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
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
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
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
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
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
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
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
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
The electrocatalytic nitrate reduction reaction (NO_(3)RR) powered by renewable energy offers a promising approach for simultaneously reutilization of nitrate and synthesizing high-value products.Nevertheless,theoreti...The electrocatalytic nitrate reduction reaction (NO_(3)RR) powered by renewable energy offers a promising approach for simultaneously reutilization of nitrate and synthesizing high-value products.Nevertheless,theoretical understanding of reaction mechanism was relative illusive,which is indispensable to rationally design of efficient catalysts.Besides,tuning the reaction microenvironment along with the scale-up device development is essential to promote the industrial deployment of electrocatalytic nitrate conversion,while relative research was overlooked.In this regard,recent advances in ammonia synthesis are firstly summarized,including the identification of active sites,exploration of the underlying reaction mechanisms,electrolyzer design and technical-economic analysis.Furthermore,electrocatalytic C–N coupling based on NO_(3)RR to produce higher-value products such as urea and amino acids are also reviewed,to extend the application potential and economic feasibility.Finally,we highlight the existing challenges and the demand of future research for NO_(3)RR.This review anticipates to provide insights into synthesis of high-value products via NO_(3)RR,bridging the gap from laboratory research to industrial fabrication.展开更多
Electrochemical nitrate reduction to NH_(3)holds a great promise for N-upcycling in nature,while its sluggish reaction kinetics involved in both the stepwise deoxygenation and hydrogenation processes necessitates the ...Electrochemical nitrate reduction to NH_(3)holds a great promise for N-upcycling in nature,while its sluggish reaction kinetics involved in both the stepwise deoxygenation and hydrogenation processes necessitates the development of bespoke catalysts with multi-site engineering.Herein,we report a hybrid catalyst composed of rare-earth(RE)yttrium(Y)single atoms and copper phosphide(Cu_(3)P)nanoparticles loaded on N,P-doped carbon(Y_(SA)-Cu_(3)P/CNP)through a chelating and pyrolysis method.Owing to a synergistic contribution of Y single atoms and Cu_(3)P nanoparticles,Y_(SA)-Cu_(3)P/CNP achieves an impressive NH_(3)Faradaic efficiency(FE)of 92%at-0.5V(vs.RHE)and the highest NH_(3)yield rate of11.4 mg·h^(-1)·cm^(-2)at-0.6 V(vs.RHE)in an alkaline media,which surpass most of the reported electrocatalysts.The intricate reaction pathway has been explored by online differential electrochemical mass spectrometry(DEMS),and the synergistic effect between Y single atoms and Cu_(3)P nanoparticles has been studied by in situ synchrotron X-ray absorption spectroscopy.Moreover,density-functional theory(DFT)calculations unveil that the high-efficiency nitrate reduction on Y_(SA)-Cu_(3)P/CNP is attributed to a reduced energy barrier of the rate-determining deoxygenation step coupled with the enhanced stabilization of active hydrogen favorable for the hydrogenation steps,thereby boosting the overall reaction rates.In addition,a prototype Zn-nitrate battery utilizing Y_(SA)-Cu_(3)P/CNP as the cathode is unveiled.This work not only elucidates the mechanism behind the enhanced catalytic performance but also paves the way for the future development of highefficiency electrocatalysts through dual-site engineering.展开更多
The nitrate reduction reaction(NtRR)has been demonstrated to be a promising way for obtaining ammonia(NH_(3))by converting NO3-to NH3.Here we report the controlled synthesis of cobalt tetroxide/graphdiyne heterostruct...The nitrate reduction reaction(NtRR)has been demonstrated to be a promising way for obtaining ammonia(NH_(3))by converting NO3-to NH3.Here we report the controlled synthesis of cobalt tetroxide/graphdiyne heterostructured nanowires(Co_(3)O_(4)/GDY NWs)by a simple two-step process including the synthesis of Co_(3)O_(4)NWs and the following growth of GDY using hex-aethynylbenzene as the precursor at 110°C for 10 h.Detailed scanning electron microscopy,high resolution transmission electron microscopy,X-ray photoelectron spectroscopy,and Raman characterization confirmed the synthesis of a Co_(3)O_(4)/GDY heterointerface with the formation of sp-C-Co bonds at the interface and incomplete charge transfer between GDY and Co,which provide a con-tinuous supply of electrons for the catalytic reaction and ensure a rapid NtRR.Because of these advantages,Co_(3)O_(4)/GDY NWs had an excellent NtRR performance with a high NH3 yield rate(YNH3)of 0.78 mmol h^(-1)cm^(-2)and a Faraday efficiency(FE)of 92.45%at-1.05 V(vs.RHE).This work provides a general approach for synthesizing heterostructures that can drive high-performance ammo-nia production from wastewater under ambient conditions.展开更多
Cu-based materials are commonly used in electrocatalytic nitrate reduction reactions(NO 3 RR).NO 3 RR is a“two birds,one stone”approach,simultaneously removing NO 3−pollutants and producing valuable ammonia(NH 3).Ho...Cu-based materials are commonly used in electrocatalytic nitrate reduction reactions(NO 3 RR).NO 3 RR is a“two birds,one stone”approach,simultaneously removing NO 3−pollutants and producing valuable ammonia(NH 3).However,the strong coordination between the NO 3−intermediate and the catalytic active sites seriously hinders the conversion effi ciency.Here,we determined that,through encapsulation strategies,the carbon layer could weaken the NO 3−intermediate binding to active sites,resulting in higher NH 3 yields.We experimentally fabricated electrocatalysts,i.e.,Cu nanoparticles encapsulating(or loaded on)N-doped carbon nanofi bers(NCNFs)called Cu@NCNFs(Cu-NCNFs),using electrostatic spinning.As a result,Cu@NCNFs can achieve NH 3 yields of 17.08 mg/(h·mg cat)at a voltage of−0.84 V and a Faraday effi ciency of 98.15%.Meanwhile,the electrochemical properties of the Cu nanoparticles on the surface of carbon fi bers(Cu-NCNFs)are lower than those of the Cu@NCNFs.The in situ Raman spectra of Cu@NCNFs and Cu-NCNFs under various reduction potentials during the NO 3 RR process show that catalyst encapsulation within carbon layers can eff ectively reduce the adsorption of N species by the catalyst,thus improving the catalytic performance in the nitrate-to-ammonia catalytic conversion process.展开更多
Electrochemical-nitrate-reduction-reaction(eNitRR)synthesis of ammonia is an effective way to treat ni-trate wastewater and alleviate the pressure of the Haber-Bosch ammonia production industry.How to develop effectiv...Electrochemical-nitrate-reduction-reaction(eNitRR)synthesis of ammonia is an effective way to treat ni-trate wastewater and alleviate the pressure of the Haber-Bosch ammonia production industry.How to develop effective catalysts to electrochemically reduce nitrate to ammonia and purify sewage under com-plex environmental conditions is the focus of current research.Herein,the dopamine polymerization pro-cess and the[(C_(12)H_(8)N_(2))_(2)Cu]^(2+)complex embedding process were run simultaneously in time and space,and ultrafine Cu nanoparticles(Cu/CN)were effectively loaded on nitrogen-doped carbon after heat treat-ment.Using Cu/CN as the catalyst,the ammonia yield rate and Faradaic efficiency of the electrochemical conversion of NO_(3)^(-)to NH_(3)are highly 8984.0μg h^(−1)mg cat.^(−1)and 95.6%,respectively.Even in the face of complex water environments,such as neutral media,acidic media,coexisting ions,and actual nitrate wastewater,nitrate wastewater can be effectively purified to form high value-added ammonia.The strat-egy of simultaneous embedding increases the exposure rate of Cu sites,and the support of CN is also beneficial to reduce the energy barrier of ^(∗)NO_(3)activation.This study rationally designed catalysts that are beneficial to eNitRR,and considered the situation faced by practical applications during the research stage,reducing the performance gap between laboratory exploration and industrial applications.展开更多
Nitrate(NO_(3)^(−))electroreduction reaction(NO_(3)^(−)RR)provides an attractive and sustainable route for NO_(3)^(−)pollution mitigation or energy-saved ammonia(NH3)synthesis.In this work,high-quality B and Fe co-dop...Nitrate(NO_(3)^(−))electroreduction reaction(NO_(3)^(−)RR)provides an attractive and sustainable route for NO_(3)^(−)pollution mitigation or energy-saved ammonia(NH3)synthesis.In this work,high-quality B and Fe co-doped Co_(2) P hollow nanocubes(B/Fe-Co_(2) P HNCs)are successfully synthesized though simultaneous boronation-phosphorization treatment,which reveal outstanding selectivity,activity,stability for the NO_(3)^(−)to NH_(3) conversion in neutral electrolyte because of big surface area,fast mass transport,superhydrophilic surface,and optimized electronic structure.B/Fe-Co_(2) P HNCs can achieve the high NH3 yield rate(22.67 mg h^(−1) mg_(cat)^(−1))as well as Faradaic efficiency(97.54%)for NO_(3)^(−)RR,greatly outperforming most of non-precious metal based NO_(3)^(−)RR electrocatalysts.展开更多
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 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.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the support from Key R&D Program of Zhejiang(2024SSYS0064)the Fundamental Research Funds for the Central Universities (2022ZFJH04)。
文摘The electrocatalytic nitrate reduction reaction (NO_(3)RR) powered by renewable energy offers a promising approach for simultaneously reutilization of nitrate and synthesizing high-value products.Nevertheless,theoretical understanding of reaction mechanism was relative illusive,which is indispensable to rationally design of efficient catalysts.Besides,tuning the reaction microenvironment along with the scale-up device development is essential to promote the industrial deployment of electrocatalytic nitrate conversion,while relative research was overlooked.In this regard,recent advances in ammonia synthesis are firstly summarized,including the identification of active sites,exploration of the underlying reaction mechanisms,electrolyzer design and technical-economic analysis.Furthermore,electrocatalytic C–N coupling based on NO_(3)RR to produce higher-value products such as urea and amino acids are also reviewed,to extend the application potential and economic feasibility.Finally,we highlight the existing challenges and the demand of future research for NO_(3)RR.This review anticipates to provide insights into synthesis of high-value products via NO_(3)RR,bridging the gap from laboratory research to industrial fabrication.
基金financially supported by the National Key Research and Development Program of China(Nos.2022YFA1505700 and 2019YFA0210403)the National Natural Science Foundation of China(Nos.22205232 and 21601187)+2 种基金the Talent Plan of Shanghai Branch,Chinese Academy of Sciences(No.CASSHB-QNPD-2023-020)the Natural Science Foundation of Fujian Province(Nos.2023J06044 and 2023J01213)the Fund for Distinguished Young Scholars of FJIRSM(No.CXZX-2022-JQ06)。
文摘Electrochemical nitrate reduction to NH_(3)holds a great promise for N-upcycling in nature,while its sluggish reaction kinetics involved in both the stepwise deoxygenation and hydrogenation processes necessitates the development of bespoke catalysts with multi-site engineering.Herein,we report a hybrid catalyst composed of rare-earth(RE)yttrium(Y)single atoms and copper phosphide(Cu_(3)P)nanoparticles loaded on N,P-doped carbon(Y_(SA)-Cu_(3)P/CNP)through a chelating and pyrolysis method.Owing to a synergistic contribution of Y single atoms and Cu_(3)P nanoparticles,Y_(SA)-Cu_(3)P/CNP achieves an impressive NH_(3)Faradaic efficiency(FE)of 92%at-0.5V(vs.RHE)and the highest NH_(3)yield rate of11.4 mg·h^(-1)·cm^(-2)at-0.6 V(vs.RHE)in an alkaline media,which surpass most of the reported electrocatalysts.The intricate reaction pathway has been explored by online differential electrochemical mass spectrometry(DEMS),and the synergistic effect between Y single atoms and Cu_(3)P nanoparticles has been studied by in situ synchrotron X-ray absorption spectroscopy.Moreover,density-functional theory(DFT)calculations unveil that the high-efficiency nitrate reduction on Y_(SA)-Cu_(3)P/CNP is attributed to a reduced energy barrier of the rate-determining deoxygenation step coupled with the enhanced stabilization of active hydrogen favorable for the hydrogenation steps,thereby boosting the overall reaction rates.In addition,a prototype Zn-nitrate battery utilizing Y_(SA)-Cu_(3)P/CNP as the cathode is unveiled.This work not only elucidates the mechanism behind the enhanced catalytic performance but also paves the way for the future development of highefficiency electrocatalysts through dual-site engineering.
文摘The nitrate reduction reaction(NtRR)has been demonstrated to be a promising way for obtaining ammonia(NH_(3))by converting NO3-to NH3.Here we report the controlled synthesis of cobalt tetroxide/graphdiyne heterostructured nanowires(Co_(3)O_(4)/GDY NWs)by a simple two-step process including the synthesis of Co_(3)O_(4)NWs and the following growth of GDY using hex-aethynylbenzene as the precursor at 110°C for 10 h.Detailed scanning electron microscopy,high resolution transmission electron microscopy,X-ray photoelectron spectroscopy,and Raman characterization confirmed the synthesis of a Co_(3)O_(4)/GDY heterointerface with the formation of sp-C-Co bonds at the interface and incomplete charge transfer between GDY and Co,which provide a con-tinuous supply of electrons for the catalytic reaction and ensure a rapid NtRR.Because of these advantages,Co_(3)O_(4)/GDY NWs had an excellent NtRR performance with a high NH3 yield rate(YNH3)of 0.78 mmol h^(-1)cm^(-2)and a Faraday efficiency(FE)of 92.45%at-1.05 V(vs.RHE).This work provides a general approach for synthesizing heterostructures that can drive high-performance ammo-nia production from wastewater under ambient conditions.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.22208048,22202174,62001097 and 21576238)the Natural Science Foundation of Heilongjiang Province(No.YQ2022B001)We would like to acknowledge the technical support from Analysis and Testing Center of Northeast Forestry University.
文摘Cu-based materials are commonly used in electrocatalytic nitrate reduction reactions(NO 3 RR).NO 3 RR is a“two birds,one stone”approach,simultaneously removing NO 3−pollutants and producing valuable ammonia(NH 3).However,the strong coordination between the NO 3−intermediate and the catalytic active sites seriously hinders the conversion effi ciency.Here,we determined that,through encapsulation strategies,the carbon layer could weaken the NO 3−intermediate binding to active sites,resulting in higher NH 3 yields.We experimentally fabricated electrocatalysts,i.e.,Cu nanoparticles encapsulating(or loaded on)N-doped carbon nanofi bers(NCNFs)called Cu@NCNFs(Cu-NCNFs),using electrostatic spinning.As a result,Cu@NCNFs can achieve NH 3 yields of 17.08 mg/(h·mg cat)at a voltage of−0.84 V and a Faraday effi ciency of 98.15%.Meanwhile,the electrochemical properties of the Cu nanoparticles on the surface of carbon fi bers(Cu-NCNFs)are lower than those of the Cu@NCNFs.The in situ Raman spectra of Cu@NCNFs and Cu-NCNFs under various reduction potentials during the NO 3 RR process show that catalyst encapsulation within carbon layers can eff ectively reduce the adsorption of N species by the catalyst,thus improving the catalytic performance in the nitrate-to-ammonia catalytic conversion process.
基金supported by the Zhejiang Province Key Research and Development Project(No.2023C01191)the Construction of the Scientific Research Platform of Yunnan Normal University(No.01100205020503202)+1 种基金the“Union University Innovation Team”of Yunnan Normal University(No.01100205020503209)the“Spring City Plan:the High-level Talent Promotion and Training Project of Kunming(No.2022SCP005)”.
文摘Electrochemical-nitrate-reduction-reaction(eNitRR)synthesis of ammonia is an effective way to treat ni-trate wastewater and alleviate the pressure of the Haber-Bosch ammonia production industry.How to develop effective catalysts to electrochemically reduce nitrate to ammonia and purify sewage under com-plex environmental conditions is the focus of current research.Herein,the dopamine polymerization pro-cess and the[(C_(12)H_(8)N_(2))_(2)Cu]^(2+)complex embedding process were run simultaneously in time and space,and ultrafine Cu nanoparticles(Cu/CN)were effectively loaded on nitrogen-doped carbon after heat treat-ment.Using Cu/CN as the catalyst,the ammonia yield rate and Faradaic efficiency of the electrochemical conversion of NO_(3)^(-)to NH_(3)are highly 8984.0μg h^(−1)mg cat.^(−1)and 95.6%,respectively.Even in the face of complex water environments,such as neutral media,acidic media,coexisting ions,and actual nitrate wastewater,nitrate wastewater can be effectively purified to form high value-added ammonia.The strat-egy of simultaneous embedding increases the exposure rate of Cu sites,and the support of CN is also beneficial to reduce the energy barrier of ^(∗)NO_(3)activation.This study rationally designed catalysts that are beneficial to eNitRR,and considered the situation faced by practical applications during the research stage,reducing the performance gap between laboratory exploration and industrial applications.
基金supported by Natural Science Foundation of Shanxi Province(No.202203021222213)Taiyuan University of Science and Technology Scientific Research Initial Funding(No.20222091)+2 种基金National Natural Science Foundation of China(No.22073061)Science and Technology Innovation Team of Shaanxi Province(No.2023-CX-TD-27)Fundamental Research Funds for the Central Universities(No.GK202202001).
文摘Nitrate(NO_(3)^(−))electroreduction reaction(NO_(3)^(−)RR)provides an attractive and sustainable route for NO_(3)^(−)pollution mitigation or energy-saved ammonia(NH3)synthesis.In this work,high-quality B and Fe co-doped Co_(2) P hollow nanocubes(B/Fe-Co_(2) P HNCs)are successfully synthesized though simultaneous boronation-phosphorization treatment,which reveal outstanding selectivity,activity,stability for the NO_(3)^(−)to NH_(3) conversion in neutral electrolyte because of big surface area,fast mass transport,superhydrophilic surface,and optimized electronic structure.B/Fe-Co_(2) P HNCs can achieve the high NH3 yield rate(22.67 mg h^(−1) mg_(cat)^(−1))as well as Faradaic efficiency(97.54%)for NO_(3)^(−)RR,greatly outperforming most of non-precious metal based NO_(3)^(−)RR electrocatalysts.
