Nitrate(NO_(3)^(-)),a nitrogen-containing pollutant,is prevalent in aqueous solutions,contributing to a range of environmental and health-related issues.The electrocatalytic reduction of NO_(3)^(-)holds promise as a s...Nitrate(NO_(3)^(-)),a nitrogen-containing pollutant,is prevalent in aqueous solutions,contributing to a range of environmental and health-related issues.The electrocatalytic reduction of NO_(3)^(-)holds promise as a sustainable approach to both eliminating NO_(3)^(-)and generating valuable ammonia(NH_(3)).Nevertheless,the reduction reaction of NO_(3)^(-)(NO_(3)^(-)RR),involving 8-electron transfer process,is intricate,necessitating highly efficient electrocatalysts to facilitate the conversion of NO_(3)^(-)to NH_(3).In this study,Fe-doped Co_(3)O_(4) nanowire strutted three-dimensional(3D)pinewood-derived carbon(Fe-Co_(3)O_(4)/PC)is proposed as a high-efficiency NO_(3)^(-)RR electrocatalyst for NH_(3) production.Operating within 0.1 M NaOH containing NO_(3)^(-),Fe-Co_(3)O_(4)/PC demonstrates exceptional performance,obtain an impressively large NH_(3) yield of 0.55 mmol·h^(-1)·cm^(-2) and an exceptionally high Faradaic efficiency of 96.5%at-0.5 V,superior to its Co_(3)O_(4)/PC counterpart(0.2 mmol·h^(-1)·cm^(-2),73.3%).Furthermore,the study delves into the reaction mechanism of Fe-Co_(3)O_(4) for NO_(3)^(-)RR through theoretical calculations.展开更多
NH_(3)is an essential feedstock for fertilizer synthesis.Industry-scale NH_(3)synthesis mostly relies on the Haber-Bosch method,however,which suffers from massive CO_(2) emission and high energy consumption.Electrocat...NH_(3)is an essential feedstock for fertilizer synthesis.Industry-scale NH_(3)synthesis mostly relies on the Haber-Bosch method,however,which suffers from massive CO_(2) emission and high energy consumption.Electrocatalytic NO_(3)-reduction is an attractive substitute to the Haber-Bosch method for synthesizing NH_(3)under mild conditions.As this reaction will produce a variety of products,it highly desires efficient and selective electrocatalyst for NH_(3)generation.Here,we report in situ grown Fe_(3)O_(4)particle on stainless steel(Fe_(3)O_(4)/SS)as a high-efficiency electrocatalyst for NO_(3)^(-)reduction to NH_(3).In 0.1 M NaOH with 0.1 M NaNO_(3),such Fe_(3)O_(4)/SS reaches a remarkable Faradaic efficiency of 91.5%and a high NH_(3)yield of 10,145μg·h^(-1)·cm^(-2)at-0.5 V vs.reversible hydrogen electrode(RHE).Furthermore,it owns robust structural and electrochemical stability.This work provides useful guidelines to expand the scope of metallic oxide electrocatalysts for NH_(3)synthesis.The catalytic mechanism is uncovered and discussed further by theoretical calculations.展开更多
Electrocatalytic nitrate reduction reaction(NO_(3)−RR)emerges as a highly efficient approach toward ammonia synthesis and degrading NO_(3)−contaminant.In our study,CeO_(2) nanoparticles with oxygen vacancies(VO)decora...Electrocatalytic nitrate reduction reaction(NO_(3)−RR)emerges as a highly efficient approach toward ammonia synthesis and degrading NO_(3)−contaminant.In our study,CeO_(2) nanoparticles with oxygen vacancies(VO)decorated N-doped carbon nanorods on graphite paper(CeO_(2)−x@NC/GP)were demonstrated as a highly efficient NO_(3)−RR electrocatalyst.The CeO_(2)−x@NC/GP catalyst manifests a significant NH_(3 )yield up to 712.75μmol·h^(−1)·cm^(−2) at−0.8 V vs.reversible hydrogen electrode(RHE)and remarkable Faradaic efficiency of 92.93%at−0.5 V vs.RHE under alkaline conditions,with excellent durability.Additionally,an assembled Zn-NO_(3)−battery with CeO_(2)−x@NC/GP as cathode accomplishes a high-power density of 3.44 mW·cm^(−2) and a large NH3 yield of 145.08μmol·h^(−1)·cm^(−2).Density functional theory results further expose the NO_(3)−reduction mechanism on CeO_(2)(111)surface with VO.展开更多
文摘Nitrate(NO_(3)^(-)),a nitrogen-containing pollutant,is prevalent in aqueous solutions,contributing to a range of environmental and health-related issues.The electrocatalytic reduction of NO_(3)^(-)holds promise as a sustainable approach to both eliminating NO_(3)^(-)and generating valuable ammonia(NH_(3)).Nevertheless,the reduction reaction of NO_(3)^(-)(NO_(3)^(-)RR),involving 8-electron transfer process,is intricate,necessitating highly efficient electrocatalysts to facilitate the conversion of NO_(3)^(-)to NH_(3).In this study,Fe-doped Co_(3)O_(4) nanowire strutted three-dimensional(3D)pinewood-derived carbon(Fe-Co_(3)O_(4)/PC)is proposed as a high-efficiency NO_(3)^(-)RR electrocatalyst for NH_(3) production.Operating within 0.1 M NaOH containing NO_(3)^(-),Fe-Co_(3)O_(4)/PC demonstrates exceptional performance,obtain an impressively large NH_(3) yield of 0.55 mmol·h^(-1)·cm^(-2) and an exceptionally high Faradaic efficiency of 96.5%at-0.5 V,superior to its Co_(3)O_(4)/PC counterpart(0.2 mmol·h^(-1)·cm^(-2),73.3%).Furthermore,the study delves into the reaction mechanism of Fe-Co_(3)O_(4) for NO_(3)^(-)RR through theoretical calculations.
基金This work was supported by the National Natural Science Foundation of China(No.22072015).
文摘NH_(3)is an essential feedstock for fertilizer synthesis.Industry-scale NH_(3)synthesis mostly relies on the Haber-Bosch method,however,which suffers from massive CO_(2) emission and high energy consumption.Electrocatalytic NO_(3)-reduction is an attractive substitute to the Haber-Bosch method for synthesizing NH_(3)under mild conditions.As this reaction will produce a variety of products,it highly desires efficient and selective electrocatalyst for NH_(3)generation.Here,we report in situ grown Fe_(3)O_(4)particle on stainless steel(Fe_(3)O_(4)/SS)as a high-efficiency electrocatalyst for NO_(3)^(-)reduction to NH_(3).In 0.1 M NaOH with 0.1 M NaNO_(3),such Fe_(3)O_(4)/SS reaches a remarkable Faradaic efficiency of 91.5%and a high NH_(3)yield of 10,145μg·h^(-1)·cm^(-2)at-0.5 V vs.reversible hydrogen electrode(RHE).Furthermore,it owns robust structural and electrochemical stability.This work provides useful guidelines to expand the scope of metallic oxide electrocatalysts for NH_(3)synthesis.The catalytic mechanism is uncovered and discussed further by theoretical calculations.
基金supported by the National Natural Science Foundation of China(No.22072015).
文摘Electrocatalytic nitrate reduction reaction(NO_(3)−RR)emerges as a highly efficient approach toward ammonia synthesis and degrading NO_(3)−contaminant.In our study,CeO_(2) nanoparticles with oxygen vacancies(VO)decorated N-doped carbon nanorods on graphite paper(CeO_(2)−x@NC/GP)were demonstrated as a highly efficient NO_(3)−RR electrocatalyst.The CeO_(2)−x@NC/GP catalyst manifests a significant NH_(3 )yield up to 712.75μmol·h^(−1)·cm^(−2) at−0.8 V vs.reversible hydrogen electrode(RHE)and remarkable Faradaic efficiency of 92.93%at−0.5 V vs.RHE under alkaline conditions,with excellent durability.Additionally,an assembled Zn-NO_(3)−battery with CeO_(2)−x@NC/GP as cathode accomplishes a high-power density of 3.44 mW·cm^(−2) and a large NH3 yield of 145.08μmol·h^(−1)·cm^(−2).Density functional theory results further expose the NO_(3)−reduction mechanism on CeO_(2)(111)surface with VO.
