Design and Synthesis of FeCo-N-doped Carbon Nanocages Catalysts for Efficient Oxygen Reduction Reaction

【作者】 李焕新； 付超鹏； 周海晖； 旷亚非；

【机构】 湖南大学化学化工学院； 上海交通大学材料科学与工程学院；

【摘要】 Here,we synthesize a FeCo-N-doped hollow carbon nanocages（FeCo-N-HCN） catalyst for efficient oxygen reduction reaction（ORR） via selective polymerization of pyrrole on porous FeCo oxides（CoFe₂O₄） hollow microspheres.With cobalt incorporation in Fe₃O₄ template via a facile and effective hydrothermal process,CoFe₂O₄ is obtained to serve as sacrifice template,on which the supplemented pyrrole monomers are adsorbed.Then,hydrochloric acid is used to dissolve the CoFe₂O₄ template and thus release Fe³⁺ and Co²⁺ ions.Fe³⁺ can effectively initiate the polymerization of pyrrole monomers while Co²⁺ can not.In this designed strategy,polypyrrole forms on the CoFe₂O₄ template that Fe₂O₃ occupied and pores generate on the position CoO located,resulting in FeCocontaining polypyrrole hollow carbon nanocages（FeCo-PPY-HCN）.Finally,FeCo-PPY-HCN are pyrolyzed to be FeCo-N-doped hollow carbon nanocages（FeCo-N-HCN） under inert atmosphere.For comparison,Fe-N-doped hollow carbon microspheres（Fe-N-HCM） are also prepared by Fe₃O₄ sacrifice templates without cobalt incorporation.The FeCo-N-HCN catalyst displays a superior catalytic activity for oxygen reduction compared with Fe-N-HCM,which can be attributed to the nanocage structure that facilitates exposing more active sites and the synergistic effect of Fe-Co sites that serve as active center for ORR.更多还原

【Abstract】 Here,we synthesize a FeCo-N-doped hollow carbon nanocages（FeCo-N-HCN） catalyst for efficient oxygen reduction reaction（ORR） via selective polymerization of pyrrole on porous FeCo oxides（CoFe₂O₄） hollow microspheres.With cobalt incorporation in Fe₃O₄ template via a facile and effective hydrothermal process,CoFe₂O₄ is obtained to serve as sacrifice template,on which the supplemented pyrrole monomers are adsorbed.Then,hydrochloric acid is used to dissolve the CoFe₂O₄ template and thus release Fe³⁺ and Co²⁺ ions.Fe³⁺ can effectively initiate the polymerization of pyrrole monomers while Co²⁺ can not.In this designed strategy,polypyrrole forms on the CoFe₂O₄ template that Fe₂O₃ occupied and pores generate on the position CoO located,resulting in FeCocontaining polypyrrole hollow carbon nanocages（FeCo-PPY-HCN）.Finally,FeCo-PPY-HCN are pyrolyzed to be FeCo-N-doped hollow carbon nanocages（FeCo-N-HCN） under inert atmosphere.For comparison,Fe-N-doped hollow carbon microspheres（Fe-N-HCM） are also prepared by Fe₃O₄ sacrifice templates without cobalt incorporation.The FeCo-N-HCN catalyst displays a superior catalytic activity for oxygen reduction compared with Fe-N-HCM,which can be attributed to the nanocage structure that facilitates exposing more active sites and the synergistic effect of Fe-Co sites that serve as active center for ORR.更多还原