Reasonably designing composition and nanostructure to enhance the stability of bifunctional catalysts is highly desired for rechargeable Zn-air batteries(ZABs).Here,porous carbon nanofibers(CNFs)encapsulated CoNiFe al...Reasonably designing composition and nanostructure to enhance the stability of bifunctional catalysts is highly desired for rechargeable Zn-air batteries(ZABs).Here,porous carbon nanofibers(CNFs)encapsulated CoNiFe alloy nanoparticles(NPs)(CoNiFe/CNFs)were synthesized controllably by in-situ growth and cation etching.Electrochemical tests indicated that CoNiFe/CNFs exhibited excellent bifunctional performances in both oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Using CoNiFe/CNFs as bifunctional catalysts,the assembled ZABs presented ultralong durability up to 1050 and 660 h at 5 and 25 mA cm^(-2),respectively.The assembled flexible solid-state ZABs-based polyacrylamide(PAM)hydrogel exhibited a power density of 62.9 mW cm^(-2) and 66 h durability at 2 mA cm^(-2) under ultralow temperature of -40℃.The excellent performance of CoNiFe/CNFs was ascribed to the encapsulation of CNFs by the alloy NPs and the synergy of multi-metals in the alloy NPs,because the encapsulation could suppress alloy spillage and agglomeration and protect the catalytic sites from electrolyte deterioration,thereby boosting the durability of the resulting ZABs.展开更多
基金supported by the National Natural Science Foundation of China(grant no.52103250)the Opening Foundation of State Key Laboratory of Organic-Inorganic Composites,China(grant no.oic-202301001)the Fundamental Research Funds for the Central Universities,China(grant no.buctrc202213).
文摘Reasonably designing composition and nanostructure to enhance the stability of bifunctional catalysts is highly desired for rechargeable Zn-air batteries(ZABs).Here,porous carbon nanofibers(CNFs)encapsulated CoNiFe alloy nanoparticles(NPs)(CoNiFe/CNFs)were synthesized controllably by in-situ growth and cation etching.Electrochemical tests indicated that CoNiFe/CNFs exhibited excellent bifunctional performances in both oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Using CoNiFe/CNFs as bifunctional catalysts,the assembled ZABs presented ultralong durability up to 1050 and 660 h at 5 and 25 mA cm^(-2),respectively.The assembled flexible solid-state ZABs-based polyacrylamide(PAM)hydrogel exhibited a power density of 62.9 mW cm^(-2) and 66 h durability at 2 mA cm^(-2) under ultralow temperature of -40℃.The excellent performance of CoNiFe/CNFs was ascribed to the encapsulation of CNFs by the alloy NPs and the synergy of multi-metals in the alloy NPs,because the encapsulation could suppress alloy spillage and agglomeration and protect the catalytic sites from electrolyte deterioration,thereby boosting the durability of the resulting ZABs.
