可逆的氧还原反应(ORR)和氧析出反应(OER)需要多种类型的活性中心来缓冲质子耦合/解耦的四电子过程.本文通过一种简单环保的熔融NaCl模板法合成了碳包覆FeNi合金、金属-N物种和N缺陷共掺杂的多孔纳米片(FeNi-N/PCN).得到的FeNi-N/PCN作...可逆的氧还原反应(ORR)和氧析出反应(OER)需要多种类型的活性中心来缓冲质子耦合/解耦的四电子过程.本文通过一种简单环保的熔融NaCl模板法合成了碳包覆FeNi合金、金属-N物种和N缺陷共掺杂的多孔纳米片(FeNi-N/PCN).得到的FeNi-N/PCN作为氧电催化剂在碱性(E_(1/2)为0.88 V_(RHE),E_(j=10)为1.57 V_(RHE))和酸性介质(E_(1/2)为0.78 V_(RHE),E_(j=10)为1.76 V_(RHE))中均表现出优异的ORR和OER性能.此外,该FeNi-N/PCN催化剂在锌空气电池中表现出224 m W c m^(-2)的功率密度和691 m A h g^(-1)的比容量,分别是Pt/RuO_(2)组合的1.34和1.20倍.这些优异的性能可以归因于具有多类型活性位点的层状碳纳米片结构,包括碳包覆FeNi合金、N缺陷和金属-N位点(M–N_(x)).展开更多
Pyrolysis-acquired iron and nitrogen codoped carbon(Fe-N-C)has been comprehensively investigated for its promising oxygen reduction reaction(ORR)catalytic performance and structural complexity.The modification of non-...Pyrolysis-acquired iron and nitrogen codoped carbon(Fe-N-C)has been comprehensively investigated for its promising oxygen reduction reaction(ORR)catalytic performance and structural complexity.The modification of non-metal elements with larger atomic radius and the corresponding intrinsic microstructure-property relations are rarely reported.In this study,tellurium(Te)intervened Fe-N-C was prepared by micelles-induced polymerization with Te nanowires as an in-situ intervening agent.The out-plane bonding of Te with Fe induced the increase of both N content and proportion of pyridinic N on the material surface,thus improving the ORR catalytic performance.The assembled Zn-air battery demonstrated a maximum power density of 250 mW/cm^(2)and excellent rate capability under various discharge current densities,which was much better than the Pt/C.Overall,the current work demonstrates a novel Te/Fe-N-C material and reveals an original Te intervened Fe-N-C strategy and N reconfiguration mechanism,which is of great significance for the design of key materials in energy-related fields.展开更多
The controllable construction of non-noble metal based bifunctional catalysts with high activities towards oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of great significance,but remains a challen...The controllable construction of non-noble metal based bifunctional catalysts with high activities towards oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of great significance,but remains a challenge.Herein,we reported an effective method to synthesize cobalt-nitrogen doped mesoporous carbon-based bifunctional oxygen electrocatalyst with controllable phosphorus content(Co-N-P_(X)-MC,X=0.5,1.0,1.5,2.0).The mesoporous carbon substrate endowed the asprepared samples with more exposed active surface(236.50 m^(2)·g^(−1))and the most appropriate doping ratio of phosphorus had been investigated to be 1.5(Co-N-P1.5-MC).For ORR,Co-N-P1.5-MC exhibited excellent catalytic activity with more positive onset potential(1.01 V)and half-wave potential(0.84 V)than the other samples.For OER,Co-N-P1.5-MC also showed a low overpotential of 415 mV.Combining experimental results and density-functional theory(DFT)calculations,the outstanding bifunctional catalytic performance of Co-N-P1.5-MC was due to the synergistic cooperation between the P and N dopants,which could reduce the reaction barriers and was favorable for ORR and OER.Moreover,the Zn-air battery using Co-N-P1.5-MC as the cathode showed remarkable battery performance with high stability(could operate stably for over 160 h at 10 mA·cm^(−2))and maximum power density(119 mW·cm^(−2)),demonstrating its potential for practical applications.This work could provide significant enlightenment towards the design and construction of bifunctional oxygen electrocatalyst for next-generation electrochemical devices.展开更多
The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/el...The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/electron transfer under the gas-solid-liquid triple-phase condition. Herein, an ingenious method through the pyrolysis of creative polyvinylimidazole coordination with Zn/Fe salt precursors is developed to fabricate hierarchically porous Fe-N-doped carbon framework as efficient ORR electrocatalyst. The volatilization of Zn species combined with the nanoscale Kirkendall effect of Fe dopants during the pyrolysis build the hierarchical micro-, meso-, and macroporous nanostructure with a high specific surface area (1,586 m^(2)·g^(−1)), which provide sufficient exposed active sites and multiscale mass/charge transport channels. The optimized electrocatalyst exhibits superior ORR activity and robust stability in both alkaline and acidic electrolytes. The Zn-air battery fabricated by such attractive electrocatalyst as air cathode displays a higher peak power density than that of Pt/C-based Zn-air battery, suggesting the great potential of this electrocatalyst for Zn-air batteries.展开更多
基金supported by the National Natural Science Foundation of China(U19A2017,22272206 and 51976143)the National Key Research and Development Program of China(2018YFA0702001)+4 种基金the Key Research and Development Program of Guangdong Province(2019B090909003)Guangdong Basic and Applied Basic Research Foundation(2020B1515120042)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(XHD2020-002)the Natural Science Foundation of Hunan Province(S2021JJMSXM3153)Zhao C acknowledges Australian Research Council for financial support(FT170100224,LP200100255,and IC200100023)。
文摘可逆的氧还原反应(ORR)和氧析出反应(OER)需要多种类型的活性中心来缓冲质子耦合/解耦的四电子过程.本文通过一种简单环保的熔融NaCl模板法合成了碳包覆FeNi合金、金属-N物种和N缺陷共掺杂的多孔纳米片(FeNi-N/PCN).得到的FeNi-N/PCN作为氧电催化剂在碱性(E_(1/2)为0.88 V_(RHE),E_(j=10)为1.57 V_(RHE))和酸性介质(E_(1/2)为0.78 V_(RHE),E_(j=10)为1.76 V_(RHE))中均表现出优异的ORR和OER性能.此外,该FeNi-N/PCN催化剂在锌空气电池中表现出224 m W c m^(-2)的功率密度和691 m A h g^(-1)的比容量,分别是Pt/RuO_(2)组合的1.34和1.20倍.这些优异的性能可以归因于具有多类型活性位点的层状碳纳米片结构,包括碳包覆FeNi合金、N缺陷和金属-N位点(M–N_(x)).
基金This work was financially supported by the National Natural Science Foundation of China(No.51976143)the National Key Research and Development Program of China(No.2018YFA0702001)+2 种基金the Key Research and Development Program of Guangdong Province(No.2019B090909003)the Guangdong Basic and Applied Basic Research Foundation(No.2020B1515120042)the Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(No.XHD2021-002).The authors would like to thank the Deanship of Scientific Research at Umm Al-Qura University for supporting this work by Grant Code:(No.22UQU4320141DSR13).The authors are thankful to the Dean-ship of Scientific Research at Najran University,Najran,Kingdom of Saudi Arabia for funding this work under the Research Collaboration Funding Program(No.NU/RC/SERC/11/14).
文摘Pyrolysis-acquired iron and nitrogen codoped carbon(Fe-N-C)has been comprehensively investigated for its promising oxygen reduction reaction(ORR)catalytic performance and structural complexity.The modification of non-metal elements with larger atomic radius and the corresponding intrinsic microstructure-property relations are rarely reported.In this study,tellurium(Te)intervened Fe-N-C was prepared by micelles-induced polymerization with Te nanowires as an in-situ intervening agent.The out-plane bonding of Te with Fe induced the increase of both N content and proportion of pyridinic N on the material surface,thus improving the ORR catalytic performance.The assembled Zn-air battery demonstrated a maximum power density of 250 mW/cm^(2)and excellent rate capability under various discharge current densities,which was much better than the Pt/C.Overall,the current work demonstrates a novel Te/Fe-N-C material and reveals an original Te intervened Fe-N-C strategy and N reconfiguration mechanism,which is of great significance for the design of key materials in energy-related fields.
基金supported by the Henan Province Education Department Natural Science Research Item(No.21A480005)the Research Project at School-level of Henan University of Technology(No.2020BS017).
文摘The controllable construction of non-noble metal based bifunctional catalysts with high activities towards oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of great significance,but remains a challenge.Herein,we reported an effective method to synthesize cobalt-nitrogen doped mesoporous carbon-based bifunctional oxygen electrocatalyst with controllable phosphorus content(Co-N-P_(X)-MC,X=0.5,1.0,1.5,2.0).The mesoporous carbon substrate endowed the asprepared samples with more exposed active surface(236.50 m^(2)·g^(−1))and the most appropriate doping ratio of phosphorus had been investigated to be 1.5(Co-N-P1.5-MC).For ORR,Co-N-P1.5-MC exhibited excellent catalytic activity with more positive onset potential(1.01 V)and half-wave potential(0.84 V)than the other samples.For OER,Co-N-P1.5-MC also showed a low overpotential of 415 mV.Combining experimental results and density-functional theory(DFT)calculations,the outstanding bifunctional catalytic performance of Co-N-P1.5-MC was due to the synergistic cooperation between the P and N dopants,which could reduce the reaction barriers and was favorable for ORR and OER.Moreover,the Zn-air battery using Co-N-P1.5-MC as the cathode showed remarkable battery performance with high stability(could operate stably for over 160 h at 10 mA·cm^(−2))and maximum power density(119 mW·cm^(−2)),demonstrating its potential for practical applications.This work could provide significant enlightenment towards the design and construction of bifunctional oxygen electrocatalyst for next-generation electrochemical devices.
基金This work was supported by the National Natural Science Foundation of China(No.51976143)the National Key Research and Development Program of China(No.2018YFA0702001)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(No.XHD2020-002).
文摘The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/electron transfer under the gas-solid-liquid triple-phase condition. Herein, an ingenious method through the pyrolysis of creative polyvinylimidazole coordination with Zn/Fe salt precursors is developed to fabricate hierarchically porous Fe-N-doped carbon framework as efficient ORR electrocatalyst. The volatilization of Zn species combined with the nanoscale Kirkendall effect of Fe dopants during the pyrolysis build the hierarchical micro-, meso-, and macroporous nanostructure with a high specific surface area (1,586 m^(2)·g^(−1)), which provide sufficient exposed active sites and multiscale mass/charge transport channels. The optimized electrocatalyst exhibits superior ORR activity and robust stability in both alkaline and acidic electrolytes. The Zn-air battery fabricated by such attractive electrocatalyst as air cathode displays a higher peak power density than that of Pt/C-based Zn-air battery, suggesting the great potential of this electrocatalyst for Zn-air batteries.
基金supported by the National Natural Science Foundation of China (51976143)the National Key Research and Development Program of China (2018YFA0702001)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory (XHD2020-002)。