transformation of the restructured structure to the initial state.Notably,restructured CuN_(4)&Cu_(4) deliver the high NH_(3) yield of 88.2 mmol h^(−1)g_(cata)^(−1) and FE(~94.3%)at−0.75 V,resulting from the optimal adsorption of NO_(3)^(−) as well as the rapid conversion of^(*)NH_(2)OH to^(*)NH_(2) intermediates originated from the modulation of charge distribution and d-band center for Cu site.This work not only uncovers CuN_(4)&Cu_(4) have the promising NITRR but also identifies the dynamic Cu species active sites that play a critical role in the efficient electrocatalytic reduction in nitrate to ammonia.展开更多
The accumulation of excessive nitrate in the atmosphere not only jeopardizes human health but also disrupts the balance of the nitrogen cycle in the ecosystem.Among various nitrate removal technologies,electrocatalyti...The accumulation of excessive nitrate in the atmosphere not only jeopardizes human health but also disrupts the balance of the nitrogen cycle in the ecosystem.Among various nitrate removal technologies,electrocatalytic nitrate reduction reaction(eNO_(3)RR)has been widely studied for its advantages of being eco-friendly,easy to operate,and controllable under environmental conditions with renewable energy as the driving force.Transition metal-based catalysts(TMCs)have been widely used in electrocatalysis due to their abundant reserves,low costs,easy-to-regulate electronic structure and considerable electrochemical activity.In addition,TMCs have been extensively studied in terms of the kinetics of the nitrate reduction reaction,the moderate adsorption energy of nitrogen-containing species and the active hydrogen supply capacity.Based on this,this review firstly discusses the mechanism as well as analyzes the two main reduction products(N_(2)and NH_(3))of eNO_(3)RR,and reveals the basic guidelines for the design of efficient nitrate catalysts from the perspective of the reaction mechanism.Secondly,this review mainly focuses on the recent advances in the direction of eNO_(3RR)with four types of TMCs,Fe,Co,Ni and Cu,and unveils the interfacial modulation strategies of Fe,Co,Ni and Cu catalysts for the activity,reaction pathway and stability.Finally,reasonable suggestions and opportunities are proposed for the challenges and future development of eNO_(3)RR.This review provides far-reaching implications for exploring cost-effective TMCs to replace high-cost noble metal catalysts(NMCs)for eNO_(3)RR.展开更多
Mass transfer can tune the surface concentration of reactants and products and subsequently infl uence the catalytic perfor-mance.The morphology of nanomaterials plays an important role in the mass transfer of reactio...Mass transfer can tune the surface concentration of reactants and products and subsequently infl uence the catalytic perfor-mance.The morphology of nanomaterials plays an important role in the mass transfer of reaction microdomains,but related studies are lacking.Herein,a facile electrospinning technique utilizing cellulose was employed to fabricate a series of carbon nanofi bers with diff erent diameters,which exhibited excellent electrochemical nitrate reduction reaction and oxygen evolu-tion reaction activities.Furthermore,the microstructure of electrocatalysts could infl uence the gas-liquid-solid interfacial mass transfer,resulting in diff erent electrochemical performances.展开更多
Ammonia is the cornerstone of modern agriculture,providing a critical nitrogen source for global food production and serving as a key raw material for numerous industrial chemicals.Electrocatalytic nitrate reduction,a...Ammonia is the cornerstone of modern agriculture,providing a critical nitrogen source for global food production and serving as a key raw material for numerous industrial chemicals.Electrocatalytic nitrate reduction,as an environmentally friendly method for synthesizing ammonia,not only mitigates the reliance on current ammonia synthesis processes fed by traditional fossil fuels but also effectively reduces nitrate pollution resulting from agricultural and industrial activities.This review explores the fundamental principles of electrocata lytic nitrate reduction,focusing on the key steps of electron transfer and ammonia formation.Additionally,it summarizes the critical factors influencing the performance and selectivity of the reaction,including the properties of the electrolyte,operating voltage,electrode materials,and design of the electrolytic cell.Further discussion of recent advances in electrocatalysts,including pure metal catalysts,metal oxide catalysts,non-metallic catalysts,and composite catalysts,highlights their significant roles in enhancing both the efficiency and selectivity of electrocata lytic nitrate to ammonia(NRA)reactions.Critical challenges for the industrial NRA trials and further outlooks are outlined to propel this strategy toward real-world applications.Overall,the review provides an in-depth overview and comprehensive understanding of electrocata lytic NRA technology,thereby promoting further advancements and innovations in this domain.展开更多
Zinc-nitrate battery could produce electrical power,remove pollutant nitrate and obtain value-added ammonia,where the cathodic reaction of converting nitrate to ammonia is sluggish and complex due to the involvement o...Zinc-nitrate battery could produce electrical power,remove pollutant nitrate and obtain value-added ammonia,where the cathodic reaction of converting nitrate to ammonia is sluggish and complex due to the involvement of multi-electron transfer.Thus,highly efficient catalysts for nitrate reduction reaction(NO_(3)RR)are greatly needed.In this work,we report a high entropy hydroxide(HE-OH)as an excellent NO3RR catalyst,which could achieve high NH_(3)Faradaic efficiencies(e.g.,nearly 100%at-0.3 V versus reversible hydrogen electrode)and high yield rates(e.g.,30.4 mg h^(-1)cm^(-2)at-0.4 V).Moreover,HE-OH could also deliver a current density of 10 mA/cm^(2) at an overpotential of 260 mV for oxygen evolution reaction.The assembled zinc-nitrate battery using HE-OH as the cathode demonstrates a high power density(e.g.,3.62 mW/cm^(2)),rechargeability and stability.展开更多
The electrochemical nitrate reduction reaction(NO_(3)^(-)RR)represents a promising and environmentally friendly approach for both the removal of nitrate(NO_(3)^(-))pollutants and the production of high-value ammonia(N...The electrochemical nitrate reduction reaction(NO_(3)^(-)RR)represents a promising and environmentally friendly approach for both the removal of nitrate(NO_(3)^(-))pollutants and the production of high-value ammonia(NH_(3)).However,this process faces significant challenges in achieving industrial application due to mismatched reaction kinetics involved in the conversion of NO_(3)^(-)to NO_(2)^(-),the formation of active hydrogen(H^(*))via water dissociation,and the stepwise hydrogenation processes.In this study,we developed a trimetallic CuCoRu catalyst with multiple active sites to enhance the selective NH_(3)synthesis at industrial-scale current density,where Cu primarily catalyzes the reduction of NO_(3)^(-)to NO_(2)^(-),Co facilitates the deep hydrogenation of NO_(2)^(-)to NH_(3),and Ru promotes water dissociation to generate H^(*),effectively bridging the aforementioned processes.The optimized CuCoRu catalyst achieves near-100%NH_(3)Faradaic efficiency with an NH_(3)yield rate of 14.6 mmol h^(-1)cm^(-2)at a current density of 2.5 A cm^(-2).The practical application in simulated wastewater with different NO_(3)^(-)concentrations and in the membrane electrode assembly demonstrates great potential for industrial application.展开更多
Electrochemical nitrate(NO_(3)^(-))reduction reaction(eNO_(3)RR)presents a promising and sustainable strategy for converting environmentally hazardous NO_(3)^(-)into value-added ammonia(NH3),thereby addressing both po...Electrochemical nitrate(NO_(3)^(-))reduction reaction(eNO_(3)RR)presents a promising and sustainable strategy for converting environmentally hazardous NO_(3)^(-)into value-added ammonia(NH3),thereby addressing both pollution mitigation and nitrogen resource recovery.However,its practical implementation remains hindered by the limited availability of electrocatalysts that simultaneously offer high activity,selectivity,and stability.In this study,we systematically investigate the catalytic potential of 300 Cu-based heteronuclear trimetallic dual-atom alloys(DAAs),featuring heterometallic dual-atom active sites embedded on a catalytically suboptimal Cu(111)surface.By combining high-throughput firstprinciples calculations with a hierarchical four-step screening strategy,we efficiently identify promising DAA catalysts for eNO_(3)RR.Among them,CrRh and MnRh catalysts stand out,exhibiting ultralow limiting potentials of-0.16 and-0.25 V,respectively,along with excellent selectivity and stability.Constantpotential simulations further reveal that both catalysts maintain high activity and selectivity across varying pH conditions and applied potentials.Geometric and electronic structure analyses indicate that the incorporation of dual-atom sites induces local lattice distortion and charge polarization,effectively tuning the electronic structure of the active centers.Notably,strong d-d orbital interactions between the embedded metal dimers give rise to new molecule-like electronic states near the Fermi level.These states facilitate effective activation of NO_(3)^(-)and NO via an electron“acceptance-donation”mechanism,driven by p-d orbital interactions between adsorbates and metal dimers.This work not only strategically designs efficient heteronuclear Cu-based DAA catalysts but also provides valuable insights into the electronic synergistic effects of dual-atom sites in modulating eNO_(3)RR performance.It establishes a promising platform for demonstrating the feasibility of constructing dual-atom active centers on pure metal surfaces for eNO_(3)RR,while broadening the potential applications of DAAs in electrocatalysis and related fields.展开更多
Mild electrocatalytic nitrate reduction reaction(NO_(3)RR),driven by renewable electricity,is regarded as a desirable strategy for green ammonia synthesis and simultaneous removal of nitrogen-containing environmental ...Mild electrocatalytic nitrate reduction reaction(NO_(3)RR),driven by renewable electricity,is regarded as a desirable strategy for green ammonia synthesis and simultaneous removal of nitrogen-containing environmental pollutants.In view of different supply voltages from renewable energy sources,developing costeffective and efficient electrocatalysts with a wide operating potential window is very meaningful for practical application.However,currently reported catalysts usually need to introduce noble metals to synergistically achieve wide-potential selective ammonia synthesis from nitrate.In this work,we present for the first time a dual-transition-metal electrocatalyst(Fe_(3)C-CuO_(x)@NC,x=0,1)with wide-potential-adaptability for highly selective nitrate reduction to ammonia.Such Fe_(3)C-CuO_(x)@NC with spatially separated CuO_(x)and noblemetal-like Fe_(3)C nanoparticles encapsulated with nitrogen-doped graphitized carbon,exhibits outstanding performance in NO_(3)RR with desirable NH_(3)Faraday efficiency of more than 90%over a wide potential ranging from-0.2 V vs.RHE to-0.6 V vs.RHE,comparable to the reported noble metal catalysts.Different from common tandem catalysis,the wide-potential high ammonia selectivity of Fe_(3)C-CuO_(x)@NC is domina ntly ascribed to the complementary enhancement between CuO_(x)and Fe_(3)C,fully supported by results of experiments and density function theory calculations.CuO_(x)exhibit highly intrinsic nitrate reduction to nitrite to compensate for the slow potential determination step(^(*)NO_(3)→^(*)NO_(3)H)of Fe_(3)C,while Fe_(3)C,besides behaving like noble metals to supply adequate active hydrogens,has both good adsorption and reduction abilities for nitrite species to ammonia.Moreover,Fe_(3)C partially stabilizes active Cu^(0)/Cu^(+)sites,and the unique carbon-layer enca psulation structure effectively prevents the agglomeration and corrosion of metal nanoparticles during the electrocatalysis,thus maintaining good cyclic stability.The Zn-NO_(3)^(-)battery assembled with Fe_(3)C-CuO_(x)@NC can reach a high power density of 5.2 mW cm^(-2)at a potential of 1.0 V vs.Zn,with an NH_(3)Faraday efficiency of 92.4%at a current of 8.0 mA,proving its potential practical application.This advance provides unique insights into complementary catalysis mechanisms on multiple metal sites in NO_(3)RR,and offers a reference for the design of other transition metal electrocatalysts matching with renewable electricity.展开更多
Electrochemical reduction reactions,including the oxygen reduction reaction(ORR),hydrogen evolution reaction(HER),carbon dioxide reduction reaction(CRR),and nitrate reduction reaction(NRR),hold promise for energy conv...Electrochemical reduction reactions,including the oxygen reduction reaction(ORR),hydrogen evolution reaction(HER),carbon dioxide reduction reaction(CRR),and nitrate reduction reaction(NRR),hold promise for energy conversion and storage.However,electrocatalysts exhibit slow kinetics and inactivation effects,resulting in inadequate energy efficiency and poor stability.To address these challenges,the groupⅧelement-based single-atom electrocatalysts(GVSAEs)were endowed with tunable electronic structures and porous carbon substrates to reduce intermediate adsorption and desorption energy barriers,which can accelerate electrochemical kinetics.This mini review summarises the recent achievements in GVSAEs with electronic structure and porous substrate engineering discussions.Furthermore,these GVSAEs are divided into non-noble iron series element(Fe,Co,and Ni)single-atom electrocatalysts and noble platinum series elements(Ru,Rh,Pd,Os,Ir,and Pt)based single-atom electrocatalysts for the ORR,HER,CRR,and NRR,where the porous substrate structure,electronic structure,and catalytic activity are discussed.Finally,conclusions and perspectives relating to future challenges and potential opportunities are provided for electrocatalysis with better performance.展开更多
Atomically precise copper-based nanoclusters stand out as one of the highly promising catalysts in the realm of electrochemical nitrate reduction reaction(NITRR)aimed at ammonia(NH_(3))synthesis.However,the controllab...Atomically precise copper-based nanoclusters stand out as one of the highly promising catalysts in the realm of electrochemical nitrate reduction reaction(NITRR)aimed at ammonia(NH_(3))synthesis.However,the controllable synthesis of stable Cu-based nanoclusters featuring fully inorganic anionic ligands for electrochemical NITRR remains a challenge.Herein,we present a simple and gentle chelated co-precipitation method for the uniform growth of ultrafine amorphous Cu(OH)Cl(a-Cu(OH)Cl)nanoclusters,featuring a diameter of approximately 9 nm,onto carbon nanotubes(a-Cu(OH)Cl/CNTs),aimed at enhancing electrocatalytic NITRR performance.Intriguingly,trisodium citrate dihydrate(TCD)could effectively change the crystalline form of Cu-based nanoclusters to obtain a-Cu(OH)Cl nanoclusters instead of high-crystallinity Cu_(2)(OH)_(3)Cl(c-Cu_(2)(OH)_(3)Cl)nanoclusters.In comparison to c-Cu_(2)(OH)_(3)Cl nanoclusters,a-Cu(OH)Cl nanoclusters,featuring a smaller particle size and containing more lowcoordination Cu atoms,provide more efficient catalytic sites,thereby enhancing the reaction rate and energy efficiency for NH_(3)production.The proposed chelated co-precipitation method provides a promising crystalline modulation engineering strategy to boost the electrocatalytic performances of metal nanoclusters.展开更多
In this work,an effective catalyst of Cu/MnOOH has been successfully constructed for electrochemical nitrate reduction reaction(e NO_(3)RR)for synthesis of ammonia(NH_(3))under ambient conditions.The substrate of MnOO...In this work,an effective catalyst of Cu/MnOOH has been successfully constructed for electrochemical nitrate reduction reaction(e NO_(3)RR)for synthesis of ammonia(NH_(3))under ambient conditions.The substrate of MnOOH plays an important role on the size and electronic structure of Cu nanoparticles,where Cu has the ultrafine size of 2.2 nm and positive shift of its valence states,which in turn causes the increased number of Cu active sites and enhanced intrinsic activity of every active site.As a result,this catalyst realizes an excellent catalytic performance on eNO_(3)RR with the maximal NH_(3)Faraday efficiency(FE)(96.8%)and the highest yield rate(55.51 mg h^(-1)cm^(-2))at a large NH_(3)partial current density of700 m A/cm^(2),which could help to promote the industrialization of NH_(3)production under ambient conditions.展开更多
In this paper we report the preparation of nano-dendritic Cu_(2)O/Cu heterojunctions doped with varying concentrations of cobalt through a convenient,energy-consumption-free,and environmentally friendly chemical repla...In this paper we report the preparation of nano-dendritic Cu_(2)O/Cu heterojunctions doped with varying concentrations of cobalt through a convenient,energy-consumption-free,and environmentally friendly chemical replacement method.The analysis results reveal that the incorporation of cobalt in its atomic form enhances the adsorption of nitrate species onto the catalyst surface,whereas doping with metallic cobalt promotes the production of active hydrogen(*H).By adjusting the doping concentration of cobalt,we effectively control its doping form(atomic and metallic states)on the surface of dendritic copper,thereby enabling controllable modulation of the active hydrogen concentration on the catalyst surface.By ensuring sufficient consumption of*H during the NITRR process while avoiding excessively high concentrations that could trigger detrimental hydrogen evolution reaction side reactions,this approach remarkably enhances the selectivity of ammonia synthesis in NITRR.This study offers an effective approach to regulate the*H concentration on the surface of the catalyst through adjusting the metal doping form,thereby improving the performance of ammonia synthesis from NITRR.展开更多
Modulating the adsorption energy of intermediate species via alloying presents a promising approach to enhance the electrocatalytic nitrate reduction to ammonia(NRA).Nonetheless,the synthesis of alloy catalysts that a...Modulating the adsorption energy of intermediate species via alloying presents a promising approach to enhance the electrocatalytic nitrate reduction to ammonia(NRA).Nonetheless,the synthesis of alloy catalysts that are uniformly distributed and structurally stable poses significant challenges.Herein,the CuNi alloy was successfully anchored on oxygen vacancy-rich N-Ti_(3)C_(2)T_(x) through metal-support interactions(MSI).The three-dimensional(3D)wrinkled morphology of N-Ti_(3)C_(2)T_(x) MXene was achieved by employing melamine-formaldehyde spheres(MFs)as self-sacrificial templates,which effectively prevented the restacking of the Ti_(3)C_(2)T_(x) layers,thereby increasing specific surface area and promoting the formation of surface oxygen vacancies.Ti–O–M structure plays a crucial role in inhibiting both particle migration and metal atom diffusion.X-ray photoelectron spectroscopy(XPS)analysis confirms moderate metal-support interactions between the CuNi alloy and N-Ti_(3)C_(2)T_(x),leading to the establishment of stable Ti–O–M bonds and charge redistribution within the Ti-O-M framework.The Cu_(5)Ni_(5)/N-Ti_(3)C_(2)T_(x) sample achieves an impressive Faradaic efficiency(FE)of 97.50%at−0.27 V vs.RHE,alongside the highest NH3 yield rate of 527.44µmol h−1 cm−2.In-situ electrochemical Raman spectroscopy and theoretical calculations reveal that the high intrinsic catalytic activity of NRA can be attributed to the synergistic effects between the CuNi alloy and the interfacial metal-oxygen interactions.This work provides significant perspectives on the design of interfacial metal interactions and the development of durable electrocatalysts.展开更多
A novel Cu-t-ZrO_(2)catalyst with enhanced electronic metal-support interaction(EMSI)is designed for efficient electrocatalytic conversion of nitrate(NO_(3^(-)))to ammonia(NH_(3)),achieving a remarkable Faradaic effic...A novel Cu-t-ZrO_(2)catalyst with enhanced electronic metal-support interaction(EMSI)is designed for efficient electrocatalytic conversion of nitrate(NO_(3^(-)))to ammonia(NH_(3)),achieving a remarkable Faradaic efficiency and yield rate of 97.54%and 33.64 mg h^(-1)mg_(cat)^(-1),respectively.Electrons are more likely to be transferred from Cu to t-ZrO_(2)at the electron-rich interface due to the lower work function,which promotes the formation of highly active Cu species and facilitates NO_(3^(-))adsorption,ensuring selective conversion into NH_(3).展开更多
Electrochemical nitrate(NO_(3)^(-))reduction reaction(eNO_(3)RR)to ammonia(NH3)provides a promising route for both water conservation and green ammonia synthesis.Although various catalysts were designed for the eNO_(3...Electrochemical nitrate(NO_(3)^(-))reduction reaction(eNO_(3)RR)to ammonia(NH3)provides a promising route for both water conservation and green ammonia synthesis.Although various catalysts were designed for the eNO_(3)RR and great achievements have been achieved,it is still a challenge to realize selective eNO_(3)RR to NH3at low concentration for the competing hydrogen evolution reaction(HER)and poor mass transfer of NO_(3)^(-).Herein,we designed a tandem catalyst of Pd nanoparticle loaded Cu_(2)O hierarchical nanofiber(Pd-Cu_(2)O)to improve eNO_(3)RR performance at low nitrate concentration.The Pd-Cu_(2)O shows a faraday efficiency(FE)of 95.80%and an ammonia selectivity of 97.34%at a comparatively low applied potential of-0.15 V versus RHE with low concentration.Besides,it exhibits excellent nitrate removal effects,the residual concentration of nitrate-N was only 7.22 ppm at-0.15 V.Electrochemical characterizations indicate that the abundant secondary heterojunction structures and the tandem effects of Pd-Cu_(2)O synergistic ally accelerate the transfer and conversion of NO_(3)^(-)and improve the dynamic of eNO_(3)RR at low concentration.Furthermore,the operando electrochemical impedance spectroscopy(EIS)and density functional theory(DFT)calculations suggested the tandem effects of Pd-Cu_(2)O improved the adsorption of NO_(3)^(-)and*H and thus promoted the dynamics of eNO_(3)RR at low concentration.The findings highlight the tandem effects of Pd-Cu_(2)O and provide an effective strategy for designing electrocatalysts that can be applied to low concentration and low applied potential conditions.展开更多
In vitro antioxidant activities of resveratrol and piceid against peroxynitrite（ONOO-） were examined by the inhibition of 3-nitrotyrosine formation.Trolox was used as a positive control.Resveratrol and piceid exhibi...In vitro antioxidant activities of resveratrol and piceid against peroxynitrite（ONOO-） were examined by the inhibition of 3-nitrotyrosine formation.Trolox was used as a positive control.Resveratrol and piceid exhibited high ONOO--scavenging activities in a concentration dependent manner.The antioxidant activities（the concentration of test compound required to yield a 50% inhibition of tyrosine nitration,IC 50） of resveratrol and piceid against ONOO-were（48.34±0.97） and（74.69±1.49） μmol/L,respectively.Compared with that of trolox[（105.40±1.16） μmol/L],their scavenging activities were 2.2-and 1.5-fold higher for resveratrol and piceid.Formation of nitroresveratrol as shown by UV-Vis spectroscopy and liquid chromatography-tandom mass spectrometry（LC-MS/MS） analysis indicates that resveratrol could directly scavenge ONOO-via nitration reaction.Our results demonstrate that foods and medicinal herbs with resveratrol and piceid as stronger ONOO-scavengers are valuable ingredients and have healthy application in preventing humans from peroxynitrite-mediated oxidative damage by scavenging peroxynitrite efficiently.展开更多
Electrocatalytic synthesis under mild conditions has become increasingly important as one of the practical alternatives for industrial applications,especially for the green ammonia(NH_(3))industry.A properly engineere...Electrocatalytic synthesis under mild conditions has become increasingly important as one of the practical alternatives for industrial applications,especially for the green ammonia(NH_(3))industry.A properly engineered electrocatalyst plays a vital role in the realization of superior catalytic performance.Among various types of promising nanomaterials,metal–organic frameworks(MOFs)are competitive candidates for developing efficient electrocatalytic NH_(3) synthesis from simple nitrogen-containing molecules or ions,such as N_(2) and NO_(3)^(−).In this review,recent advances in the development of electrocatalysts derived from MOFs for the electrosynthesis of NH_(3) are collected,categorized,and discussed,including their application in the N_(2) reduction reaction(NRR)and the NO_(3)^(−)reduction reaction(NO3RR).Firstly,the fundamental principles are illustrated,such as plausible mechanisms of NH_(3) generation from N_(2) and NO_(3)^(−),the apparatus of corresponding electrocatalysis,parameters for evaluation of reaction efficiency,and detection methods of yielding NH_(3).Then,the electrocatalysts for NRR processes are discussed in detail,including pristine MOFs,MOF-hybrids,MOF-derived N-doped porous carbons,single atomic catalysts from pyrolysis of MOFs,and other MOF-related materials.Subsequently,MOF-related NO3RR processes are also listed and discussed.Finally,the existing challenges and prospects for the rational design and fabrication of electrocatalysts from MOFs for electrochemical NH_(3) synthesis are presented,such as the evolution of investigation methods with artificial intelligence,innovation in synthetic methods of MOF-related catalysts,advancement of characterization techniques,and extended electrocatalytic reactions.展开更多
基金partially supported by the National Natural Science Foundation of China(No.22373092,No.22288201)CAS Project for Young Scientists in Basic Research(YSBR-051)supported by USTC Tang Scholarship。
文摘Utilizing nitrate(NO_(3)^(-))as the nitrogen source to produce ammonia can effectively remove NO_(3)^(-)pollutant while obtaining valuable ammonia,and the understanding of the mechanisms is essential for the design of new catalysts.In this work,by using density functional theory calculations,the electroreduction mechanisms of nitrate reduction reaction(NO_(3)RR)on transition metal single atom supported on 3N-coordinated N-doped graphene(TM/N_(3)-G)are systematically investigated.It is found that the protonation of ^(*)OH acts as the potential determing steps except for the traditionally considered ^(*)NO_(3)/^(*)NO/^(*)NO_(2) protonation step and the desorption of water may play an important role for NO_(3)RR on some TM/N_(3)-G.By considering the stability of single-atom catalyst(SAC),the preferential adsorption of NO_(3)^(-)larger than H and H_(2)O,the limiting potential of whole NO_(3)RR,the selectivity toward NH3,V(Mn,Os)/pyrrolic-N_(3)-G and Mn(Ru,Ir)/pyridinic-N_(3)-G are screened out as potential SACs for NO_(3)RR.This work provides an understanding of the NO_(3)RR mechanism and highlights several promising NO_(3)RR catalysts based on the TM/N_(3)-G system.
基金the Shandong Province Colleges and Universities Youth Innovation Technology Plan Innovation Team Project(2022KJ285)the National Natural Science Foundation of China(52202092)the Major Subject Project of the University of Jinan。
文摘Developing efficient electrocatalysts for the nitrate reduction reaction(NIRR)to ammonia is vital for environmental remediation and sustainable ammonia synthesis.Metal-oxide-based single-atom catalysts(SACs)offer atomic-scale efficiency,yet unclear anchoring strategies for single metal sites hinder their rational design.This study systematically explored the effects of surface-loading and latticedoping strategies on anchoring transition,rare-earth,and main-group metal atoms onto Co_(3)O_(4)via the synergy of machine learning and density functional theory calculations.Through a comprehensive assessment of stability,catalytic activity,and electronic structures,it is discovered that lattice-doping enhances SACs stability by firmly anchoring metal atoms on Co sites,while surface-loading significantly boosts catalytic activity for the NIRR.Calculations predicted that Al,Ir,Rh,and Mo sites anchored through the surface-loading strategy exhibited exceptional NIRR activity(the limiting potential for Al site can reaches-0.25 V versus the reversible hydrogen electrode),far surpassing many other configurations.To further decipher the underlying mechanisms,the machine learning algorithms,especially the treebased pipeline optimization tool model,revealed that SACs activity is highly correlated with the local environment of the active center,particularly its electronic and structural characteristics.This work establishes a new design paradigm for SACs,providing both theoretical guidelines for anchoring strategy selection and a predictive framework for efficient NIRR electrocatalysts.
基金supported by the National Natural Science Foundation of China(Grant Nos.:21825201,52401244 and 52201227)Henan Province Key Research and Development and Promotion Program(Scientific and Technological Breakthrough Project:232102240088 and 252102230078)+3 种基金the Key Research&Development and Promotion of Special Project(Scientific Problem Tackling)of Henan Province(252102230078)Doctoral Research Startup Fund Project of Henan Open University(BSJH-2025-04)Zhejiang Provincial Natural Science Foundation of China(LQ24B020005,LQ23B030001)China Postdoctoral Science Foundation(2024M762442).
文摘Electrocatalytic nitrate-to-ammonia conversion offers dual environmental and sustainable synthesis benefits,but achieving high efficiency with low-cost catalysts remains a major challenge.This review focuses on cobalt-based electrocatalysts,emphasizing their structural engineering for enhanced the performance of electrocatalytic nitrate reduction reaction(NO3RR)through dimensional control,compositional tuning,and coordination microenvironment modulation.Notably,by critically analyzing metallic cobalt,cobalt alloys,cobalt compounds,cobalt single atom and molecular catalyst configurations,we firstly establish correlations between atomic-scale structural features and catalytic performance in a coordination environment perspective for NO3RR,including the dynamic reconstruction during operation and its impact on active site.Synergizing experimental breakthroughs with computational modeling,we decode mechanisms underlying competitive hydrogen evolution suppression,intermediate adsorption-energy optimization,and durability enhancement in complex aqueous environments.The development of cobalt-based catalysts was summarized and prospected,and the emerging opportunities of machine learning in accelerating the research and development of high-performance catalysts and the configuration of series reactors for scalable nitrate-to-ammonia systems were also introduced.Bridging surface science and applications,it outlines a framework for designing multifunctional electrocatalysts to restore nitrogen cycle balance sustainably.
基金supported by the National Natural Science Foundation of China(Grant numbers 92061106 and 21971016).
文摘Direct electrochemical nitrate reduction reaction(NITRR)is a promising strategy to alleviate the unbalanced nitrogen cycle while achieving the electrosynthesis of ammonia.However,the restructuration of the high-activity Cu-based electrocatalysts in the NITRR process has hindered the identification of dynamical active sites and in-depth investigation of the catalytic mechanism.Herein,Cu species(single-atom,clusters,and nanoparticles)with tunable loading supported on N-doped TiO_(2)/C are successfully manufactured with MOFs@CuPc precursors via the pre-anchor and post-pyrolysis strategy.Restructuration behavior among Cu species is co-dependent on the Cu loading and reaction potential,as evidenced by the advanced operando X-ray absorption spectroscopy,and there exists an incompletely reversible transformation of the restructured structure to the initial state.Notably,restructured CuN_(4)&Cu_(4) deliver the high NH_(3) yield of 88.2 mmol h^(−1)g_(cata)^(−1) and FE(~94.3%)at−0.75 V,resulting from the optimal adsorption of NO_(3)^(−) as well as the rapid conversion of^(*)NH_(2)OH to^(*)NH_(2) intermediates originated from the modulation of charge distribution and d-band center for Cu site.This work not only uncovers CuN_(4)&Cu_(4) have the promising NITRR but also identifies the dynamic Cu species active sites that play a critical role in the efficient electrocatalytic reduction in nitrate to ammonia.
基金National Natural Science Foundation of China(Nos.52172291 and 52122312)“Dawn”Program of Shanghai Education Commission,China(No.22SG31)。
文摘The accumulation of excessive nitrate in the atmosphere not only jeopardizes human health but also disrupts the balance of the nitrogen cycle in the ecosystem.Among various nitrate removal technologies,electrocatalytic nitrate reduction reaction(eNO_(3)RR)has been widely studied for its advantages of being eco-friendly,easy to operate,and controllable under environmental conditions with renewable energy as the driving force.Transition metal-based catalysts(TMCs)have been widely used in electrocatalysis due to their abundant reserves,low costs,easy-to-regulate electronic structure and considerable electrochemical activity.In addition,TMCs have been extensively studied in terms of the kinetics of the nitrate reduction reaction,the moderate adsorption energy of nitrogen-containing species and the active hydrogen supply capacity.Based on this,this review firstly discusses the mechanism as well as analyzes the two main reduction products(N_(2)and NH_(3))of eNO_(3)RR,and reveals the basic guidelines for the design of efficient nitrate catalysts from the perspective of the reaction mechanism.Secondly,this review mainly focuses on the recent advances in the direction of eNO_(3RR)with four types of TMCs,Fe,Co,Ni and Cu,and unveils the interfacial modulation strategies of Fe,Co,Ni and Cu catalysts for the activity,reaction pathway and stability.Finally,reasonable suggestions and opportunities are proposed for the challenges and future development of eNO_(3)RR.This review provides far-reaching implications for exploring cost-effective TMCs to replace high-cost noble metal catalysts(NMCs)for eNO_(3)RR.
基金financially supported by the National Nature Science Foundation of China (Nos. 62001097, 22208048)the Provincial Natural Science Foundation Joint Guidance Project (No. LH2020F001)+2 种基金the Young Elite Scientists Sponsorship Program by CAST (No. YESS20210262)the China Postdoctoral Science Foundation-Funded Project (No. 2021M690571)the Heilongjiang Postdoctoral Fund (No. LBH-Z21096)
文摘Mass transfer can tune the surface concentration of reactants and products and subsequently infl uence the catalytic perfor-mance.The morphology of nanomaterials plays an important role in the mass transfer of reaction microdomains,but related studies are lacking.Herein,a facile electrospinning technique utilizing cellulose was employed to fabricate a series of carbon nanofi bers with diff erent diameters,which exhibited excellent electrochemical nitrate reduction reaction and oxygen evolu-tion reaction activities.Furthermore,the microstructure of electrocatalysts could infl uence the gas-liquid-solid interfacial mass transfer,resulting in diff erent electrochemical performances.
基金supported by the National Key Research and Development Program of China(2023YFE0120900)the National Natural Science Foundation of China(52377160)+2 种基金the National Natural Science Foundation of China National Young Talents Project(GYKP010)Shaanxi Provincial Natural Science Program(2023-JCYB-425)Xi’an Jiaotong University Young Top Talents Program。
文摘Ammonia is the cornerstone of modern agriculture,providing a critical nitrogen source for global food production and serving as a key raw material for numerous industrial chemicals.Electrocatalytic nitrate reduction,as an environmentally friendly method for synthesizing ammonia,not only mitigates the reliance on current ammonia synthesis processes fed by traditional fossil fuels but also effectively reduces nitrate pollution resulting from agricultural and industrial activities.This review explores the fundamental principles of electrocata lytic nitrate reduction,focusing on the key steps of electron transfer and ammonia formation.Additionally,it summarizes the critical factors influencing the performance and selectivity of the reaction,including the properties of the electrolyte,operating voltage,electrode materials,and design of the electrolytic cell.Further discussion of recent advances in electrocatalysts,including pure metal catalysts,metal oxide catalysts,non-metallic catalysts,and composite catalysts,highlights their significant roles in enhancing both the efficiency and selectivity of electrocata lytic nitrate to ammonia(NRA)reactions.Critical challenges for the industrial NRA trials and further outlooks are outlined to propel this strategy toward real-world applications.Overall,the review provides an in-depth overview and comprehensive understanding of electrocata lytic NRA technology,thereby promoting further advancements and innovations in this domain.
基金financially supported by the National Natural Science Foundation of China(Nos.22209040 and 22202063)。
文摘Zinc-nitrate battery could produce electrical power,remove pollutant nitrate and obtain value-added ammonia,where the cathodic reaction of converting nitrate to ammonia is sluggish and complex due to the involvement of multi-electron transfer.Thus,highly efficient catalysts for nitrate reduction reaction(NO_(3)RR)are greatly needed.In this work,we report a high entropy hydroxide(HE-OH)as an excellent NO3RR catalyst,which could achieve high NH_(3)Faradaic efficiencies(e.g.,nearly 100%at-0.3 V versus reversible hydrogen electrode)and high yield rates(e.g.,30.4 mg h^(-1)cm^(-2)at-0.4 V).Moreover,HE-OH could also deliver a current density of 10 mA/cm^(2) at an overpotential of 260 mV for oxygen evolution reaction.The assembled zinc-nitrate battery using HE-OH as the cathode demonstrates a high power density(e.g.,3.62 mW/cm^(2)),rechargeability and stability.
基金support from the National Key R&D Program of China(2020YFA0710000)the National Natural Science Foundation of China(22278307,22008170,22222808,21978200)the Haihe Laboratory of Sustainable Chemical Transformations。
文摘The electrochemical nitrate reduction reaction(NO_(3)^(-)RR)represents a promising and environmentally friendly approach for both the removal of nitrate(NO_(3)^(-))pollutants and the production of high-value ammonia(NH_(3)).However,this process faces significant challenges in achieving industrial application due to mismatched reaction kinetics involved in the conversion of NO_(3)^(-)to NO_(2)^(-),the formation of active hydrogen(H^(*))via water dissociation,and the stepwise hydrogenation processes.In this study,we developed a trimetallic CuCoRu catalyst with multiple active sites to enhance the selective NH_(3)synthesis at industrial-scale current density,where Cu primarily catalyzes the reduction of NO_(3)^(-)to NO_(2)^(-),Co facilitates the deep hydrogenation of NO_(2)^(-)to NH_(3),and Ru promotes water dissociation to generate H^(*),effectively bridging the aforementioned processes.The optimized CuCoRu catalyst achieves near-100%NH_(3)Faradaic efficiency with an NH_(3)yield rate of 14.6 mmol h^(-1)cm^(-2)at a current density of 2.5 A cm^(-2).The practical application in simulated wastewater with different NO_(3)^(-)concentrations and in the membrane electrode assembly demonstrates great potential for industrial application.
基金supported by the Water Conservancy Science and Technology Project of Jiangsu Province,China(No.2024005,2025012)。
文摘Electrochemical nitrate(NO_(3)^(-))reduction reaction(eNO_(3)RR)presents a promising and sustainable strategy for converting environmentally hazardous NO_(3)^(-)into value-added ammonia(NH3),thereby addressing both pollution mitigation and nitrogen resource recovery.However,its practical implementation remains hindered by the limited availability of electrocatalysts that simultaneously offer high activity,selectivity,and stability.In this study,we systematically investigate the catalytic potential of 300 Cu-based heteronuclear trimetallic dual-atom alloys(DAAs),featuring heterometallic dual-atom active sites embedded on a catalytically suboptimal Cu(111)surface.By combining high-throughput firstprinciples calculations with a hierarchical four-step screening strategy,we efficiently identify promising DAA catalysts for eNO_(3)RR.Among them,CrRh and MnRh catalysts stand out,exhibiting ultralow limiting potentials of-0.16 and-0.25 V,respectively,along with excellent selectivity and stability.Constantpotential simulations further reveal that both catalysts maintain high activity and selectivity across varying pH conditions and applied potentials.Geometric and electronic structure analyses indicate that the incorporation of dual-atom sites induces local lattice distortion and charge polarization,effectively tuning the electronic structure of the active centers.Notably,strong d-d orbital interactions between the embedded metal dimers give rise to new molecule-like electronic states near the Fermi level.These states facilitate effective activation of NO_(3)^(-)and NO via an electron“acceptance-donation”mechanism,driven by p-d orbital interactions between adsorbates and metal dimers.This work not only strategically designs efficient heteronuclear Cu-based DAA catalysts but also provides valuable insights into the electronic synergistic effects of dual-atom sites in modulating eNO_(3)RR performance.It establishes a promising platform for demonstrating the feasibility of constructing dual-atom active centers on pure metal surfaces for eNO_(3)RR,while broadening the potential applications of DAAs in electrocatalysis and related fields.
基金financial support from the National Natural Science Foundation of China(NSFC 22172082)the Fundamental Research Funds for the Central Universities。
文摘Mild electrocatalytic nitrate reduction reaction(NO_(3)RR),driven by renewable electricity,is regarded as a desirable strategy for green ammonia synthesis and simultaneous removal of nitrogen-containing environmental pollutants.In view of different supply voltages from renewable energy sources,developing costeffective and efficient electrocatalysts with a wide operating potential window is very meaningful for practical application.However,currently reported catalysts usually need to introduce noble metals to synergistically achieve wide-potential selective ammonia synthesis from nitrate.In this work,we present for the first time a dual-transition-metal electrocatalyst(Fe_(3)C-CuO_(x)@NC,x=0,1)with wide-potential-adaptability for highly selective nitrate reduction to ammonia.Such Fe_(3)C-CuO_(x)@NC with spatially separated CuO_(x)and noblemetal-like Fe_(3)C nanoparticles encapsulated with nitrogen-doped graphitized carbon,exhibits outstanding performance in NO_(3)RR with desirable NH_(3)Faraday efficiency of more than 90%over a wide potential ranging from-0.2 V vs.RHE to-0.6 V vs.RHE,comparable to the reported noble metal catalysts.Different from common tandem catalysis,the wide-potential high ammonia selectivity of Fe_(3)C-CuO_(x)@NC is domina ntly ascribed to the complementary enhancement between CuO_(x)and Fe_(3)C,fully supported by results of experiments and density function theory calculations.CuO_(x)exhibit highly intrinsic nitrate reduction to nitrite to compensate for the slow potential determination step(^(*)NO_(3)→^(*)NO_(3)H)of Fe_(3)C,while Fe_(3)C,besides behaving like noble metals to supply adequate active hydrogens,has both good adsorption and reduction abilities for nitrite species to ammonia.Moreover,Fe_(3)C partially stabilizes active Cu^(0)/Cu^(+)sites,and the unique carbon-layer enca psulation structure effectively prevents the agglomeration and corrosion of metal nanoparticles during the electrocatalysis,thus maintaining good cyclic stability.The Zn-NO_(3)^(-)battery assembled with Fe_(3)C-CuO_(x)@NC can reach a high power density of 5.2 mW cm^(-2)at a potential of 1.0 V vs.Zn,with an NH_(3)Faraday efficiency of 92.4%at a current of 8.0 mA,proving its potential practical application.This advance provides unique insights into complementary catalysis mechanisms on multiple metal sites in NO_(3)RR,and offers a reference for the design of other transition metal electrocatalysts matching with renewable electricity.
基金supported by the National Natural Science Foundation of China-Yunnan Joint Fund(No.U2002213)the Science and Technology Talent and Platform Program of Yunnan Provincial Science and Technology Department(No.202305AM070001)+1 种基金Open Foundation of Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials(No.2022GXYSOF10)Double First University Plan(No.C176220100042)
文摘Electrochemical reduction reactions,including the oxygen reduction reaction(ORR),hydrogen evolution reaction(HER),carbon dioxide reduction reaction(CRR),and nitrate reduction reaction(NRR),hold promise for energy conversion and storage.However,electrocatalysts exhibit slow kinetics and inactivation effects,resulting in inadequate energy efficiency and poor stability.To address these challenges,the groupⅧelement-based single-atom electrocatalysts(GVSAEs)were endowed with tunable electronic structures and porous carbon substrates to reduce intermediate adsorption and desorption energy barriers,which can accelerate electrochemical kinetics.This mini review summarises the recent achievements in GVSAEs with electronic structure and porous substrate engineering discussions.Furthermore,these GVSAEs are divided into non-noble iron series element(Fe,Co,and Ni)single-atom electrocatalysts and noble platinum series elements(Ru,Rh,Pd,Os,Ir,and Pt)based single-atom electrocatalysts for the ORR,HER,CRR,and NRR,where the porous substrate structure,electronic structure,and catalytic activity are discussed.Finally,conclusions and perspectives relating to future challenges and potential opportunities are provided for electrocatalysis with better performance.
基金the financial support from the National Natural Science Foundation of China(22479074 and 22475096)the Natural Science Foundation of Sichuan Province(2023NSFSC1074 and 2025NSFTD0005)+9 种基金the Talent Introduction Plan of Xihua University(Z222051)the Equipment Pre-Research and MOE Joint Fund General Project(8091B02052407)the National Science Foundation of Jiangsu Province(BK20240400 and BK20241236)the Jiangsu Province Science and Technology Major Project(BG2024013)the Jiangsu Province Scientiflc and Technological Achievenments Transformation Special Fund(BA2023037)the Jiangsu Province Academic Degree and Postgraduate Education Reform Project(JGKT24_C001)the Suzhou City Key Core Technology Open Competition Project(SYG2024122)the Open Research Fund of Suzhou Laboratory(SZLAB-1308-2024TS005)the Suzhou City Gusu Leading Talent Program of Scientific and Technological Innovation and Entrepreneurship(ZXL2021273)the Chenzhou National Sustainable Development Agenda Innovation Demonstration Zone Provincial Special Project(2023sfq11)。
文摘Atomically precise copper-based nanoclusters stand out as one of the highly promising catalysts in the realm of electrochemical nitrate reduction reaction(NITRR)aimed at ammonia(NH_(3))synthesis.However,the controllable synthesis of stable Cu-based nanoclusters featuring fully inorganic anionic ligands for electrochemical NITRR remains a challenge.Herein,we present a simple and gentle chelated co-precipitation method for the uniform growth of ultrafine amorphous Cu(OH)Cl(a-Cu(OH)Cl)nanoclusters,featuring a diameter of approximately 9 nm,onto carbon nanotubes(a-Cu(OH)Cl/CNTs),aimed at enhancing electrocatalytic NITRR performance.Intriguingly,trisodium citrate dihydrate(TCD)could effectively change the crystalline form of Cu-based nanoclusters to obtain a-Cu(OH)Cl nanoclusters instead of high-crystallinity Cu_(2)(OH)_(3)Cl(c-Cu_(2)(OH)_(3)Cl)nanoclusters.In comparison to c-Cu_(2)(OH)_(3)Cl nanoclusters,a-Cu(OH)Cl nanoclusters,featuring a smaller particle size and containing more lowcoordination Cu atoms,provide more efficient catalytic sites,thereby enhancing the reaction rate and energy efficiency for NH_(3)production.The proposed chelated co-precipitation method provides a promising crystalline modulation engineering strategy to boost the electrocatalytic performances of metal nanoclusters.
基金supported in part by National Natural Science Foundation of China(No.51925102)National Key R&D Program of China(No.2022YFA1504101)。
文摘In this work,an effective catalyst of Cu/MnOOH has been successfully constructed for electrochemical nitrate reduction reaction(e NO_(3)RR)for synthesis of ammonia(NH_(3))under ambient conditions.The substrate of MnOOH plays an important role on the size and electronic structure of Cu nanoparticles,where Cu has the ultrafine size of 2.2 nm and positive shift of its valence states,which in turn causes the increased number of Cu active sites and enhanced intrinsic activity of every active site.As a result,this catalyst realizes an excellent catalytic performance on eNO_(3)RR with the maximal NH_(3)Faraday efficiency(FE)(96.8%)and the highest yield rate(55.51 mg h^(-1)cm^(-2))at a large NH_(3)partial current density of700 m A/cm^(2),which could help to promote the industrialization of NH_(3)production under ambient conditions.
文摘In this paper we report the preparation of nano-dendritic Cu_(2)O/Cu heterojunctions doped with varying concentrations of cobalt through a convenient,energy-consumption-free,and environmentally friendly chemical replacement method.The analysis results reveal that the incorporation of cobalt in its atomic form enhances the adsorption of nitrate species onto the catalyst surface,whereas doping with metallic cobalt promotes the production of active hydrogen(*H).By adjusting the doping concentration of cobalt,we effectively control its doping form(atomic and metallic states)on the surface of dendritic copper,thereby enabling controllable modulation of the active hydrogen concentration on the catalyst surface.By ensuring sufficient consumption of*H during the NITRR process while avoiding excessively high concentrations that could trigger detrimental hydrogen evolution reaction side reactions,this approach remarkably enhances the selectivity of ammonia synthesis in NITRR.This study offers an effective approach to regulate the*H concentration on the surface of the catalyst through adjusting the metal doping form,thereby improving the performance of ammonia synthesis from NITRR.
基金upported by the National Natural Science Foundation of China(Nos.U22A20253,52272293,and 52401275)the Fellowship of China Postdoctoral Science Foundation(No.2021M701116).
文摘Modulating the adsorption energy of intermediate species via alloying presents a promising approach to enhance the electrocatalytic nitrate reduction to ammonia(NRA).Nonetheless,the synthesis of alloy catalysts that are uniformly distributed and structurally stable poses significant challenges.Herein,the CuNi alloy was successfully anchored on oxygen vacancy-rich N-Ti_(3)C_(2)T_(x) through metal-support interactions(MSI).The three-dimensional(3D)wrinkled morphology of N-Ti_(3)C_(2)T_(x) MXene was achieved by employing melamine-formaldehyde spheres(MFs)as self-sacrificial templates,which effectively prevented the restacking of the Ti_(3)C_(2)T_(x) layers,thereby increasing specific surface area and promoting the formation of surface oxygen vacancies.Ti–O–M structure plays a crucial role in inhibiting both particle migration and metal atom diffusion.X-ray photoelectron spectroscopy(XPS)analysis confirms moderate metal-support interactions between the CuNi alloy and N-Ti_(3)C_(2)T_(x),leading to the establishment of stable Ti–O–M bonds and charge redistribution within the Ti-O-M framework.The Cu_(5)Ni_(5)/N-Ti_(3)C_(2)T_(x) sample achieves an impressive Faradaic efficiency(FE)of 97.50%at−0.27 V vs.RHE,alongside the highest NH3 yield rate of 527.44µmol h−1 cm−2.In-situ electrochemical Raman spectroscopy and theoretical calculations reveal that the high intrinsic catalytic activity of NRA can be attributed to the synergistic effects between the CuNi alloy and the interfacial metal-oxygen interactions.This work provides significant perspectives on the design of interfacial metal interactions and the development of durable electrocatalysts.
基金supported by the Natural Scientific Foundation of China(Nos.22127803,22174110,22203050)Natural Scientific Foundation of Shandong(No.ZR2022QB002)China Postdoctoral Science Foundation(No.2020T130331)。
文摘A novel Cu-t-ZrO_(2)catalyst with enhanced electronic metal-support interaction(EMSI)is designed for efficient electrocatalytic conversion of nitrate(NO_(3^(-)))to ammonia(NH_(3)),achieving a remarkable Faradaic efficiency and yield rate of 97.54%and 33.64 mg h^(-1)mg_(cat)^(-1),respectively.Electrons are more likely to be transferred from Cu to t-ZrO_(2)at the electron-rich interface due to the lower work function,which promotes the formation of highly active Cu species and facilitates NO_(3^(-))adsorption,ensuring selective conversion into NH_(3).
基金financially supported by the National Key Research and Development Program of China(No.2021YFB4000604)National Natural Science Foundation of China(No.52271220)+2 种基金The Program of the Ministry of Education of China for Introducing Talents of Discipline to Universities(No.B12015)the Fundamental Research Funds for the Central UniversitiesHaihe Laboratory of Sustainable Chemical Transformations,Guangxi Collaborative Innovation Centre of Structure and Property for New Energy and Materials,Science Research and Technology Development Project of Guilin(No.20210102-4)
文摘Electrochemical nitrate(NO_(3)^(-))reduction reaction(eNO_(3)RR)to ammonia(NH3)provides a promising route for both water conservation and green ammonia synthesis.Although various catalysts were designed for the eNO_(3)RR and great achievements have been achieved,it is still a challenge to realize selective eNO_(3)RR to NH3at low concentration for the competing hydrogen evolution reaction(HER)and poor mass transfer of NO_(3)^(-).Herein,we designed a tandem catalyst of Pd nanoparticle loaded Cu_(2)O hierarchical nanofiber(Pd-Cu_(2)O)to improve eNO_(3)RR performance at low nitrate concentration.The Pd-Cu_(2)O shows a faraday efficiency(FE)of 95.80%and an ammonia selectivity of 97.34%at a comparatively low applied potential of-0.15 V versus RHE with low concentration.Besides,it exhibits excellent nitrate removal effects,the residual concentration of nitrate-N was only 7.22 ppm at-0.15 V.Electrochemical characterizations indicate that the abundant secondary heterojunction structures and the tandem effects of Pd-Cu_(2)O synergistic ally accelerate the transfer and conversion of NO_(3)^(-)and improve the dynamic of eNO_(3)RR at low concentration.Furthermore,the operando electrochemical impedance spectroscopy(EIS)and density functional theory(DFT)calculations suggested the tandem effects of Pd-Cu_(2)O improved the adsorption of NO_(3)^(-)and*H and thus promoted the dynamics of eNO_(3)RR at low concentration.The findings highlight the tandem effects of Pd-Cu_(2)O and provide an effective strategy for designing electrocatalysts that can be applied to low concentration and low applied potential conditions.
基金Supported by the National Basic Research Program of China(Nos.2012CB721105,2011CBA00802,2007CB714301)the National Natural Science Foundation of China(No.30873400)the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20090032110015)
文摘In vitro antioxidant activities of resveratrol and piceid against peroxynitrite（ONOO-） were examined by the inhibition of 3-nitrotyrosine formation.Trolox was used as a positive control.Resveratrol and piceid exhibited high ONOO--scavenging activities in a concentration dependent manner.The antioxidant activities（the concentration of test compound required to yield a 50% inhibition of tyrosine nitration,IC 50） of resveratrol and piceid against ONOO-were（48.34±0.97） and（74.69±1.49） μmol/L,respectively.Compared with that of trolox[（105.40±1.16） μmol/L],their scavenging activities were 2.2-and 1.5-fold higher for resveratrol and piceid.Formation of nitroresveratrol as shown by UV-Vis spectroscopy and liquid chromatography-tandom mass spectrometry（LC-MS/MS） analysis indicates that resveratrol could directly scavenge ONOO-via nitration reaction.Our results demonstrate that foods and medicinal herbs with resveratrol and piceid as stronger ONOO-scavengers are valuable ingredients and have healthy application in preventing humans from peroxynitrite-mediated oxidative damage by scavenging peroxynitrite efficiently.
基金support from the Natural Science Foundation of Liaoning Province(general program)(2020-MS-137)T.J.White would like to thank the MOE2019-T2-2-032 grant and Monetary Academic Resources for Research Grant 001561-00001 in Nanyang Technological University,Singapore+9 种基金T.Ma would like to thank the National Natural Science Foundation of China(Nos.52071171,52202248)Liaoning BaiQianWan Talents Program(LNBQW2018B0048)Shenyang Science and Technology Project(21-108-9-04)Australian Research Council(ARC)through Future Fellowship(FT210100298,FT210100806)Discovery Project(DP220100603)Linkage Project(LP210100467,LP210200504,LP210200345,LP220100088)Industrial Transformation Training Centre(IC180100005)schemesthe Australian Government through the Cooperative Research Centres Projects(CRCPXIII000077)F.Wei would like to thank the A^(*)STAR career development fund C210112054Singapore structural metal alloy program grant No.A18b1B0061.A.K.Cheetham would like to thank the Ras al Khaimah Centre for Advanced Materials.
文摘Electrocatalytic synthesis under mild conditions has become increasingly important as one of the practical alternatives for industrial applications,especially for the green ammonia(NH_(3))industry.A properly engineered electrocatalyst plays a vital role in the realization of superior catalytic performance.Among various types of promising nanomaterials,metal–organic frameworks(MOFs)are competitive candidates for developing efficient electrocatalytic NH_(3) synthesis from simple nitrogen-containing molecules or ions,such as N_(2) and NO_(3)^(−).In this review,recent advances in the development of electrocatalysts derived from MOFs for the electrosynthesis of NH_(3) are collected,categorized,and discussed,including their application in the N_(2) reduction reaction(NRR)and the NO_(3)^(−)reduction reaction(NO3RR).Firstly,the fundamental principles are illustrated,such as plausible mechanisms of NH_(3) generation from N_(2) and NO_(3)^(−),the apparatus of corresponding electrocatalysis,parameters for evaluation of reaction efficiency,and detection methods of yielding NH_(3).Then,the electrocatalysts for NRR processes are discussed in detail,including pristine MOFs,MOF-hybrids,MOF-derived N-doped porous carbons,single atomic catalysts from pyrolysis of MOFs,and other MOF-related materials.Subsequently,MOF-related NO3RR processes are also listed and discussed.Finally,the existing challenges and prospects for the rational design and fabrication of electrocatalysts from MOFs for electrochemical NH_(3) synthesis are presented,such as the evolution of investigation methods with artificial intelligence,innovation in synthetic methods of MOF-related catalysts,advancement of characterization techniques,and extended electrocatalytic reactions.
