Expanded polytetrafluoroethylene(e-PTFE)reinforced perfluorosulfonic acid(PFSA)is the predominant proton exchange membrane(PEM)for hydrogen fuel cells.However,the difference in interfacial properties between PFSA and ...Expanded polytetrafluoroethylene(e-PTFE)reinforced perfluorosulfonic acid(PFSA)is the predominant proton exchange membrane(PEM)for hydrogen fuel cells.However,the difference in interfacial properties between PFSA and e-PTFE significantly decreases the proton conduction efficiency and durability of the PEM.In this study,the polyphenolamine treatment method(TA)is employed to effectively enhance the hydrophilicity and interfacial compatibility of e-PTFE,as well as to functionalize the surface of the free radical scavenger ZrO_(2) filler.The surface of the modified e-PTFE and ZrO_(2) is rich in polar phenolic hydroxyl groups and amino groups,which effectively enhance the three-dimensional interface compatibility of the e-PTFE/PFSA reinforced composite membrane(RCM),and improve the proton conductivity by establishing a three-dimensionally-reinforced hydrogen bonding network.The proton conductivity of the RCM is 0.203 S cm^(-1) at 80℃,and the tensile strength is 50.7 MPa.The peak power density of the hydrogen fuel cell based on the composite membrane is 1.46 W cm^(-2) at 80℃ and 50%RH.Moreover,the durability of the composite membrane is considerably improved by the redox properties of the surface functional groups of e-PTFE and the valence-changing properties of ZrO_(2).Following a 72-hour Fenton reaction,the mass loss of the TA@ZrO_(2)/e-PTFE RCM was found to be only 13.5%.The accelerated durability test indicates that the TA@ZrO_(2)/e-PTFE RCM can still provide a current density of 1.3 A cm^(-2) after 5500 dry/wet cycles at 0.55 V.展开更多
基金supported by Chongqing Technology Innovation and Application Development Special Key Project,CSTB2023TIAD-KPX0010 and Chongqing Technology Innovation and Application Development Special Major Project,CSTB2023TIAD-STX0033,and the Science Foundation of National Key Laboratory of Science and Technology on Advanced Composites in Special EnvironmentsNatural Science Foundation of Chongqing,China(Nos.CSTC2021jcyj-msxmX1035,CSTB2022NSCQ-MSX0246,CSTB2022NSCQ-MSX0242,CSTB2022NSCQ-MSX1244,CSTB2022NSCQ-MSX0441,CSTB2022NSCQ-MSX1356,CSTB2022NSCQ-MSX1572,CSTB2022NSCQ-MSX1583,CSTB2022NSCQ-MSX0487,CSTB2022TFII-OFX0034)Fundação para a Ciência e Tecnologia(FCT)for financial support under the framework of Strategic Funding UIDB/04650/2020,UID/FIS/04650/2020,UID/EEA/04436/2020,and under project,10.54499/2022.03931.
文摘Expanded polytetrafluoroethylene(e-PTFE)reinforced perfluorosulfonic acid(PFSA)is the predominant proton exchange membrane(PEM)for hydrogen fuel cells.However,the difference in interfacial properties between PFSA and e-PTFE significantly decreases the proton conduction efficiency and durability of the PEM.In this study,the polyphenolamine treatment method(TA)is employed to effectively enhance the hydrophilicity and interfacial compatibility of e-PTFE,as well as to functionalize the surface of the free radical scavenger ZrO_(2) filler.The surface of the modified e-PTFE and ZrO_(2) is rich in polar phenolic hydroxyl groups and amino groups,which effectively enhance the three-dimensional interface compatibility of the e-PTFE/PFSA reinforced composite membrane(RCM),and improve the proton conductivity by establishing a three-dimensionally-reinforced hydrogen bonding network.The proton conductivity of the RCM is 0.203 S cm^(-1) at 80℃,and the tensile strength is 50.7 MPa.The peak power density of the hydrogen fuel cell based on the composite membrane is 1.46 W cm^(-2) at 80℃ and 50%RH.Moreover,the durability of the composite membrane is considerably improved by the redox properties of the surface functional groups of e-PTFE and the valence-changing properties of ZrO_(2).Following a 72-hour Fenton reaction,the mass loss of the TA@ZrO_(2)/e-PTFE RCM was found to be only 13.5%.The accelerated durability test indicates that the TA@ZrO_(2)/e-PTFE RCM can still provide a current density of 1.3 A cm^(-2) after 5500 dry/wet cycles at 0.55 V.
