The thiol-imidazole functionalized(p-triphenyl-pentafluorobenzaldehyde)polymer(IMPTP)was prepared and quaternized with different side chains to obtain imidazolium-modified Me-IMPTP,He-IMPTP and BIM-IMPTP membranes for...The thiol-imidazole functionalized(p-triphenyl-pentafluorobenzaldehyde)polymer(IMPTP)was prepared and quaternized with different side chains to obtain imidazolium-modified Me-IMPTP,He-IMPTP and BIM-IMPTP membranes for application in high-temperature proton exchange membrane fuel cells(HT-PEMFCs).The presence of the thioether group in the polymers enabled radical scavenging for antioxidant properties,while imidazolium cations interacted strongly with H_(2)PO_(4) to prevent phosphoric acid(PA)leaching.The prepared BIM-IMPTP membrane incorporating bisimidazolium cation string with a long alkyl spacer demonstrated the highest mass retention of 82.93%after being immersed in Fenton's reagent for 24 h.Additionally,the PA-doped BIM-IMPTP membranes exhibited excellent PA retention under high-humidity conditions(80℃/100%RH).The single cell equipped with the BIM-IMPTP/320%PA membrane achieved a maximum power density(PDmax)of 945 mW cm^(-2)at 160℃.Among the four membranes with a similar acid doping content(ADC),the BIM-IMPTP/163%PA membrane with bis-cation pairs in the side chains exhibited a well-developed microphase-separated structure and high proton conductivity(119.0 mS cm^(-1)at 180℃).The single cell assembled with BIM-IMPTP/163%PA membrane maintained a PDmax of 613 mW cm^(-2)at 160℃ and demonstrated long-term operational stability under both 150/400 mA cm^(-2)and 80℃/200 mA cm^(-2)conditions.These results indicate that the introduction of thioether and bis-cation pairs in the structural design of polymers contributes significantly to the long-term stability of HT-PEMs.展开更多
基金supported by the National Natural Science Foundation of China(No.22179047)the Development of Scientific and Technological Project of Jilin Province(20230201139GX).
文摘The thiol-imidazole functionalized(p-triphenyl-pentafluorobenzaldehyde)polymer(IMPTP)was prepared and quaternized with different side chains to obtain imidazolium-modified Me-IMPTP,He-IMPTP and BIM-IMPTP membranes for application in high-temperature proton exchange membrane fuel cells(HT-PEMFCs).The presence of the thioether group in the polymers enabled radical scavenging for antioxidant properties,while imidazolium cations interacted strongly with H_(2)PO_(4) to prevent phosphoric acid(PA)leaching.The prepared BIM-IMPTP membrane incorporating bisimidazolium cation string with a long alkyl spacer demonstrated the highest mass retention of 82.93%after being immersed in Fenton's reagent for 24 h.Additionally,the PA-doped BIM-IMPTP membranes exhibited excellent PA retention under high-humidity conditions(80℃/100%RH).The single cell equipped with the BIM-IMPTP/320%PA membrane achieved a maximum power density(PDmax)of 945 mW cm^(-2)at 160℃.Among the four membranes with a similar acid doping content(ADC),the BIM-IMPTP/163%PA membrane with bis-cation pairs in the side chains exhibited a well-developed microphase-separated structure and high proton conductivity(119.0 mS cm^(-1)at 180℃).The single cell assembled with BIM-IMPTP/163%PA membrane maintained a PDmax of 613 mW cm^(-2)at 160℃ and demonstrated long-term operational stability under both 150/400 mA cm^(-2)and 80℃/200 mA cm^(-2)conditions.These results indicate that the introduction of thioether and bis-cation pairs in the structural design of polymers contributes significantly to the long-term stability of HT-PEMs.