Electrocatalytic nitrate reduction reaction (NO_(3)-RR) to ammonia under ambient conditions is expected to be a green process for ammonia synthesis and alleviate water pollution issues.We report a CuO nanoparticles in...Electrocatalytic nitrate reduction reaction (NO_(3)-RR) to ammonia under ambient conditions is expected to be a green process for ammonia synthesis and alleviate water pollution issues.We report a CuO nanoparticles incorporated on nitrogen-doped porous carbon (CuO@NC) catalyst for NO_(3)-RR.Part of Cu(Ⅱ) is reduced to Cu(Ⅰ) during the NO_(3)-RR process to construct Cu(Ⅰ)-Cu(Ⅱ) pairs,confirmed by in situ X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy.Density functional theory (DFT) calculations indicated that the formation of Cu(Ⅰ) could provide a reaction path with smaller energy barrier for NO_(3)-RR,while Cu(Ⅱ) effectively suppressed the competition of hydrogen evolution reaction (HER).As a result,CuO@NC catalyst achieved a Faradaic efficiency of 84.2% at -0.49 V versus reversible hydrogen electrode (RHE),and a NH_(3)yield rate of 17.2 mg h^(-1)mg^(-1)cat.at -0.79 V vs.RHE,higher than the HaberBosch process (<3.4 g h^(-1)g^(-1)cat.).This work may open a new avenue for effective NO_(3)-RR by modulating oxidation states.展开更多
Red mud(RM)is a solid waste generated in the aluminum industry after the extraction of alumina oxide;its multiple elements and higher pH value likely pose a severe threat to the environment after treatment.However,RM&...Red mud(RM)is a solid waste generated in the aluminum industry after the extraction of alumina oxide;its multiple elements and higher pH value likely pose a severe threat to the environment after treatment.However,RM's higher concentrations of metal components,particularly Fe_(2)O_(3)and rare earth elements(REEs),render RM promising for catalytic application.Hence,this work showed an efficient high-speed RM to catalyze electrocatalytic nitrate-to-ammonia reduction reaction(NARR).RM calcined at 500℃(RM-500)exhibited excellent catalytic performance.Faradaic efficiency of ammonia(FENH_(3))in an electrolyte solution containing 1 mol·L^(-1)NO_(3)-achieved a maximum value of 92.3%at-0.8 V(vs.RHE).Additionally,24-h cycle testing and post-reaction PXRD and SEM indicated that the RM-500 electrocatalyst is stable during NARR.The RM-500 demonstrated a high FE of NH_(3)-to-NO_(3)-of 89.7%at 1.85 V(vs.RHE),showing great potential in the ammonia fuel cells technology and achieving the nitrogen cycle.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
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
The excess emission of nitrate from human activities disturbs the global nitrogen cycle and thus needs to be remediated.In this work,we prepared a La-doped Co_(3)O_(4)nanoneedle arrays catalyst for highly efficient el...The excess emission of nitrate from human activities disturbs the global nitrogen cycle and thus needs to be remediated.In this work,we prepared a La-doped Co_(3)O_(4)nanoneedle arrays catalyst for highly efficient electrocatalytic reduction of NO_(3)^(-) to NH_(3)at low concentration.The La-doped Co_(3)O_(4)nanoneedle arrays exhibit remarkable activity with the highest Faradaic efficiency of 95.5%and an ammonia yield rate of 4.08 mg/(h·cm^(2))at-0.3 V versus RHE in 0.02 mol/L NO_(3)^(-).Experiments and theoretical calculations show that the La doping not only facilitates the surface reconstruction to form active La-Co(OH)_(2),but also inhibits the hydrogen evolution reaction over Co sites,thus promoting the NH_(3)production.This work provides new insights into the promoting effect of the rare earth elements in transition metalbased electrocatalyst for nitrate reduction.展开更多
The efficient electrocatalytic nitrate(NO_(3)^(−))reduction to ammonia(NRA)offers a sustainable alternative for both environmental remediation and ammonia synthesis.Developing advanced electrocatalysts with rationally...The efficient electrocatalytic nitrate(NO_(3)^(−))reduction to ammonia(NRA)offers a sustainable alternative for both environmental remediation and ammonia synthesis.Developing advanced electrocatalysts with rationally designed spatial arrangement of active sites and optimizing the synergetic effect among components are crucial for high efficiency and selectivity.Herein,we present Fe/N active sites decorated on porous carbon nanofibers(CNFs)with encapsulated FeCo nanoparticles(FeCo@CNFs-Fe/N)as electrocatalysts for NRA.The FeCo@CNFs-Fe/N catalyst demonstrates exceptional performance,achieving a high ammonia yield of 498.18μmol/(h·g_(cat)).Meanwhile,the enhanced reduction activity,especially the reduction in overpotential by 0.565 V,is 3–10 times higher than that of FeCo-encapsulated and Fe/N-modified CNFs-based catalysts.The enhanced catalytic activity is attributed to the efficient structure design and optimized spatial distribution of active sites,which enhance the electron transfer rate and decrease the reaction energy barrier.Mechanistic studies reveal that the synergetic effect between encapsulated nanoparticles and surface-modified Fe/N sites plays a crucial role in promoting efficient nitrate adsorption and selective ammonia production.These findings highlight the potential of strategically engineered CNF-based composites for nitrate reduction and other advanced electrocatalytic applications.展开更多
Catalytic reduction of nitrate over bimetallic catalysts has emerged as a technology for sustainable treatment of nitrate-containing groundwater.However,the structure of bimetallic has been much less investigated for ...Catalytic reduction of nitrate over bimetallic catalysts has emerged as a technology for sustainable treatment of nitrate-containing groundwater.However,the structure of bimetallic has been much less investigated for catalyst optimization.Herein,two main types of Pd-Cu bimetallic nanocrystal structures,heterostructure and intermetallic,were prepared and characterized using high-resolution transmission electron microscopy(HRTEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The results show that two individual Pd and Cu nanocrystals with a mixed interface exist in the heterostructure nanocrystals,while Pd and Cu atoms are uniformly distributed across the intermetallic Pd-Cu nanocrystals.The catalytic nitrate reduction experiments were carried out in a semibatch reactor under constant hydrogen flow.The nitrate conversion rate of the heterostructure Pd-Cu nanocrystals supported onα-Al_(2)O_(3),γ-Al_(2)O_(3),SBA-15,and XC-72R exhibited 3.82-,6.76-,4.28-,2.44-fold enhancements relative to the intermetallic nanocrystals,and the nitrogen and nitrite were the main products for the heterostructure and intermetallic Pd-Cu nanocrystals,respectively.This indicates that the catalytic nitrate reduction over Pd-Cu catalyst is sensitive to the bimetallic structures of the catalysts,and heterostructure bimetallic nanocrystals exhibit better catalytic performances on both the activity and selectivity,which may provide new insights into the design and optimization of catalysts to improve catalytic activity and selectivity for nitrate reduction in water.展开更多
Electrochemical nitrate reduction(NO_(3)RR)offers a promising avenue for treating nitrate-contaminated water and recovering ammonia(NH_(3)),yet the complexities of direct electron transfer(DET)and hydrogen atom transf...Electrochemical nitrate reduction(NO_(3)RR)offers a promising avenue for treating nitrate-contaminated water and recovering ammonia(NH_(3)),yet the complexities of direct electron transfer(DET)and hydrogen atom transfer(HAT)mechanisms crucial for efficiency remain elusive.This study bridges the gap with a combined experimental and theoretical approach,elucidating the impact of catalyst structure on NO3RR pathways.We discover that catalysts favoring strong NO_(3^(-))adsorption and efficient water dissociation were more inclined towards DET,enhancing denitrification.The Fe@Fe_(3)O_(4)/FF cathode,leveraging the synergistic interplay between metallic Fe and Fe_(3)O_(4),excelled in NO3RR via DET,achieving an NH3yield of 0.28 mmol h-1cm-2and a Faradaic efficiency of 95.7%for NH3at-1.6 V(vs.SCE),with minimal nitrite accumulation at 100 mmol/L nitrate.Conversely,the Fe/FF and Fe_(3)O_(4)/CC cathodes showed reduced NH3production and increased nitrite levels,attributed to the lack of Fe_(3)O_(4)and metallic Fe,respectively,resulting in a dominant HAT mechanism.Moreover,Fe@Fe_(3)O_(4)/FF facilitated complete denitrification in real wastewater treatment by harnessing Cl^(-)for electrochemically mediated breakpoint chlorination.This research not only deepens our understanding of NO3RR mechanisms but also paves the way for designing superior nitrate reduction catalysts.展开更多
The electrochemical conversion of nitrate,a widespread water pollutant,into valuable ammonia represents a green and decentralized approach to ammonia synthesis.However,the sluggish multielectronproton coupling path an...The electrochemical conversion of nitrate,a widespread water pollutant,into valuable ammonia represents a green and decentralized approach to ammonia synthesis.However,the sluggish multielectronproton coupling path and the low reactive species(nitrate and proton)concentration at the catalyst interface inhibit the efficiency of ammonia production from nitrate reduction reaction(NitRR).Herein,we introduce a novel iron-based tandem catalyst encapsulated by reduced graphene oxide(denoted as Fe-rGO),with a superior ammonia production rate of 47.815 mg h^(-1)mg_(ca)^(t-1)and a high Faraday efficiency(FE)of 96.51%at an applied potential of-0.5 V.It also delivers a robust stability with FE above90%under a current density of 250 mA cm^(-2)for 50 h.In situ X-ray absorption spectroscopy reveals that the FeO_(x)is dynamically translated to Fe~0 site concurrently with the enhancement of the NH_(3)production rate,suggesting the Fe^(0) site as hydrogenation active center.The asymmetric distribution of surface charges of rGO not only enriches nitrate ions at the catalytic interface and promotes the hydrogenation process in NitRR,but also protects the iron species and ensures their stability during electrolysis.The Zn-NO_(3)^(-)battery demonstrates an impressive FE of 88.6%,highlighting its exceptional potential for practical applications.展开更多
Electrocatalytic nitrate reduction reaction(NitRR)utilizing water as a hydrogen source under ambient conditions represents a highly promising avenue for sustainable ammonia synthesis and environmental remediation.Howe...Electrocatalytic nitrate reduction reaction(NitRR)utilizing water as a hydrogen source under ambient conditions represents a highly promising avenue for sustainable ammonia synthesis and environmental remediation.However,achieving high efficiency and selectivity in NitRR is fundamentally challenged by the complex lifecycle management of active hydrogen derived from water splitting.This review provides a timely and comprehensive analysis centered on the pivotal role and meticulous regulation of active hydrogen throughout the NitRR process.We first elucidate the distinct functions and characteristics of various hydrogen species,followed by a survey of advanced characterization techniques crucial for monitoring the dynamics of active hydrogen.Critically,three core strategies were systematically dissected to modulate the active hydrogen lifecycle:accelerating water activation and dissociation,enhancing the directional transport of hydrogen species,and precisely tuning active hydrogen coupling pathways while suppressing parasitic hydrogen evolution.By consolidating current understanding from both catalyst design and reaction mechanism perspectives,this review offers a hydrogen-centric roadmap and highlights emerging opportunities for rationally engineering advanced NitRR systems.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
Nitrate pollution poses a significant environmental challenge,and photocatalytic nitrate reduction has garnered considerable attention due to its efficiency and environmental advantages.Among these,the development of ...Nitrate pollution poses a significant environmental challenge,and photocatalytic nitrate reduction has garnered considerable attention due to its efficiency and environmental advantages.Among these,the development of Schottky junctions shows considerable potential for practical applications.However,the impact of metal nanoparticle size within Schottky junctions on photocatalytic nitrate reduction remains largely unexplored.In this study,we propose a novel method to modulate metal nanoparticle size within Schottky junctions by controlling light intensity during the photodeposition process.Smaller Au nanoparticles were found to enhance electron accumulation at active sites by promoting charge transfer from COF to Au,thereby improving internal electron transport.Additionally,the Schottky barrier effectively suppressed reverse electron transfer while enhancing NO_(3)^(–)adsorption and activation.The Au_(2-)COF exhibited remarkable nitrate reduction performance,achieving an ammonia yield of 382.48μmol g^(–1)h^(–1),5.7 times higher than that of pure COF.This work provides novel theoretical and practical insights into using controlled light intensity to regulate metal nanoparticle size within Schottky junctions,thereby enhancing photocatalytic nitrate reduction.展开更多
Cu-based electrocatalysts derived from copper oxide exhibit good electrocatalytic activity and selectivity in the electrocatalytic nitrate reduction reaction(NO_(3)RR).However,the origin of the enhanced selectivity an...Cu-based electrocatalysts derived from copper oxide exhibit good electrocatalytic activity and selectivity in the electrocatalytic nitrate reduction reaction(NO_(3)RR).However,the origin of the enhanced selectivity and activity of NO_(3)RR is unclear.Herein,we investigate the activity of three copper oxide/hydroxidederived catalysts,and verify the phase changes during the reduction process through electrochemical in situ Raman spectroscopy.Our results show that all phases ultimately transform into metallic copper during the electrochemical synthesis process,supporting that the zero valent copper phase is the actual active phase.The high-density grain boundaries and defects are responsible for the activity of NO_(3)RR.By combining with the nickel oxide,the selectivity of the catalyst for NO_(3)RR can be further improved,achieving an ammonia Faradaic efficiency of~96% and an ammonia yield of 3.2 mmol cm^(-2)h^(-1)at -0.05 V_(RHE).This experimental design of oxygen intercalation/elimination brings a more flexible electrode,which provides a new methodology for constructing the grain boundary toward NO_(3)RR.展开更多
Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites...Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.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
Electrochemical nitrate reduction reaction (NITRR) is regarded as a “two birds-one stone” method for the treatment of nitrate contaminant in polluted water and the synthesis of valuable ammonia, which is retarded by...Electrochemical nitrate reduction reaction (NITRR) is regarded as a “two birds-one stone” method for the treatment of nitrate contaminant in polluted water and the synthesis of valuable ammonia, which is retarded by the lack of highly reactive and selective electrocatalysts .Herein, for the first time, nickel foam supported Co_(4) N was designed as a high-performance NITRR catalyst by an in-situ nonmetal leaching-induced strategy.At the optimal potential, the Co_(4) N/NF catalyst achieves ultra-high Faraday efficiency and NH_(3) selectivity of 95.4% and 99.4%, respectively.Ex situ X-ray absorption spectroscopy (XAS), together with other experiments powerfully reveal that the nitrogen vacancies produced by nitrogen leaching are stable and play a key role in boosting nitrate reduction to ammonia.Theoretical calculations confirm that Co_(4) N with abundant nitrogen vacancies can optimize the adsorption energies of NO_(3)^(-) and intermediates, lower the free energy (Δ G ) of the potential-determining step (*NH_(3) to NH_(3) ) and inhibit the formation of N-containing byproducts.In addition, we also conclude that the nitrogen vacancies can stabilize the adsorbed hydrogen, making H_(2) quite difficult to produce, and lowering ΔG from *NO to *NOH, which facilitates the selective reduction of nitrate.This study reveals significant insights about the in-situ nonmetal leaching to enhance the NITRR activity.展开更多
Highly dispersed bimetallic alloy nanoparticle electrocatalysts have been demonstrated to exhibit exceptional performance in driving the nitrate reduction reaction(NO_(3)RR)to generate ammonia(NH_(3)).In this study,we...Highly dispersed bimetallic alloy nanoparticle electrocatalysts have been demonstrated to exhibit exceptional performance in driving the nitrate reduction reaction(NO_(3)RR)to generate ammonia(NH_(3)).In this study,we prepared mesoporous carbon nanofibers(mCNFs)functionalized with ordered PtFe alloys(O-PtFe-mCNFs)by a composite micelle interface-induced co-assembly method using poly(ethylene oxide)-block-polystyrene(PEO-b-PS)as a template.When employed as electrocatalysts,O-PtFe-mCNFs exhibited superior electrocatalytic performance for the NO_(3RR)compared to the mCNFs functionalized with disordered PtFe alloys(D-PtFe-mCNFs).Notably,the NH_(3)production performance was particularly outstanding,with a maximum NH_(3)yield of up to 959.6μmol/(h·cm~2).Furthermore,the Faraday efficiency(FE)was even 88.0%at-0.4 V vs.reversible hydrogen electrode(RHE).This finding provides compelling evidence of the potential of ordered PtFe alloy catalysts for the electrocatalytic NO_(3)RR.展开更多
Ammonia(NH_(3))is an irreplaceable chemical that has been widely demanded to keep the sustainable development of modern society.However,its industrial production consumes a huge amount of energy and releases extraordi...Ammonia(NH_(3))is an irreplaceable chemical that has been widely demanded to keep the sustainable development of modern society.However,its industrial production consumes a huge amount of energy and releases extraordinary greenhouse gases(GHGs),leading to various environmental issues.Achieving the green production of ammonia is a great challenge,which has been extensively pursued in the last decade.In this review,the most promising strategy,electrochemical nitrate reduction reaction(e-NO_(3)RR),is comprehensively investigated to give a complete understanding of its development and mechanism and provide guidance for future directions.However,owing to the complex reactions and limited selectivity,a comprehensive understanding of the mechanisms is crucial to further development and commercialization.Moreover,NO_(3)^(-)RR is a promising strategy for simultaneous water treatment and NH_(3)production.A detailed overview of the recent progress in NO_(3)^(-)RR for NH_(3)production with nontransition and transition metal based electrocatalysts is summarized.In addition,critical advanced techniques,future challenges,and prospects are discussed to guide future research on transition metal-based catalysts for commercial NH_(3)synthesis by NO_(3)^(-)reduction.展开更多
Ammonia(NH_(3))is an important raw material for modern agriculture and industry,being widely demanded to sustain the sustainable development of modern society.Currently,the industrial production methods of NH_(3),such...Ammonia(NH_(3))is an important raw material for modern agriculture and industry,being widely demanded to sustain the sustainable development of modern society.Currently,the industrial production methods of NH_(3),such as the traditional Haber-Bosch process,have drawbacks including high energy consumption and significant carbon dioxide emissions.In recent years,the electrocatalytic nitrate reduction reaction(NO_(3)RR)powered by intermittent renewable energy sources has gradually become a multidisciplinary research hotspot,as it allows for the efficient synthesis of NH_(3)under mild conditions.In this review,we focus on the research of electrocatalysts with atomic-level site,which have attracted attention due to their extremely high atomic utilization efficiency and unique structural characteristics in the field of NO_(3)RR.Firstly,we introduce the mechanism of nitrate reduction for ammonia synthesis and discuss the in-situ characterization techniques related to the mechanism study.Secondly,we review the progress of the electrocatalysts with atomic-level site for nitrate reduction and explore the structure-activity relationship to guide the rational design of efficient catalysts.Lastly,the conclusions of this review and the challenges and prospective of this promising field are presented.展开更多
Focusing on revealing the origin of high ammonia yield rate on Cu via nitrate reduction(NO3RR),we herein applied constant potential method via grand-canonical density functional theory(GC-DFT)with implicit continuum s...Focusing on revealing the origin of high ammonia yield rate on Cu via nitrate reduction(NO3RR),we herein applied constant potential method via grand-canonical density functional theory(GC-DFT)with implicit continuum solvation model to predict the reaction energetics of NO3RR on pure copper surface in alkaline media.The potential-dependent mechanism on the most prevailing Cu(111)and the minor(100)and(110)facets were established,in consideration of NO_(2)_(−),NO,NH_(3),NH_(2)OH,N_(2),and N_(2)O as the main products.The computational results show that the major Cu(111)is the ideal surface to produce ammonia with the highest onset potential at 0.06 V(until−0.37 V)and the highest optimal potential at−0.31 V for ammonia production without kinetic obstacles in activation energies at critical steps.For other minor facets,the secondary Cu(100)shows activity to ammonia from−0.03 to−0.54 V with the ideal potential at−0.50 V,which requires larger overpotential to overcome kinetic activation energy barriers.The least Cu(110)possesses the longest potential range for ammonia yield from−0.27 to−1.12 V due to the higher adsorption coverage of nitrate,but also with higher tendency to generate di-nitrogen species.Experimental evaluations on commercial Cu/C electrocatalyst validated the accuracy of our proposed mechanism.The most influential(111)surface with highest percentage in electrocatalyst determined the trend of ammonia production.In specific,the onset potential of ammonia production at 0.1 V and emergence of yield rate peak at−0.3 V in experiments precisely located in the predicted potentials on Cu(111).Four critical factors for the high ammonia yield and selectivity on Cu surface via NO3RR are summarized,including high NO3RR activity towards ammonia on the dominant Cu(111)facet,more possibilities to produce ammonia along different pathways on each facet,excellent ability for HER inhibition and suitable surface size to suppress di-nitrogen species formation at high nitrate coverage.Overall,our work provides comprehensive potential-dependent insights into the reaction details of NO3RR to ammonia,which can serve as references for the future development of NO3RR electrocatalysts,achieving higher activity and selectivity by maximizing these characteristics of copper-based materials.展开更多
基金National Natural Science Foundation of China (52371228, 52402045)fund of Key Laboratory of Advanced Materials of Ministry of Education(Advmat-2414)。
文摘Electrocatalytic nitrate reduction reaction (NO_(3)-RR) to ammonia under ambient conditions is expected to be a green process for ammonia synthesis and alleviate water pollution issues.We report a CuO nanoparticles incorporated on nitrogen-doped porous carbon (CuO@NC) catalyst for NO_(3)-RR.Part of Cu(Ⅱ) is reduced to Cu(Ⅰ) during the NO_(3)-RR process to construct Cu(Ⅰ)-Cu(Ⅱ) pairs,confirmed by in situ X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy.Density functional theory (DFT) calculations indicated that the formation of Cu(Ⅰ) could provide a reaction path with smaller energy barrier for NO_(3)-RR,while Cu(Ⅱ) effectively suppressed the competition of hydrogen evolution reaction (HER).As a result,CuO@NC catalyst achieved a Faradaic efficiency of 84.2% at -0.49 V versus reversible hydrogen electrode (RHE),and a NH_(3)yield rate of 17.2 mg h^(-1)mg^(-1)cat.at -0.79 V vs.RHE,higher than the HaberBosch process (<3.4 g h^(-1)g^(-1)cat.).This work may open a new avenue for effective NO_(3)-RR by modulating oxidation states.
基金supported by grants from the National Natural Science Foundation of China (22178339)2023 Innovation-driven Development Special Foundation of Guangxi(AA23023021)the Hundred Talents Program (A) of the Chinese Academy of Sciences
文摘Red mud(RM)is a solid waste generated in the aluminum industry after the extraction of alumina oxide;its multiple elements and higher pH value likely pose a severe threat to the environment after treatment.However,RM's higher concentrations of metal components,particularly Fe_(2)O_(3)and rare earth elements(REEs),render RM promising for catalytic application.Hence,this work showed an efficient high-speed RM to catalyze electrocatalytic nitrate-to-ammonia reduction reaction(NARR).RM calcined at 500℃(RM-500)exhibited excellent catalytic performance.Faradaic efficiency of ammonia(FENH_(3))in an electrolyte solution containing 1 mol·L^(-1)NO_(3)-achieved a maximum value of 92.3%at-0.8 V(vs.RHE).Additionally,24-h cycle testing and post-reaction PXRD and SEM indicated that the RM-500 electrocatalyst is stable during NARR.The RM-500 demonstrated a high FE of NH_(3)-to-NO_(3)-of 89.7%at 1.85 V(vs.RHE),showing great potential in the ammonia fuel cells technology and achieving the nitrogen cycle.
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.
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Project supported by the National Natural Science Foundation of China(21971129,21961022,21661023)the Inner Mongolia Autonomous Region 2022 Leading Talent Team of Science and Technology(2022LJRC0008)+5 种基金the Natural Science Foundation of Inner Mongolia Autonomous Region of China(2022MS02014,2021BS02007)the Program for Innovative Research Team in Universities of Inner Mongolia Autonomous Region(NJYT23031)the 111 Project(D20033)the"Grassland Leading Talent"Program of Inner Mongoliathe"Grassland-Talent"Innovation Team of Inner Mongoliathe"Science and Technology for A Better Development of Inner Mongolia"Program(2020XM03)。
文摘The excess emission of nitrate from human activities disturbs the global nitrogen cycle and thus needs to be remediated.In this work,we prepared a La-doped Co_(3)O_(4)nanoneedle arrays catalyst for highly efficient electrocatalytic reduction of NO_(3)^(-) to NH_(3)at low concentration.The La-doped Co_(3)O_(4)nanoneedle arrays exhibit remarkable activity with the highest Faradaic efficiency of 95.5%and an ammonia yield rate of 4.08 mg/(h·cm^(2))at-0.3 V versus RHE in 0.02 mol/L NO_(3)^(-).Experiments and theoretical calculations show that the La doping not only facilitates the surface reconstruction to form active La-Co(OH)_(2),but also inhibits the hydrogen evolution reaction over Co sites,thus promoting the NH_(3)production.This work provides new insights into the promoting effect of the rare earth elements in transition metalbased electrocatalyst for nitrate reduction.
基金supported by Shanghai Science and Technology Plan Project(No.23ZR1467000)the Fundamental Research Funds for the Central University(No.22120240354)+1 种基金the National Natural Science Foundation of China(No.22131004)the Leading Scientific Research Project from China National Nuclear Corporation(No.CNNC–CXLM-202205).
文摘The efficient electrocatalytic nitrate(NO_(3)^(−))reduction to ammonia(NRA)offers a sustainable alternative for both environmental remediation and ammonia synthesis.Developing advanced electrocatalysts with rationally designed spatial arrangement of active sites and optimizing the synergetic effect among components are crucial for high efficiency and selectivity.Herein,we present Fe/N active sites decorated on porous carbon nanofibers(CNFs)with encapsulated FeCo nanoparticles(FeCo@CNFs-Fe/N)as electrocatalysts for NRA.The FeCo@CNFs-Fe/N catalyst demonstrates exceptional performance,achieving a high ammonia yield of 498.18μmol/(h·g_(cat)).Meanwhile,the enhanced reduction activity,especially the reduction in overpotential by 0.565 V,is 3–10 times higher than that of FeCo-encapsulated and Fe/N-modified CNFs-based catalysts.The enhanced catalytic activity is attributed to the efficient structure design and optimized spatial distribution of active sites,which enhance the electron transfer rate and decrease the reaction energy barrier.Mechanistic studies reveal that the synergetic effect between encapsulated nanoparticles and surface-modified Fe/N sites plays a crucial role in promoting efficient nitrate adsorption and selective ammonia production.These findings highlight the potential of strategically engineered CNF-based composites for nitrate reduction and other advanced electrocatalytic applications.
基金support from the National Natural Science Foundation of China(Nos.52370100,52000146,and 51978098)China Postdoctoral Science Foundation(No.2020M673351).
文摘Catalytic reduction of nitrate over bimetallic catalysts has emerged as a technology for sustainable treatment of nitrate-containing groundwater.However,the structure of bimetallic has been much less investigated for catalyst optimization.Herein,two main types of Pd-Cu bimetallic nanocrystal structures,heterostructure and intermetallic,were prepared and characterized using high-resolution transmission electron microscopy(HRTEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The results show that two individual Pd and Cu nanocrystals with a mixed interface exist in the heterostructure nanocrystals,while Pd and Cu atoms are uniformly distributed across the intermetallic Pd-Cu nanocrystals.The catalytic nitrate reduction experiments were carried out in a semibatch reactor under constant hydrogen flow.The nitrate conversion rate of the heterostructure Pd-Cu nanocrystals supported onα-Al_(2)O_(3),γ-Al_(2)O_(3),SBA-15,and XC-72R exhibited 3.82-,6.76-,4.28-,2.44-fold enhancements relative to the intermetallic nanocrystals,and the nitrogen and nitrite were the main products for the heterostructure and intermetallic Pd-Cu nanocrystals,respectively.This indicates that the catalytic nitrate reduction over Pd-Cu catalyst is sensitive to the bimetallic structures of the catalysts,and heterostructure bimetallic nanocrystals exhibit better catalytic performances on both the activity and selectivity,which may provide new insights into the design and optimization of catalysts to improve catalytic activity and selectivity for nitrate reduction in water.
基金support from the National Natural Science Foundation of China(Nos.U21A2034 and 21876052)the Guangdong Special Support Plan for Innovation Teams(No.2019BT02L218)+1 种基金the Guangdong Special Support Plan for Young Top-notch Talents(No.2019TQ05L179)the Natural Science Foundation of Guangdong Province,China(No.2021B1515120077)。
文摘Electrochemical nitrate reduction(NO_(3)RR)offers a promising avenue for treating nitrate-contaminated water and recovering ammonia(NH_(3)),yet the complexities of direct electron transfer(DET)and hydrogen atom transfer(HAT)mechanisms crucial for efficiency remain elusive.This study bridges the gap with a combined experimental and theoretical approach,elucidating the impact of catalyst structure on NO3RR pathways.We discover that catalysts favoring strong NO_(3^(-))adsorption and efficient water dissociation were more inclined towards DET,enhancing denitrification.The Fe@Fe_(3)O_(4)/FF cathode,leveraging the synergistic interplay between metallic Fe and Fe_(3)O_(4),excelled in NO3RR via DET,achieving an NH3yield of 0.28 mmol h-1cm-2and a Faradaic efficiency of 95.7%for NH3at-1.6 V(vs.SCE),with minimal nitrite accumulation at 100 mmol/L nitrate.Conversely,the Fe/FF and Fe_(3)O_(4)/CC cathodes showed reduced NH3production and increased nitrite levels,attributed to the lack of Fe_(3)O_(4)and metallic Fe,respectively,resulting in a dominant HAT mechanism.Moreover,Fe@Fe_(3)O_(4)/FF facilitated complete denitrification in real wastewater treatment by harnessing Cl^(-)for electrochemically mediated breakpoint chlorination.This research not only deepens our understanding of NO3RR mechanisms but also paves the way for designing superior nitrate reduction catalysts.
基金supported by the National Natural Science Foundation of China(12205300(H.S.),12405377(M.H.L))the Postdoctoral Science Foundation of China(2024M763694(M.H.L))+3 种基金the Natural Science Foundation of Hunan Province(2024JJ4027(H.S.))the Postdoctoral Fellowship Program of CPSF under Grant Number GZB20240859(M.H.L)financial support from the Hunan Normal University Program(grant05311204666)financial support from the 2024 Large Instrument Testing Open Fund of Hunan Normal University(24CSY033,24CSY086)。
文摘The electrochemical conversion of nitrate,a widespread water pollutant,into valuable ammonia represents a green and decentralized approach to ammonia synthesis.However,the sluggish multielectronproton coupling path and the low reactive species(nitrate and proton)concentration at the catalyst interface inhibit the efficiency of ammonia production from nitrate reduction reaction(NitRR).Herein,we introduce a novel iron-based tandem catalyst encapsulated by reduced graphene oxide(denoted as Fe-rGO),with a superior ammonia production rate of 47.815 mg h^(-1)mg_(ca)^(t-1)and a high Faraday efficiency(FE)of 96.51%at an applied potential of-0.5 V.It also delivers a robust stability with FE above90%under a current density of 250 mA cm^(-2)for 50 h.In situ X-ray absorption spectroscopy reveals that the FeO_(x)is dynamically translated to Fe~0 site concurrently with the enhancement of the NH_(3)production rate,suggesting the Fe^(0) site as hydrogenation active center.The asymmetric distribution of surface charges of rGO not only enriches nitrate ions at the catalytic interface and promotes the hydrogenation process in NitRR,but also protects the iron species and ensures their stability during electrolysis.The Zn-NO_(3)^(-)battery demonstrates an impressive FE of 88.6%,highlighting its exceptional potential for practical applications.
基金financially supported by the National Natural Science Foundation of China(22179035)the Science Fund for Distinguished Young Scholars of Heilongjiang Province(JQ2022B001)the Fundamental Research Funds for the Universities of Heilongjiang Province of China(2023-KYYWF1440)。
文摘Electrocatalytic nitrate reduction reaction(NitRR)utilizing water as a hydrogen source under ambient conditions represents a highly promising avenue for sustainable ammonia synthesis and environmental remediation.However,achieving high efficiency and selectivity in NitRR is fundamentally challenged by the complex lifecycle management of active hydrogen derived from water splitting.This review provides a timely and comprehensive analysis centered on the pivotal role and meticulous regulation of active hydrogen throughout the NitRR process.We first elucidate the distinct functions and characteristics of various hydrogen species,followed by a survey of advanced characterization techniques crucial for monitoring the dynamics of active hydrogen.Critically,three core strategies were systematically dissected to modulate the active hydrogen lifecycle:accelerating water activation and dissociation,enhancing the directional transport of hydrogen species,and precisely tuning active hydrogen coupling pathways while suppressing parasitic hydrogen evolution.By consolidating current understanding from both catalyst design and reaction mechanism perspectives,this review offers a hydrogen-centric roadmap and highlights emerging opportunities for rationally engineering advanced NitRR systems.
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).
文摘Nitrate pollution poses a significant environmental challenge,and photocatalytic nitrate reduction has garnered considerable attention due to its efficiency and environmental advantages.Among these,the development of Schottky junctions shows considerable potential for practical applications.However,the impact of metal nanoparticle size within Schottky junctions on photocatalytic nitrate reduction remains largely unexplored.In this study,we propose a novel method to modulate metal nanoparticle size within Schottky junctions by controlling light intensity during the photodeposition process.Smaller Au nanoparticles were found to enhance electron accumulation at active sites by promoting charge transfer from COF to Au,thereby improving internal electron transport.Additionally,the Schottky barrier effectively suppressed reverse electron transfer while enhancing NO_(3)^(–)adsorption and activation.The Au_(2-)COF exhibited remarkable nitrate reduction performance,achieving an ammonia yield of 382.48μmol g^(–1)h^(–1),5.7 times higher than that of pure COF.This work provides novel theoretical and practical insights into using controlled light intensity to regulate metal nanoparticle size within Schottky junctions,thereby enhancing photocatalytic nitrate reduction.
基金supported by the National Science and Technology Major Project(2022YFA1205200)the National Natural Science Foundation of China(22269016,22479083,22405138)the Group Project of Developing Inner Mongolia through Talents from the Talents Work Leading Group under the CPC Inner Mongolia Autonomous Regional Committee(2025TYL03)。
文摘Cu-based electrocatalysts derived from copper oxide exhibit good electrocatalytic activity and selectivity in the electrocatalytic nitrate reduction reaction(NO_(3)RR).However,the origin of the enhanced selectivity and activity of NO_(3)RR is unclear.Herein,we investigate the activity of three copper oxide/hydroxidederived catalysts,and verify the phase changes during the reduction process through electrochemical in situ Raman spectroscopy.Our results show that all phases ultimately transform into metallic copper during the electrochemical synthesis process,supporting that the zero valent copper phase is the actual active phase.The high-density grain boundaries and defects are responsible for the activity of NO_(3)RR.By combining with the nickel oxide,the selectivity of the catalyst for NO_(3)RR can be further improved,achieving an ammonia Faradaic efficiency of~96% and an ammonia yield of 3.2 mmol cm^(-2)h^(-1)at -0.05 V_(RHE).This experimental design of oxygen intercalation/elimination brings a more flexible electrode,which provides a new methodology for constructing the grain boundary toward NO_(3)RR.
基金the financial support from the Natural Science Foundation of China(Grant No.52172106)Anhui Provincial Natural Science Foundation(Grant Nos.2108085QB60 and 2108085QB61)China Postdoctoral Science Foundation(Grant Nos.2020M682057 and 2023T160651).
文摘Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.
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financial supports from National Natural Science Foundation of China(Nos.91741105,22006120)Program for Innovation Team Building at Institutions of Higher Education in Chongqing(No.CXTDX201601011)Chongqing Municipal Natural Science Foundation(No.cstc2018jcyjAX0625).
文摘Electrochemical nitrate reduction reaction (NITRR) is regarded as a “two birds-one stone” method for the treatment of nitrate contaminant in polluted water and the synthesis of valuable ammonia, which is retarded by the lack of highly reactive and selective electrocatalysts .Herein, for the first time, nickel foam supported Co_(4) N was designed as a high-performance NITRR catalyst by an in-situ nonmetal leaching-induced strategy.At the optimal potential, the Co_(4) N/NF catalyst achieves ultra-high Faraday efficiency and NH_(3) selectivity of 95.4% and 99.4%, respectively.Ex situ X-ray absorption spectroscopy (XAS), together with other experiments powerfully reveal that the nitrogen vacancies produced by nitrogen leaching are stable and play a key role in boosting nitrate reduction to ammonia.Theoretical calculations confirm that Co_(4) N with abundant nitrogen vacancies can optimize the adsorption energies of NO_(3)^(-) and intermediates, lower the free energy (Δ G ) of the potential-determining step (*NH_(3) to NH_(3) ) and inhibit the formation of N-containing byproducts.In addition, we also conclude that the nitrogen vacancies can stabilize the adsorbed hydrogen, making H_(2) quite difficult to produce, and lowering ΔG from *NO to *NOH, which facilitates the selective reduction of nitrate.This study reveals significant insights about the in-situ nonmetal leaching to enhance the NITRR activity.
基金National Natural Science Foundation of China(Nos.52225204,52173233 and 52202085)Innovation Program of Shanghai Municipal Education Commission,China(No.2021-01-07-00-03-E00109)+3 种基金Natural Science Foundation of Shanghai,China(No.23ZR1479200)“Shuguang Program”Supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission,China(No.20SG33)Fundamental Research Funds for the Central Universities,China(No.2232024Y-01)DHU Distinguished Young Professor Program,China(Nos.LZA2022001 and LZB2023002)。
文摘Highly dispersed bimetallic alloy nanoparticle electrocatalysts have been demonstrated to exhibit exceptional performance in driving the nitrate reduction reaction(NO_(3)RR)to generate ammonia(NH_(3)).In this study,we prepared mesoporous carbon nanofibers(mCNFs)functionalized with ordered PtFe alloys(O-PtFe-mCNFs)by a composite micelle interface-induced co-assembly method using poly(ethylene oxide)-block-polystyrene(PEO-b-PS)as a template.When employed as electrocatalysts,O-PtFe-mCNFs exhibited superior electrocatalytic performance for the NO_(3RR)compared to the mCNFs functionalized with disordered PtFe alloys(D-PtFe-mCNFs).Notably,the NH_(3)production performance was particularly outstanding,with a maximum NH_(3)yield of up to 959.6μmol/(h·cm~2).Furthermore,the Faraday efficiency(FE)was even 88.0%at-0.4 V vs.reversible hydrogen electrode(RHE).This finding provides compelling evidence of the potential of ordered PtFe alloy catalysts for the electrocatalytic NO_(3)RR.
基金supported by the National Natural Science Foundation of China(Grant Nos.22050410268,22176131)Shenzhen Basic Research General Project(JCYJ20210324095205015,JCYJ20220818095601002)。
文摘Ammonia(NH_(3))is an irreplaceable chemical that has been widely demanded to keep the sustainable development of modern society.However,its industrial production consumes a huge amount of energy and releases extraordinary greenhouse gases(GHGs),leading to various environmental issues.Achieving the green production of ammonia is a great challenge,which has been extensively pursued in the last decade.In this review,the most promising strategy,electrochemical nitrate reduction reaction(e-NO_(3)RR),is comprehensively investigated to give a complete understanding of its development and mechanism and provide guidance for future directions.However,owing to the complex reactions and limited selectivity,a comprehensive understanding of the mechanisms is crucial to further development and commercialization.Moreover,NO_(3)^(-)RR is a promising strategy for simultaneous water treatment and NH_(3)production.A detailed overview of the recent progress in NO_(3)^(-)RR for NH_(3)production with nontransition and transition metal based electrocatalysts is summarized.In addition,critical advanced techniques,future challenges,and prospects are discussed to guide future research on transition metal-based catalysts for commercial NH_(3)synthesis by NO_(3)^(-)reduction.
基金financial support from the Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX24_0690)financial support from the National Natural Science Foundation of China (Project No. 22275088, 52101260)+4 种基金the Project of Shuangchuang Scholar of Jiangsu Province (Project No. JSSCBS20210212)the Fundamental Research Funds for the Central Universities (Project No. 30921011203)the Start-Up Grant (Project No. AE89991/340) from Nanjing University of Science and Technologyfinancial support from the Foundation of Jiangsu Educational Committee (22KJB310008)the Senior Talent Program of Jiangsu University (20JDG073)
文摘Ammonia(NH_(3))is an important raw material for modern agriculture and industry,being widely demanded to sustain the sustainable development of modern society.Currently,the industrial production methods of NH_(3),such as the traditional Haber-Bosch process,have drawbacks including high energy consumption and significant carbon dioxide emissions.In recent years,the electrocatalytic nitrate reduction reaction(NO_(3)RR)powered by intermittent renewable energy sources has gradually become a multidisciplinary research hotspot,as it allows for the efficient synthesis of NH_(3)under mild conditions.In this review,we focus on the research of electrocatalysts with atomic-level site,which have attracted attention due to their extremely high atomic utilization efficiency and unique structural characteristics in the field of NO_(3)RR.Firstly,we introduce the mechanism of nitrate reduction for ammonia synthesis and discuss the in-situ characterization techniques related to the mechanism study.Secondly,we review the progress of the electrocatalysts with atomic-level site for nitrate reduction and explore the structure-activity relationship to guide the rational design of efficient catalysts.Lastly,the conclusions of this review and the challenges and prospective of this promising field are presented.
基金supported by is supported by the Shanghai Municipal Science and Technology Major Projectthe support from Shanghai Super Postdoctoral Incentive Program
文摘Focusing on revealing the origin of high ammonia yield rate on Cu via nitrate reduction(NO3RR),we herein applied constant potential method via grand-canonical density functional theory(GC-DFT)with implicit continuum solvation model to predict the reaction energetics of NO3RR on pure copper surface in alkaline media.The potential-dependent mechanism on the most prevailing Cu(111)and the minor(100)and(110)facets were established,in consideration of NO_(2)_(−),NO,NH_(3),NH_(2)OH,N_(2),and N_(2)O as the main products.The computational results show that the major Cu(111)is the ideal surface to produce ammonia with the highest onset potential at 0.06 V(until−0.37 V)and the highest optimal potential at−0.31 V for ammonia production without kinetic obstacles in activation energies at critical steps.For other minor facets,the secondary Cu(100)shows activity to ammonia from−0.03 to−0.54 V with the ideal potential at−0.50 V,which requires larger overpotential to overcome kinetic activation energy barriers.The least Cu(110)possesses the longest potential range for ammonia yield from−0.27 to−1.12 V due to the higher adsorption coverage of nitrate,but also with higher tendency to generate di-nitrogen species.Experimental evaluations on commercial Cu/C electrocatalyst validated the accuracy of our proposed mechanism.The most influential(111)surface with highest percentage in electrocatalyst determined the trend of ammonia production.In specific,the onset potential of ammonia production at 0.1 V and emergence of yield rate peak at−0.3 V in experiments precisely located in the predicted potentials on Cu(111).Four critical factors for the high ammonia yield and selectivity on Cu surface via NO3RR are summarized,including high NO3RR activity towards ammonia on the dominant Cu(111)facet,more possibilities to produce ammonia along different pathways on each facet,excellent ability for HER inhibition and suitable surface size to suppress di-nitrogen species formation at high nitrate coverage.Overall,our work provides comprehensive potential-dependent insights into the reaction details of NO3RR to ammonia,which can serve as references for the future development of NO3RR electrocatalysts,achieving higher activity and selectivity by maximizing these characteristics of copper-based materials.
