Rechargeable Zn-air batteries(ZAB)have drawn extensive attention due to their eco-friendliness and safety.However,the lack of high-performance and low-cost oxygen redox reactions(OER and ORR)catalysts has become one o...Rechargeable Zn-air batteries(ZAB)have drawn extensive attention due to their eco-friendliness and safety.However,the lack of high-performance and low-cost oxygen redox reactions(OER and ORR)catalysts has become one of the main stumbling blocks in their development.Herein,we successfully fabricate a CoFe nanobubble encapsulated in nitrogen-doped carbon nanocage on wood carbon support(CoFe@NC/WC)via pyrolysis of a novel Prussian blue analog(PBA)/spruce precursor.The hierarchical CoFe@NC/WC catalyst exhibits an excellent potential difference of 0.74 V between the OER potential at 10 mA cm^(-2)and half-wave potential of ORR in 0.1 M KOH,comparable to recently reported preeminent electrocatalysts.Further,CoFe@NC/WC shows outstanding electrochemical performance in liquid ZAB,with a peak power density of 138.9 mW cm^(-2)and a specific capacity of 763.5 mAh g^(-1).More importantly,a bacterial cellulose nanofiber reinforced polyacrylic acid(BC-PAA)hydrogel electrolyte shows ultrahigh tensile-breaking stress of 1.58 MPa.In conjunction with the as-prepared CoFe@NC/WC catalyst,BC-PAA-based wearable ZAB displays impressive rechargeability and foldability,and can power portable electronics,such as electronic timer and mobile phone,in bent states.This work provides a new approach toward high-activity and low-cost catalysts for ZAB.展开更多
Constructing an interlayer between perovskite and zinc oxide(ZnO)electron transporting layer to passivate the implacable interfacial defects for upgrading the efficiency and stability of flexible perovskite solar cell...Constructing an interlayer between perovskite and zinc oxide(ZnO)electron transporting layer to passivate the implacable interfacial defects for upgrading the efficiency and stability of flexible perovskite solar cells(f-PSC)is a daunting challenge and remains under explored.Herein,we present a cascade bridge interlayer strategy of zeolitic imidazole framework-8(ZIF-8)at the ZnO/perovskite interface.The ZIF-8 interlayer uplifts thework function,creating a cascade pathway and bridges through nitrogen bonding with Pb^(2+)ions of perovskite,thereby facilitating electron transport and reducing interfacial charge recombination.Consequently,the ZnO surface defects are passivated by alleviating the OH‒species,and thus the device stability is significantly improved.The f-PSC with ZIF-8 interlayer delivers a stable conversion efficiency of 17.10%with minimal hysteresis.By utilizing the piezo-phototronic effect and subjecting the f-PSC to a tensile strain of 1.6%,a stable efficiency of 18.47%was achieved,representing one of the highest reported efficiencies for ZnO nanorods-based f-PSC.Furthermore,the ZnO‒ZIF-8 exhibits high adsorption capacity toward lead and traps the mobile Pb^(2+)ions at the ZnO/perovskite interface,preventing the negative impact of lead leaching on environmental sustainability.展开更多
基金supported by the Innovation and Technology Commission(Grant no.PRP/032/20FX)the RFBR(Grant no.20-03-00772)
文摘Rechargeable Zn-air batteries(ZAB)have drawn extensive attention due to their eco-friendliness and safety.However,the lack of high-performance and low-cost oxygen redox reactions(OER and ORR)catalysts has become one of the main stumbling blocks in their development.Herein,we successfully fabricate a CoFe nanobubble encapsulated in nitrogen-doped carbon nanocage on wood carbon support(CoFe@NC/WC)via pyrolysis of a novel Prussian blue analog(PBA)/spruce precursor.The hierarchical CoFe@NC/WC catalyst exhibits an excellent potential difference of 0.74 V between the OER potential at 10 mA cm^(-2)and half-wave potential of ORR in 0.1 M KOH,comparable to recently reported preeminent electrocatalysts.Further,CoFe@NC/WC shows outstanding electrochemical performance in liquid ZAB,with a peak power density of 138.9 mW cm^(-2)and a specific capacity of 763.5 mAh g^(-1).More importantly,a bacterial cellulose nanofiber reinforced polyacrylic acid(BC-PAA)hydrogel electrolyte shows ultrahigh tensile-breaking stress of 1.58 MPa.In conjunction with the as-prepared CoFe@NC/WC catalyst,BC-PAA-based wearable ZAB displays impressive rechargeability and foldability,and can power portable electronics,such as electronic timer and mobile phone,in bent states.This work provides a new approach toward high-activity and low-cost catalysts for ZAB.
基金supported by City University of Hong Kong(grant no.7020038).
文摘Constructing an interlayer between perovskite and zinc oxide(ZnO)electron transporting layer to passivate the implacable interfacial defects for upgrading the efficiency and stability of flexible perovskite solar cells(f-PSC)is a daunting challenge and remains under explored.Herein,we present a cascade bridge interlayer strategy of zeolitic imidazole framework-8(ZIF-8)at the ZnO/perovskite interface.The ZIF-8 interlayer uplifts thework function,creating a cascade pathway and bridges through nitrogen bonding with Pb^(2+)ions of perovskite,thereby facilitating electron transport and reducing interfacial charge recombination.Consequently,the ZnO surface defects are passivated by alleviating the OH‒species,and thus the device stability is significantly improved.The f-PSC with ZIF-8 interlayer delivers a stable conversion efficiency of 17.10%with minimal hysteresis.By utilizing the piezo-phototronic effect and subjecting the f-PSC to a tensile strain of 1.6%,a stable efficiency of 18.47%was achieved,representing one of the highest reported efficiencies for ZnO nanorods-based f-PSC.Furthermore,the ZnO‒ZIF-8 exhibits high adsorption capacity toward lead and traps the mobile Pb^(2+)ions at the ZnO/perovskite interface,preventing the negative impact of lead leaching on environmental sustainability.
