Ammonia plays a crucial role in contemporary society,impacting medicine,agriculture,and the chemical industry.The conventional industrial synthesis of NH_(3) through the Haber-Bosch technique,carried out under severe ...Ammonia plays a crucial role in contemporary society,impacting medicine,agriculture,and the chemical industry.The conventional industrial synthesis of NH_(3) through the Haber-Bosch technique,carried out under severe reaction conditions,leads to substantial energy consumption and environmental pollution.It is thus imperative for NH_(3) synthesis methods to be investigated under more favorable conditions.Synthesis of ammonia by electrocatalysis can effectively reduce the environmental damage and other urgent problems,which is a promising solution.Metal-nitrogen series batteries(M-N batteries),such as metal-nitrogen gas batteries,metal-nitrogen oxide batteries and metal-oxynitride batteries have been regarded recently as an exemplar of concurrent NH_(3) synthesis and energy production.Nonetheless,the large-scale application of these batteries is still limited by numerous challenges are currently existing in building high-efficiency M-N batteries,including poor Faradic efficiency and low NH_(3) yield.Therefore,a comprehensive overview of M-N batteries is offered,specifically focusing on advanced strategies for designing highly efficient cathode catalysts in anticipation of future developments.The metal anodes,cathodic electro-reduction reactions,and design principles are encompassed in the discussion,offering detailed insights to enhance understanding.Mechanisms,feasibility analyses,technoeconomic assessments,device combinations,and comparative evaluations are delved into in the review,contributing to a thorough comprehension of diverse systems and their application potential.Perspectives and opportunities for future research directions are also delineated.展开更多
The electrochemical coupling of biomass oxidation and nitrogen conversion presents a potential strategy for high value-added chemicals and nitrogen cycling.Herein,in this work,CuO/Co_(3)O_(4)with heterogeneous interfa...The electrochemical coupling of biomass oxidation and nitrogen conversion presents a potential strategy for high value-added chemicals and nitrogen cycling.Herein,in this work,CuO/Co_(3)O_(4)with heterogeneous interface is successfully constructed as a bifunctional catalyst for the electrooxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid and the electroreduction of nitrate to ammonia(NH_(3)).The open-circuit potential spontaneous experiment shows that more 5-hydroxymethylfurfural molecules are adsorbed in the Helmholtz layer of the CuO/Co_(3)O_(4)composite,which certifies that the CuO/Co_(3)O_(4)heterostructure is conducive to the kinetic adsorption of 5-hydroxymethylfurfural.In situ electrochemical impedance spectroscopy further shows that CuO/Co_(3)O_(4)has faster reaction kinetics and lower reaction potential in oxygen evolution reaction and 5-hydroxymethylfurfural electrocatalytic oxidation.Moreover,CuO/Co_(3)O_(4)also has a good reduction effect on NO_(3)^(-).The ex-situ Raman spectroscopy shows that under the reduction potential,the metal oxide is reduced,and the generated Cu_(2)O can be used as a new active site for the reaction to promote the electrocatalytic conversion of NO_(3)^(-)to NH_(3) synthesis.This work provides valuable guidance for the synthesis of value-added chemicals by 5-hydroxymethylfurfural electrocatalytic oxidation coupled with NO_(3)^(-)while efficiently producing NH_(3).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
Presently,ammonia is an ideal candidate for future clean energy.The Haber-Bosch process has been an essential ammonia production process,and it is one of the most important technological advancements since its inventi...Presently,ammonia is an ideal candidate for future clean energy.The Haber-Bosch process has been an essential ammonia production process,and it is one of the most important technological advancements since its invention,sustaining the explosive growth of military munitions industry and fertilizers in the first half of the 20th century.However,the process is facing great challenges:the growing need for ammonia and the demands of environmental protection.High energy consumption and high CO_(2) emissions greatly limit the application of the Haber-Bosch method,and increasing research efforts are devoted to"green"ammonia synthesis.Thermocatalytic,electrocatalytic,and photocatalytic ammonia production under mild conditions and the derived chemical looping and plasma ammonia production methods,have been widely developed.Electrocatalytic and photocatalytic methods,which use low fossil fuels,are naturally being considered as future directions for the development of ammonia production.Although their catalytic efficiency of ammonia generation is not yet sufficient to satisfy the actual demands,considerable progress has been made in terms of regulating structure and morphology of catalyst and improving preparation efficiency.The chemical looping approach of ammonia production differs from the thermocatalytic,electrocatalytic,and photocatalytic methods,and is the method of reusing raw materials.The plasma treatment approach alters the overall ammonia production approach and builds up a new avenue of development in combination with thermal,photocatalytic,and electrocatalytic methods as well.This review discusses several recent effective catalysts for different ammonia production methods and explores mechanisms as well as efficiency of these catalysts for catalytic N2fixation of ammonia.展开更多
Electrochemical nitrate reduction to ammonia(NRA) can realize the green synthesis of ammonia(NH3) at ambient conditions, and also remove nitrate contamination in water. However, the current catalysts for NRA still fac...Electrochemical nitrate reduction to ammonia(NRA) can realize the green synthesis of ammonia(NH3) at ambient conditions, and also remove nitrate contamination in water. However, the current catalysts for NRA still face relatively low NH3yield rate and poor stability. We present here a core-shell heterostructure comprising cobalt oxide anchored on copper oxide nanowire arrays(CuO NWAs@Co_(3)O_(4)) for efficient NRA. The CuO NWAs@Co_(3)O_(4)demonstrates significantly enhanced NRA performance in alkaline media in comparison with plain CuO NWAs and Co_(3)O_(4)flocs. Especially, at-0.23 V vs. RHE, NH_(3) yield rate of the CuO NWAs@Co_(3)O_(4)reaches 1.915 mmol h^(-1)cm^(-2),much higher than those of CuO NWAs(1.472 mmol h^(-1)cm^(-2)), Co_(3)O_(4)flocs(1.222 mmol h^(-1)cm^(-2)) and recent reported Cu-based catalysts.It is proposed that the synergetic effects of the heterostructure combing atom hydrogen adsorption and nitrate reduction lead to the enhanced NRA performance.展开更多
Electrochemical N_(2) reduction reaction(eNRR) over Cu-based catalysts suffers from an intrinsically low activity of Cu for activation of stable N_(2) molecules and the limited supply of N_(2) to the catalyst due to i...Electrochemical N_(2) reduction reaction(eNRR) over Cu-based catalysts suffers from an intrinsically low activity of Cu for activation of stable N_(2) molecules and the limited supply of N_(2) to the catalyst due to its low solubility in aqueous electrolytes.Herein,we propose phosphorus-activated Cu electrocatalysts to generate electron-deficient Cu sites on the catalyst surface to promote the adsorption of N_(2) molecules.The eNRR system is further modified using a gas diffusion electrode(GDE) coated with polytetrafluoroethylene(PTFE) to form an effective three-phase boundary of liquid water-gas N_(2)-solid catalyst to facilitate easy access of N_(2) to the catalytic sites.As a result,the new catalyst in the flow-type cell records a Faradaic efficiency of 13.15% and an NH_(3) production rate of 7.69 μg h^(-1) cm^(-2) at-0.2 V_(RHE),which represent 3.56 and 59.2 times increases from those obtained with a pristine Cu electrode in a typical electrolytic cell.This work represents a successful demonstration of dual modification strategies;catalyst modification and N_(2) supplying system engineering,and the results would provide a useful platform for further developments of electrocatalysts and reaction systems.展开更多
The electrochemical reduction of nitrate to ammonia(ENRA)provides an efficient approach to remove nitrate pollution and achieve ammonia production simultaneously.Herein,inspired by bio-enzyme in denitrifying bacteria,...The electrochemical reduction of nitrate to ammonia(ENRA)provides an efficient approach to remove nitrate pollution and achieve ammonia production simultaneously.Herein,inspired by bio-enzyme in denitrifying bacteria,a carbon-coated nickel phosphide(NiPC)nanosheet derived from metal-organic frameworks(MOFs)is proposed as an efficient catalyst for ENRA.Through electron engineering,controllable Ni^(δ+)in nickel phosphide is achieved by regulating the degree of phosphating,which enhances its activity for the hydrogenation of nitrate.As the result,Niδ+becomes one of dominating factors determining the efficiency of the ENRA reaction in nickel phosphide.The optimal NiPC catalyst exhibits impressive property toward ENRA:NH_(4)^(+)Faraday efficiency of 96.68%,NH4+selectivity of 99.04%,and nitrate conversion rate of 90.43%under low nitrate concentration(200 mg·L^(−1)).This work opens a new avenue for the design of next-generation catalysts through electron engineering for ENRA.展开更多
Electrochemical nitrate reduction reaction(NO_(3)RR)towards ammonia,as an emerging and appealing technology alternative to the energy-intensive Haber-Bosch process and inefficient nitrogen reduction reaction,has recen...Electrochemical nitrate reduction reaction(NO_(3)RR)towards ammonia,as an emerging and appealing technology alternative to the energy-intensive Haber-Bosch process and inefficient nitrogen reduction reaction,has recently aroused wide concern and research.However,the current research of the NO_(3)RR towards ammonia lacks the overall performance comparison of various electrocatalysts.Given this,we here make a comparison of 12 common transition metal oxide catalysts for the NO_(3)RR under a high cathodic current density of 0.25 A·cm^(-2),wherein Co_(3)O_(4) catalyst displays the highest ammonia Faradaic efficiency(85.15%)and moderate activity(ca.-0.25 V vs.reversible hydrogen electrode).Other external factors,such as nitrate concentrations in the electrolyte and applied potential ranges,have also been specifically investigated for the NO_(3)RR.展开更多
Ammonia production is vital in global industries but faces increasing environmental concerns,necessitating a shift towards sustainable methods.This review comprehensively explores diverse hydrogen production approache...Ammonia production is vital in global industries but faces increasing environmental concerns,necessitating a shift towards sustainable methods.This review comprehensively explores diverse hydrogen production approaches and their potential impact on sustainable ammonia synthesis.The primary focus is investigating hydrogen production methods that enhance both efficiency and sustainability in ammonia synthesis,which is crucial for reducing its environmental footprint.Furthermore,the review highlights the pivotal role of catalysts in improving Faradaic efficiency in ammonia synthesis,emphasizing their significance in overall process efficiency.The study identifies innovative technologies that have the potential to revolutionize ammonia production while aligning with global sustainability goals.Through a thorough examination of hydrogen production methods and catalytic advances,this review provides valuable insight into greener and more efficient ammonia production practices.In conclusion,it emphasizes the importance of exploring hydrogen production methods and leveraging catalysts to improve ammonia production sustainability and efficiency.It addresses a critical research gap and paves the way for an environmentally responsible and globally aligned ammonia production industry.展开更多
Nitrate(NO_(3)^(-))is widely found in wastewater,which is harmful to human health and water environmental.Electrochemical reduction can convert NO_(3)^(-)to high value-added ammonia(NH)3)/ammonium(NH_(4)^(+))for pollu...Nitrate(NO_(3)^(-))is widely found in wastewater,which is harmful to human health and water environmental.Electrochemical reduction can convert NO_(3)^(-)to high value-added ammonia(NH)3)/ammonium(NH_(4)^(+))for pollutant removal and resource recovery.Currently,electrochemical nitrate reduction to produce ammonia(ENRA)is mostly focused on the preparation of high-performance catalysts,while ignoring the prerequisite for industrial application as the stable operation and optimal regulation of the process.Therefore,the review focused on wastewater treatment,based on the mechanism of electrochemical nitrate reduction for ammonia production and reactor construction(reactor,power supply system),then summarized the operation control strategies(such as reduction potential,nitrate concentration,inorganic ions,p H)that should be noted for ENRA.Finally,the challenges(system structure,economy)and prospects(ammonia recovery process,construction of large-scale ENRA system,application of real wastewater)of the field as it moves towards commercialization were discussed.It is hoped that this review will facilitate the scaling up of ENRA in the wastewater treatment field.展开更多
The efficient production of ammonia by reducing nitrates at room temperature and ambient pressure is a promising alternative to the Haber-Bosch process and can effectively overcome the attendant water pollution issues...The efficient production of ammonia by reducing nitrates at room temperature and ambient pressure is a promising alternative to the Haber-Bosch process and can effectively overcome the attendant water pollution issues.Herein,a new idea has been realized for rational and selective construction of the sp-carbon-metal-carbon interface,comprised of electronic-donating triple bonds in graphdiyne and electron-withdrawing iron carbides,for a highly efficient nitrate reduction reaction.The as-prepared sp-carbon-metal-carbon interfacial structures greatly increase the charge transfer ability and electrical conductivity of the system.The proposed concept of incomplete charge transfer has demonstrated significantly high selectivity,activity,and stability in catalytic system.The catalyst exhibits high Faradaic efficiency of over>95%and a NH3 yield rate up to 205.5μmolNH_(3) cm^(-2) h^(-1) in dilute nitrate conditions without any contaminant.展开更多
Electrochemical nitrate reduction reaction(NO_(3)−RR)is an ideal route to produce ammonia(NH_(3))under ambient conditions.Although a markedly improved NH3 production rate has been achieved on the NO_(3)−RR compared wi...Electrochemical nitrate reduction reaction(NO_(3)−RR)is an ideal route to produce ammonia(NH_(3))under ambient conditions.Although a markedly improved NH3 production rate has been achieved on the NO_(3)−RR compared with the nitrogen reduction reaction(NRR),the NH_(3) production rate of NO_(3)−RR is still well below the industrial Haber-Bosch route due to the lack of robust electrocatalysts for yielding high current densitieswith concurrently good suppression of hydrogen evolution reaction(HER).Herein,we describe an in situ electrochemical strategy for the synthesis of hollow carbon-coated Cu nanoparticles(NPs)(HSCu@C)with abundant grain boundaries(HSCu-AGB@C)for highly efficient NO_(3)−RR in both alkaline and neutral media.Impressively,in alkaline media,the HSCu-AGB@C can achieve a maximum NH3 Faradaic efficiency of 94.2% with an ultrahigh NH_(3) rate of 487.8 mmol g^(−1) cat h^(−1) at−0.2 V versus a reversible hydrogen electrode,more than 2.4-fold of the rate obtained in the Haber-Bosch.Both theoretic computations and experimental results uncover that the grain boundaries play the key to improve the NO_(3)−RR performance.Herein,the industrial-scale NH_(3) production ratemay open exciting opportunities for the practical electrosynthesis NH_(3) under ambient conditions.展开更多
The green production of ammonia,in an electrochemical flow cell under ambient conditions,is a promising way to replace the energy-intensive Haber-Bosch process.In the operation of this flow cell with an alkaline elect...The green production of ammonia,in an electrochemical flow cell under ambient conditions,is a promising way to replace the energy-intensive Haber-Bosch process.In the operation of this flow cell with an alkaline electrolyte,water is produced at the anode but also required as an essential reactant at the cathode for nitrogen reduction.Hence,water from the anode is expected to diffuse through the membrane to the cathode to compensate for the water needed for nitrogen reduction.Excessive water permeation,however,tends to increase the possibility of water flooding,which would not only create a large barrier for nitrogen delivery and availability,but also lead to severe hydrogen evolution as side reaction,and thus significantly lower the ammonia production rate and Faradaic efficiency.In this work,the water flooding phenomenon in flow cells for ammonia production via electrocatalytic nitrogen reduction is verified via the visualization approach and the electrochemical cell performance.In addition,the effects of the nitrogen flow rate,applied current density,and membrane thickness on the water crossover flux and ammonia production rate are comprehensively studied.The underlying mechanism of water transport through the membrane,including diffusion and electro-osmotic drag,is precisely examined and specified to provide more insight on water flooding behavior in the flow cell.展开更多
Effects of carrier gas composition（N2/air） on NH3 production, energy efficiency regarding NH3 production and byproducts formation from plasma-catalytic decomposition of urea were systematically investigated using an...Effects of carrier gas composition（N2/air） on NH3 production, energy efficiency regarding NH3 production and byproducts formation from plasma-catalytic decomposition of urea were systematically investigated using an Al2 O3-packed dielectric barrier discharge（DBD） reactor at room temperature. Results show that the presence of O2 in the carrier gas accelerates the conversion of urea but leads to less generation of NH3. The final yield of NH3 in the gas phase decreased from 70.5%, 78.7%, 66.6% and 67.2% to 54.1%, 51.7%, 49.6% and 53.4% for applied voltages of 17, 19, 21 and 23 kV, respectively when air was used as the carrier gas instead of N2.From the viewpoint of energy savings, however, air carrier gas is better than N2 due to reduced energy consumption and increased energy efficiency for decomposition of a fixed amount of urea. Carrier gas composition has little influence on the major decomposition pathways of urea under the synergetic effects of plasma and Al2 O3 catalyst to give NH3 and CO2 as the main products. Compared to a small amount of N2 O formed with N2 as the carrier gas, however,more byproducts including N2O and NO2 in the gas phase and NH4 NO3 in solid deposits were produced with air as the carrier gas, probably due to the unproductive consumption of NH3, the possible intermediate HNCO and even urea by the abundant active oxygen species and nitrogen oxides generated in air-DBD plasma.展开更多
Stable and portable ammonia(NH3)is a promising,low-cost,and environment-friendly medium for energy storage.How to achieve the rapid production of NH3 from reducing NO_(x)^(−)in aqueous systems and industrial wastewate...Stable and portable ammonia(NH3)is a promising,low-cost,and environment-friendly medium for energy storage.How to achieve the rapid production of NH3 from reducing NO_(x)^(−)in aqueous systems and industrial wastewater via electrochemical methods remains the main challenge for practical application on a large scale.The corresponding electrocatalysts as the key materials in electrochemical devices suffer from low activity,especially in neutral systems.In this work,we successfully elevated the activity of the bench-mark Ru electrocatalysts to more than 30 times via construction of rectifying contact of Ru metals and noble carbons.We theoretically predicted and then rationally designed a new type of P-O rich carbon with large work functions as“noble”supports to attract a pronounced number of electrons from Ru metals at the rectifying interface.The resulting electron deficiency of Ru metals largely promotes the pre-adsorption and activation of NO_(x)^(−)anions,providing high Faradaic efficiencies(>96%)and record-high turnover frequency values for universal NO_(2)^(−)and NO_(3)^(−)reduction in neutral solution.展开更多
Designing advanced and cost-effective electrocatalytic system for nitric oxide(NO)reduction reaction(NORR)is vital for sustainable NH_(3) production and NO removal,yet it is a challenging task.Herein,it is shown that ...Designing advanced and cost-effective electrocatalytic system for nitric oxide(NO)reduction reaction(NORR)is vital for sustainable NH_(3) production and NO removal,yet it is a challenging task.Herein,it is shown that phosphorus(P)-doped titania(TiO_(2))nanotubes can be adopted as highly efficient catalyst for NORR.The catalyst demonstrates impressive performance in ionic liquid(IL)-based electrolyte with a remarkable high Faradaic efficiency of 89%and NH3 yield rate of 425μg·h^(−1)·mg_(cat).^(−1),being close to the best-reported results.Noteworthy,the obtained performance metrics are significantly larger than those for N_(2) reduction reaction.It also shows good durability with negligible activity decay even after 10 cycles.Theoretical simulations reveal that the introduction of P dopants tunes the electronic structure of Ti active sites,thereby enhancing the NO adsorption and facilitating the desorption of ^(*)NH_(3).Moreover,the utilization of IL further suppresses the competitive hydrogen evolution reaction.This study highlights the advantage of the catalyst−electrolyte engineering strategy for producing NH_(3) at a high efficiency and rate.展开更多
基金National Natural Science Foundation of China (22179065)Tianjin Graduate Research and Innovation Project (2022BKY018)。
文摘Ammonia plays a crucial role in contemporary society,impacting medicine,agriculture,and the chemical industry.The conventional industrial synthesis of NH_(3) through the Haber-Bosch technique,carried out under severe reaction conditions,leads to substantial energy consumption and environmental pollution.It is thus imperative for NH_(3) synthesis methods to be investigated under more favorable conditions.Synthesis of ammonia by electrocatalysis can effectively reduce the environmental damage and other urgent problems,which is a promising solution.Metal-nitrogen series batteries(M-N batteries),such as metal-nitrogen gas batteries,metal-nitrogen oxide batteries and metal-oxynitride batteries have been regarded recently as an exemplar of concurrent NH_(3) synthesis and energy production.Nonetheless,the large-scale application of these batteries is still limited by numerous challenges are currently existing in building high-efficiency M-N batteries,including poor Faradic efficiency and low NH_(3) yield.Therefore,a comprehensive overview of M-N batteries is offered,specifically focusing on advanced strategies for designing highly efficient cathode catalysts in anticipation of future developments.The metal anodes,cathodic electro-reduction reactions,and design principles are encompassed in the discussion,offering detailed insights to enhance understanding.Mechanisms,feasibility analyses,technoeconomic assessments,device combinations,and comparative evaluations are delved into in the review,contributing to a thorough comprehension of diverse systems and their application potential.Perspectives and opportunities for future research directions are also delineated.
基金the support received from the National Natural Science Foundation of China(Grant No.22372012,22261160640,and 22002009)the Natural Science Foundation of Hunan Province(Grant No.2023JJ20037 and 2021JJ40565)the Scientific Research Project of Hunan Provincial Department of Education(Grant No.22B0293)
文摘The electrochemical coupling of biomass oxidation and nitrogen conversion presents a potential strategy for high value-added chemicals and nitrogen cycling.Herein,in this work,CuO/Co_(3)O_(4)with heterogeneous interface is successfully constructed as a bifunctional catalyst for the electrooxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid and the electroreduction of nitrate to ammonia(NH_(3)).The open-circuit potential spontaneous experiment shows that more 5-hydroxymethylfurfural molecules are adsorbed in the Helmholtz layer of the CuO/Co_(3)O_(4)composite,which certifies that the CuO/Co_(3)O_(4)heterostructure is conducive to the kinetic adsorption of 5-hydroxymethylfurfural.In situ electrochemical impedance spectroscopy further shows that CuO/Co_(3)O_(4)has faster reaction kinetics and lower reaction potential in oxygen evolution reaction and 5-hydroxymethylfurfural electrocatalytic oxidation.Moreover,CuO/Co_(3)O_(4)also has a good reduction effect on NO_(3)^(-).The ex-situ Raman spectroscopy shows that under the reduction potential,the metal oxide is reduced,and the generated Cu_(2)O can be used as a new active site for the reaction to promote the electrocatalytic conversion of NO_(3)^(-)to NH_(3) synthesis.This work provides valuable guidance for the synthesis of value-added chemicals by 5-hydroxymethylfurfural electrocatalytic oxidation coupled with NO_(3)^(-)while efficiently producing NH_(3).
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 National Natural Science Foundation of China (22276194)Institute of Energy of Hefei comprehensive National Science Center (21KZZ501 and 21KZS201)+2 种基金the Presidential Foundation of Hefei Institutes of Physical Science, Chinese Academy of Sciences (YZJJZX202019)funded by the Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah, Saudi Arabia under grant (KEP-PhD: 65-2471443)DSR technical and financial support.
文摘Presently,ammonia is an ideal candidate for future clean energy.The Haber-Bosch process has been an essential ammonia production process,and it is one of the most important technological advancements since its invention,sustaining the explosive growth of military munitions industry and fertilizers in the first half of the 20th century.However,the process is facing great challenges:the growing need for ammonia and the demands of environmental protection.High energy consumption and high CO_(2) emissions greatly limit the application of the Haber-Bosch method,and increasing research efforts are devoted to"green"ammonia synthesis.Thermocatalytic,electrocatalytic,and photocatalytic ammonia production under mild conditions and the derived chemical looping and plasma ammonia production methods,have been widely developed.Electrocatalytic and photocatalytic methods,which use low fossil fuels,are naturally being considered as future directions for the development of ammonia production.Although their catalytic efficiency of ammonia generation is not yet sufficient to satisfy the actual demands,considerable progress has been made in terms of regulating structure and morphology of catalyst and improving preparation efficiency.The chemical looping approach of ammonia production differs from the thermocatalytic,electrocatalytic,and photocatalytic methods,and is the method of reusing raw materials.The plasma treatment approach alters the overall ammonia production approach and builds up a new avenue of development in combination with thermal,photocatalytic,and electrocatalytic methods as well.This review discusses several recent effective catalysts for different ammonia production methods and explores mechanisms as well as efficiency of these catalysts for catalytic N2fixation of ammonia.
基金the financial support from National Natural Science Foundation of China (No. 21972102)National Key Research and Development Program of China (2021YFA0910400)+3 种基金Natural Science Foundation of Jiangsu Province (BK20200991)Suzhou Science and Technology Planning Project (SS202016)the USTS starting fund (No.332012104)the Natural Science Foundation of Suzhou University of Science and Technology (No.342134401)。
文摘Electrochemical nitrate reduction to ammonia(NRA) can realize the green synthesis of ammonia(NH3) at ambient conditions, and also remove nitrate contamination in water. However, the current catalysts for NRA still face relatively low NH3yield rate and poor stability. We present here a core-shell heterostructure comprising cobalt oxide anchored on copper oxide nanowire arrays(CuO NWAs@Co_(3)O_(4)) for efficient NRA. The CuO NWAs@Co_(3)O_(4)demonstrates significantly enhanced NRA performance in alkaline media in comparison with plain CuO NWAs and Co_(3)O_(4)flocs. Especially, at-0.23 V vs. RHE, NH_(3) yield rate of the CuO NWAs@Co_(3)O_(4)reaches 1.915 mmol h^(-1)cm^(-2),much higher than those of CuO NWAs(1.472 mmol h^(-1)cm^(-2)), Co_(3)O_(4)flocs(1.222 mmol h^(-1)cm^(-2)) and recent reported Cu-based catalysts.It is proposed that the synergetic effects of the heterostructure combing atom hydrogen adsorption and nitrate reduction lead to the enhanced NRA performance.
基金supported by the Climate Change Response Project (NRF-2019M1A2A2065612)the Brainlink Project (NRF2022H1D3A3A01081140)+3 种基金the NRF-2021R1A4A3027878 and the No. RS-2023-00212273 funded by the Ministry of Science and ICT of Korea via National Research Foundationresearch funds from Hanhwa Solutions Chemicals (1.220029.01)UNIST (1.190013.01)supported by the Institute for Basic Science (IBS-R019-D1)。
文摘Electrochemical N_(2) reduction reaction(eNRR) over Cu-based catalysts suffers from an intrinsically low activity of Cu for activation of stable N_(2) molecules and the limited supply of N_(2) to the catalyst due to its low solubility in aqueous electrolytes.Herein,we propose phosphorus-activated Cu electrocatalysts to generate electron-deficient Cu sites on the catalyst surface to promote the adsorption of N_(2) molecules.The eNRR system is further modified using a gas diffusion electrode(GDE) coated with polytetrafluoroethylene(PTFE) to form an effective three-phase boundary of liquid water-gas N_(2)-solid catalyst to facilitate easy access of N_(2) to the catalytic sites.As a result,the new catalyst in the flow-type cell records a Faradaic efficiency of 13.15% and an NH_(3) production rate of 7.69 μg h^(-1) cm^(-2) at-0.2 V_(RHE),which represent 3.56 and 59.2 times increases from those obtained with a pristine Cu electrode in a typical electrolytic cell.This work represents a successful demonstration of dual modification strategies;catalyst modification and N_(2) supplying system engineering,and the results would provide a useful platform for further developments of electrocatalysts and reaction systems.
基金the National Natural Science Foundation of China(Nos.22078215 and 22002083)Research Project by Shanxi Scholarship Council of China(No.2021-055).
文摘The electrochemical reduction of nitrate to ammonia(ENRA)provides an efficient approach to remove nitrate pollution and achieve ammonia production simultaneously.Herein,inspired by bio-enzyme in denitrifying bacteria,a carbon-coated nickel phosphide(NiPC)nanosheet derived from metal-organic frameworks(MOFs)is proposed as an efficient catalyst for ENRA.Through electron engineering,controllable Ni^(δ+)in nickel phosphide is achieved by regulating the degree of phosphating,which enhances its activity for the hydrogenation of nitrate.As the result,Niδ+becomes one of dominating factors determining the efficiency of the ENRA reaction in nickel phosphide.The optimal NiPC catalyst exhibits impressive property toward ENRA:NH_(4)^(+)Faraday efficiency of 96.68%,NH4+selectivity of 99.04%,and nitrate conversion rate of 90.43%under low nitrate concentration(200 mg·L^(−1)).This work opens a new avenue for the design of next-generation catalysts through electron engineering for ENRA.
基金supported by the Fundamental Research Funds for the Central Universities,China(No.20720210010)the National Natural Science Foundation of China(Nos.22001081,22075236)the Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM,No.HRTP-[2022]-7).
文摘Electrochemical nitrate reduction reaction(NO_(3)RR)towards ammonia,as an emerging and appealing technology alternative to the energy-intensive Haber-Bosch process and inefficient nitrogen reduction reaction,has recently aroused wide concern and research.However,the current research of the NO_(3)RR towards ammonia lacks the overall performance comparison of various electrocatalysts.Given this,we here make a comparison of 12 common transition metal oxide catalysts for the NO_(3)RR under a high cathodic current density of 0.25 A·cm^(-2),wherein Co_(3)O_(4) catalyst displays the highest ammonia Faradaic efficiency(85.15%)and moderate activity(ca.-0.25 V vs.reversible hydrogen electrode).Other external factors,such as nitrate concentrations in the electrolyte and applied potential ranges,have also been specifically investigated for the NO_(3)RR.
文摘Ammonia production is vital in global industries but faces increasing environmental concerns,necessitating a shift towards sustainable methods.This review comprehensively explores diverse hydrogen production approaches and their potential impact on sustainable ammonia synthesis.The primary focus is investigating hydrogen production methods that enhance both efficiency and sustainability in ammonia synthesis,which is crucial for reducing its environmental footprint.Furthermore,the review highlights the pivotal role of catalysts in improving Faradaic efficiency in ammonia synthesis,emphasizing their significance in overall process efficiency.The study identifies innovative technologies that have the potential to revolutionize ammonia production while aligning with global sustainability goals.Through a thorough examination of hydrogen production methods and catalytic advances,this review provides valuable insight into greener and more efficient ammonia production practices.In conclusion,it emphasizes the importance of exploring hydrogen production methods and leveraging catalysts to improve ammonia production sustainability and efficiency.It addresses a critical research gap and paves the way for an environmentally responsible and globally aligned ammonia production industry.
基金supported by the National Natural Science Foundation of China(No.51508366)Natural Science Foundation of Jiangsu Province(No.BK20201450)+1 种基金Jiangsu Qinglan Project,Suzhou Science and Technology Planning Project(No.SS202016)Kunshan Science and Technology Planning Project(No.KSF202108)。
文摘Nitrate(NO_(3)^(-))is widely found in wastewater,which is harmful to human health and water environmental.Electrochemical reduction can convert NO_(3)^(-)to high value-added ammonia(NH)3)/ammonium(NH_(4)^(+))for pollutant removal and resource recovery.Currently,electrochemical nitrate reduction to produce ammonia(ENRA)is mostly focused on the preparation of high-performance catalysts,while ignoring the prerequisite for industrial application as the stable operation and optimal regulation of the process.Therefore,the review focused on wastewater treatment,based on the mechanism of electrochemical nitrate reduction for ammonia production and reactor construction(reactor,power supply system),then summarized the operation control strategies(such as reduction potential,nitrate concentration,inorganic ions,p H)that should be noted for ENRA.Finally,the challenges(system structure,economy)and prospects(ammonia recovery process,construction of large-scale ENRA system,application of real wastewater)of the field as it moves towards commercialization were discussed.It is hoped that this review will facilitate the scaling up of ENRA in the wastewater treatment field.
基金This research was made possible as a result of a generous grant from the National Natural Science Foundation of China(grant nos.21790050,21790051,and 22021002)the National Key Research and Development Project of China(grant no.2018YFA0703501)the Key Program of the Chinese Academy of Sciences(grant no.XDPB13).
文摘The efficient production of ammonia by reducing nitrates at room temperature and ambient pressure is a promising alternative to the Haber-Bosch process and can effectively overcome the attendant water pollution issues.Herein,a new idea has been realized for rational and selective construction of the sp-carbon-metal-carbon interface,comprised of electronic-donating triple bonds in graphdiyne and electron-withdrawing iron carbides,for a highly efficient nitrate reduction reaction.The as-prepared sp-carbon-metal-carbon interfacial structures greatly increase the charge transfer ability and electrical conductivity of the system.The proposed concept of incomplete charge transfer has demonstrated significantly high selectivity,activity,and stability in catalytic system.The catalyst exhibits high Faradaic efficiency of over>95%and a NH3 yield rate up to 205.5μmolNH_(3) cm^(-2) h^(-1) in dilute nitrate conditions without any contaminant.
基金the National Natural Science Foundation(NNSF)of China(nos.21975162 and 51902208)Shenzhen Government’s Plan of Science and Technology(nos.JCYJ20200109105803806 and JCYJ20190808142219049).
文摘Electrochemical nitrate reduction reaction(NO_(3)−RR)is an ideal route to produce ammonia(NH_(3))under ambient conditions.Although a markedly improved NH3 production rate has been achieved on the NO_(3)−RR compared with the nitrogen reduction reaction(NRR),the NH_(3) production rate of NO_(3)−RR is still well below the industrial Haber-Bosch route due to the lack of robust electrocatalysts for yielding high current densitieswith concurrently good suppression of hydrogen evolution reaction(HER).Herein,we describe an in situ electrochemical strategy for the synthesis of hollow carbon-coated Cu nanoparticles(NPs)(HSCu@C)with abundant grain boundaries(HSCu-AGB@C)for highly efficient NO_(3)−RR in both alkaline and neutral media.Impressively,in alkaline media,the HSCu-AGB@C can achieve a maximum NH3 Faradaic efficiency of 94.2% with an ultrahigh NH_(3) rate of 487.8 mmol g^(−1) cat h^(−1) at−0.2 V versus a reversible hydrogen electrode,more than 2.4-fold of the rate obtained in the Haber-Bosch.Both theoretic computations and experimental results uncover that the grain boundaries play the key to improve the NO_(3)−RR performance.Herein,the industrial-scale NH_(3) production ratemay open exciting opportunities for the practical electrosynthesis NH_(3) under ambient conditions.
基金fully supported by a grant from the National Natural Science Foundation of China(Grant No.52022003).
文摘The green production of ammonia,in an electrochemical flow cell under ambient conditions,is a promising way to replace the energy-intensive Haber-Bosch process.In the operation of this flow cell with an alkaline electrolyte,water is produced at the anode but also required as an essential reactant at the cathode for nitrogen reduction.Hence,water from the anode is expected to diffuse through the membrane to the cathode to compensate for the water needed for nitrogen reduction.Excessive water permeation,however,tends to increase the possibility of water flooding,which would not only create a large barrier for nitrogen delivery and availability,but also lead to severe hydrogen evolution as side reaction,and thus significantly lower the ammonia production rate and Faradaic efficiency.In this work,the water flooding phenomenon in flow cells for ammonia production via electrocatalytic nitrogen reduction is verified via the visualization approach and the electrochemical cell performance.In addition,the effects of the nitrogen flow rate,applied current density,and membrane thickness on the water crossover flux and ammonia production rate are comprehensively studied.The underlying mechanism of water transport through the membrane,including diffusion and electro-osmotic drag,is precisely examined and specified to provide more insight on water flooding behavior in the flow cell.
基金supported by the National Natural Science Foundation of China (Nos. 21547004, 51638001)the Beijing Natural Science Foundation (No. 8152011)the Scientific Research Program of Beijing Municipal Education Commission (No. KM201510005009)
文摘Effects of carrier gas composition（N2/air） on NH3 production, energy efficiency regarding NH3 production and byproducts formation from plasma-catalytic decomposition of urea were systematically investigated using an Al2 O3-packed dielectric barrier discharge（DBD） reactor at room temperature. Results show that the presence of O2 in the carrier gas accelerates the conversion of urea but leads to less generation of NH3. The final yield of NH3 in the gas phase decreased from 70.5%, 78.7%, 66.6% and 67.2% to 54.1%, 51.7%, 49.6% and 53.4% for applied voltages of 17, 19, 21 and 23 kV, respectively when air was used as the carrier gas instead of N2.From the viewpoint of energy savings, however, air carrier gas is better than N2 due to reduced energy consumption and increased energy efficiency for decomposition of a fixed amount of urea. Carrier gas composition has little influence on the major decomposition pathways of urea under the synergetic effects of plasma and Al2 O3 catalyst to give NH3 and CO2 as the main products. Compared to a small amount of N2 O formed with N2 as the carrier gas, however,more byproducts including N2O and NO2 in the gas phase and NH4 NO3 in solid deposits were produced with air as the carrier gas, probably due to the unproductive consumption of NH3, the possible intermediate HNCO and even urea by the abundant active oxygen species and nitrogen oxides generated in air-DBD plasma.
基金This work was supported by the National Natural Science Foundation of China(grant nos.21931005,21720102002,and 22071146)Shanghai Science and Technology Committee(grant nos.19JC1412600 and 20520711600),and the SJTU-MPI partner group.
文摘Stable and portable ammonia(NH3)is a promising,low-cost,and environment-friendly medium for energy storage.How to achieve the rapid production of NH3 from reducing NO_(x)^(−)in aqueous systems and industrial wastewater via electrochemical methods remains the main challenge for practical application on a large scale.The corresponding electrocatalysts as the key materials in electrochemical devices suffer from low activity,especially in neutral systems.In this work,we successfully elevated the activity of the bench-mark Ru electrocatalysts to more than 30 times via construction of rectifying contact of Ru metals and noble carbons.We theoretically predicted and then rationally designed a new type of P-O rich carbon with large work functions as“noble”supports to attract a pronounced number of electrons from Ru metals at the rectifying interface.The resulting electron deficiency of Ru metals largely promotes the pre-adsorption and activation of NO_(x)^(−)anions,providing high Faradaic efficiencies(>96%)and record-high turnover frequency values for universal NO_(2)^(−)and NO_(3)^(−)reduction in neutral solution.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.22075211,21601136,and 21905246)the Key Projects of Zhejiang Natural Science Foundation(Grant No.LZ20E010001).
文摘Designing advanced and cost-effective electrocatalytic system for nitric oxide(NO)reduction reaction(NORR)is vital for sustainable NH_(3) production and NO removal,yet it is a challenging task.Herein,it is shown that phosphorus(P)-doped titania(TiO_(2))nanotubes can be adopted as highly efficient catalyst for NORR.The catalyst demonstrates impressive performance in ionic liquid(IL)-based electrolyte with a remarkable high Faradaic efficiency of 89%and NH3 yield rate of 425μg·h^(−1)·mg_(cat).^(−1),being close to the best-reported results.Noteworthy,the obtained performance metrics are significantly larger than those for N_(2) reduction reaction.It also shows good durability with negligible activity decay even after 10 cycles.Theoretical simulations reveal that the introduction of P dopants tunes the electronic structure of Ti active sites,thereby enhancing the NO adsorption and facilitating the desorption of ^(*)NH_(3).Moreover,the utilization of IL further suppresses the competitive hydrogen evolution reaction.This study highlights the advantage of the catalyst−electrolyte engineering strategy for producing NH_(3) at a high efficiency and rate.
