Neutral oxygen evolution reaction(OER)is a crucial half-reaction for electrocatalytic chemical production under mild condition,but with limited development due to low activity and poor stability.Herein,a tungsten-dope...Neutral oxygen evolution reaction(OER)is a crucial half-reaction for electrocatalytic chemical production under mild condition,but with limited development due to low activity and poor stability.Herein,a tungsten-doped cobalt molybdate(WDCMO)catalyst was synthesized for efficient and durable OER under neutral electrolyte.It is demonstrated that catalyst reconstruction is suppressed by W doping,which stabilizes the Co-O-Mo point-to-point connection in CoMoO_(4) architecture and stimulates to a lower valence state of active sites over the surface phase.Thereby,the surface structure maintains to avoid compound dissolution caused by over-oxidation during OER.Meanwhile,the WDCMO catalyst promotes charge transfer and optimizes*OH intermediate adsorption,which improves reaction kinetics and intrinsic activity.Consequently,the WDCMO electrode exhibits an overpotential of 302 mV at 10 mA cm^(-2) in neutral electrolyte with an improvement of 182 mV compared with CoMoO4 electrode.Furthermore,W doping significantly improves the electrode stability from 50 h to more than 320 h,with a suppressive potential attenuation from 2.82 to 0.29 mV h^(-1).This work will shed new light on designing rational electrocatalysts for neutral OER.展开更多
The neutral oxygen evolution reaction(OER)in lower OH^(−)-concentration environments suffers from sluggish reaction kinetics,presenting significant challenges for the design of efficient and low-cost electrocatalysts....The neutral oxygen evolution reaction(OER)in lower OH^(−)-concentration environments suffers from sluggish reaction kinetics,presenting significant challenges for the design of efficient and low-cost electrocatalysts.Effectively manipulating the local reaction environment could provide a promising solution.Here,we report a Brønsted base silicate(SiO_(3)^(2−))-modified NiFe(OH)_(x) catalyst.As a proton acceptor,Brønsted base SiO_(3)^(2−)accelerates the cleavage of OH-H bonds at Ni/Fe sites(^(*)H_(2)O→^(*)OH+H^(+)+e^(−)),thereby facilitating ^(*)OH accumulation and enhancing the local ^(*)OH-enriched reaction environment.With these advantages,the optimized NiFe(OH)^(x)-SiO_(3)^(2−)catalyst exhibits a low OER overpotential of 280 mV at 10 mA cm−2,a 150 mV reduction compared to the unmodified NiFe(OH)_(x) catalyst.Furthermore,the membrane electrode assembly electrolyzer using NiFe(OH)_(x)-SiO_(3)^(2−)||Pt/C achieves an energy conversion efficiency of 69.2%and a current density of 1.0 A cm^(−2) at 1.81 V,maintaining stable performance over 240 hours with a negligible degradation.The strategy of Brønsted base SiO_(3)^(2−)modification offers a promising and cost-effective approach for enhancing the efficiency of neutral water electrolysis.展开更多
The neutral oxygen reduction reaction(ORR)has attracted tremendous attention for its broad prospects in next-generation power storage systems.However,the extremely sluggish cathodic reaction process and the limited co...The neutral oxygen reduction reaction(ORR)has attracted tremendous attention for its broad prospects in next-generation power storage systems.However,the extremely sluggish cathodic reaction process and the limited cognition of the reaction mechanism greatly hinder its practical application.Here,we demonstrate a dynamic reconstruction behavior induced by sulfur of the iron-nitrogen(Fe-Nx)species in neutral solution.Our developed FeS_(1)N_(3)-OH configuration effectively optimizes the reaction kinetics by regulating the adsorption energy of oxygen intermediates for central catalytic sites.Consequently,this structure exhibits over 363%enhancement in ORR mass activity compared to the pristine FeN_(4) sites under neutral electrolyte.Moreover,a neutral zinc-air battery assembled with this electrocatalyst reached an ultrahigh peak power density(81.2 mW cm^(−2)),robust stability(more than 100 h)as well as superior tolerance to extreme environments(operating between−20°C and 60°C),representing a critical breakthrough for neutral ORR exploration and application.展开更多
The electrocatalysis of oxygen evolution reaction(OER)plays a key role in clean energy storage and transfer.Nonetheless,the sluggish kinetics and poor durability under acidic and neutral conditions severely hinder pra...The electrocatalysis of oxygen evolution reaction(OER)plays a key role in clean energy storage and transfer.Nonetheless,the sluggish kinetics and poor durability under acidic and neutral conditions severely hinder practical applications such as electrolyzer compatible with the powerful proton exchange membrane and biohybrid fuel production.Here,we report a borondoped ruthenium dioxide electrocatalyst(B-RuO_(2))fabricated by a facile boric acid assisted strategy which demonstrates excellent acidic and neutral OER performances.Density functional theory calculations and advanced characterizations reveal that the boron species form an anomalous B–O covalent bonding with the oxygen atoms of RuO_(2)and expose the fully coordinately bridge ruthenium site(Ru-bri site),which seems like a switch that turns on the inactive Ru-bri site into OER-active,resulting in more exposed active sites,modified electronic structure,and optimized binding energy of intermediates.Thus,the B-RuO_(2)exhibits an ultralow overpotential of 200 mV at 10 mA/cm^(2)and maintains excellent stability compared to commercial RuO_(2)in 0.5 M sulfuric acid.Moreover,the superior performance is as well displayed in neutral electrolyte,surpassing most previously reported catalysts.展开更多
文摘Neutral oxygen evolution reaction(OER)is a crucial half-reaction for electrocatalytic chemical production under mild condition,but with limited development due to low activity and poor stability.Herein,a tungsten-doped cobalt molybdate(WDCMO)catalyst was synthesized for efficient and durable OER under neutral electrolyte.It is demonstrated that catalyst reconstruction is suppressed by W doping,which stabilizes the Co-O-Mo point-to-point connection in CoMoO_(4) architecture and stimulates to a lower valence state of active sites over the surface phase.Thereby,the surface structure maintains to avoid compound dissolution caused by over-oxidation during OER.Meanwhile,the WDCMO catalyst promotes charge transfer and optimizes*OH intermediate adsorption,which improves reaction kinetics and intrinsic activity.Consequently,the WDCMO electrode exhibits an overpotential of 302 mV at 10 mA cm^(-2) in neutral electrolyte with an improvement of 182 mV compared with CoMoO4 electrode.Furthermore,W doping significantly improves the electrode stability from 50 h to more than 320 h,with a suppressive potential attenuation from 2.82 to 0.29 mV h^(-1).This work will shed new light on designing rational electrocatalysts for neutral OER.
基金supported by the National Natural Science Foundation of China(No.52204320 and 52034004)the National Key Research and Development Program of China(2023YFA1507903).
文摘The neutral oxygen evolution reaction(OER)in lower OH^(−)-concentration environments suffers from sluggish reaction kinetics,presenting significant challenges for the design of efficient and low-cost electrocatalysts.Effectively manipulating the local reaction environment could provide a promising solution.Here,we report a Brønsted base silicate(SiO_(3)^(2−))-modified NiFe(OH)_(x) catalyst.As a proton acceptor,Brønsted base SiO_(3)^(2−)accelerates the cleavage of OH-H bonds at Ni/Fe sites(^(*)H_(2)O→^(*)OH+H^(+)+e^(−)),thereby facilitating ^(*)OH accumulation and enhancing the local ^(*)OH-enriched reaction environment.With these advantages,the optimized NiFe(OH)^(x)-SiO_(3)^(2−)catalyst exhibits a low OER overpotential of 280 mV at 10 mA cm−2,a 150 mV reduction compared to the unmodified NiFe(OH)_(x) catalyst.Furthermore,the membrane electrode assembly electrolyzer using NiFe(OH)_(x)-SiO_(3)^(2−)||Pt/C achieves an energy conversion efficiency of 69.2%and a current density of 1.0 A cm^(−2) at 1.81 V,maintaining stable performance over 240 hours with a negligible degradation.The strategy of Brønsted base SiO_(3)^(2−)modification offers a promising and cost-effective approach for enhancing the efficiency of neutral water electrolysis.
基金financially supported by the National Natural Science Foundation of China(No.21925110,91745113,22102170,21890751)the National Program for Support of Top-Notch Young Professionals+3 种基金the Fundamental Research Funds for the Central Universities(No.WK 2060190084)the Youth Innovation Promotion Association of Chinese academy of Sciences(No.Y201877)the Institute of Energy,Hefei Comprehensive National Science Center(Grant No.21KZS213)the support from the Major/Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology。
文摘The neutral oxygen reduction reaction(ORR)has attracted tremendous attention for its broad prospects in next-generation power storage systems.However,the extremely sluggish cathodic reaction process and the limited cognition of the reaction mechanism greatly hinder its practical application.Here,we demonstrate a dynamic reconstruction behavior induced by sulfur of the iron-nitrogen(Fe-Nx)species in neutral solution.Our developed FeS_(1)N_(3)-OH configuration effectively optimizes the reaction kinetics by regulating the adsorption energy of oxygen intermediates for central catalytic sites.Consequently,this structure exhibits over 363%enhancement in ORR mass activity compared to the pristine FeN_(4) sites under neutral electrolyte.Moreover,a neutral zinc-air battery assembled with this electrocatalyst reached an ultrahigh peak power density(81.2 mW cm^(−2)),robust stability(more than 100 h)as well as superior tolerance to extreme environments(operating between−20°C and 60°C),representing a critical breakthrough for neutral ORR exploration and application.
基金the National Key Research and Development Program of China(No.2020YFA0405800)the National Natrual Science Foundation of China(Nos.U1932201,U2032113,and 22075264)+2 种基金CAS Collaborative Innovation Program of Hefei Science Center(No.2020HSC-CIP002)CAS Interdisciplinary Innovation Team,and USTC Research Funds of the Double First-Class Initiative(No.YD2310002003)L.S.also thanks the financial support from State Key Laboratory of Inorganic Synthesis and Preparative Chemistry,College of Chemistry,Jilin University.
文摘The electrocatalysis of oxygen evolution reaction(OER)plays a key role in clean energy storage and transfer.Nonetheless,the sluggish kinetics and poor durability under acidic and neutral conditions severely hinder practical applications such as electrolyzer compatible with the powerful proton exchange membrane and biohybrid fuel production.Here,we report a borondoped ruthenium dioxide electrocatalyst(B-RuO_(2))fabricated by a facile boric acid assisted strategy which demonstrates excellent acidic and neutral OER performances.Density functional theory calculations and advanced characterizations reveal that the boron species form an anomalous B–O covalent bonding with the oxygen atoms of RuO_(2)and expose the fully coordinately bridge ruthenium site(Ru-bri site),which seems like a switch that turns on the inactive Ru-bri site into OER-active,resulting in more exposed active sites,modified electronic structure,and optimized binding energy of intermediates.Thus,the B-RuO_(2)exhibits an ultralow overpotential of 200 mV at 10 mA/cm^(2)and maintains excellent stability compared to commercial RuO_(2)in 0.5 M sulfuric acid.Moreover,the superior performance is as well displayed in neutral electrolyte,surpassing most previously reported catalysts.
