南京理工大学学报（自然科学版）2026，Vol.50Issue(4)：461-471,11.DOI:10.14177/j.cnki.32-1397n.2026.50.04.009
离子聚合物薄膜的埋藏界面结构及对质子传输的影响
Impact of buried interface structure in ionic polymer membranes on proton transport
摘要
Abstract
Ionomers play a critical role in determining the performance of catalyst layers in polymer electrolyte fuel cells(PEFCs).Although sulfonated aromatic polyether ketone(SPEEK)and perfluorinated sulfonic acid(Nafion)ionomers are commonly employed,their structure-property relationships under operational conditions are not yet fully elucidated.In this work,we conducted a systematic investigation of platinum-supported SPEEK and Nafion ultrathin films(13 nm)using in situ ellipsometry,grazing-incidence wide-angle X-ray scattering(GIWAXS),and electrochemical impedance spectroscopy(EIS)to characterize their morphological features,water uptake behavior,and proton transport properties.In contrast to Nafion,the SPEEK films displayed dense and well-defined crystalline domains at the buried interface,which we attribute to their stronger affinity for the Pt substrate.Quantitative analysis indicated that at 90%RH,the interfacial layer of SPEEK retained a stable thickness of approximately 13.8 Å,whereas Nafion underwent more substantial swelling,expanding to around 18.7 Å.As a result,SPEEK films exhibited lower water uptake and reduced proton conductivity,especially under low-humidity conditions.Furthermore,proton conductivity measurements revealed significant anisotropy in SPEEK,with out-of-plane conductivity values 1-2 orders of magnitude lower than those in the in-plane direction.In comparison,Nafion showed less pronounced directional dependence.We suggest that intramolecular interactions among ether functional groups,combined with specific Pt-oxygen interactions within SPEEK repeat units,underlie the distinct structural attributes observed at the buried interface.关键词
离聚物/薄膜/聚合物电解质燃料电池/同步辐射/掠入射广角X射线散射Key words
ionomer/thin films/polymer electrolyte fuel cells/synchrotron radiation/grazing-incidence wide-angle X-ray scattering分类
能源科技引用本文复制引用
姚璋佳,高啸,卞布衣,太田升,陈雨,易文斌..离子聚合物薄膜的埋藏界面结构及对质子传输的影响[J].南京理工大学学报（自然科学版）,2026,50(4):461-471,11.基金项目
国家自然科学基金青年项目(22302094) （22302094）
江苏省自然科学基金青年项目(BK20251441) （BK20251441）
中央高校基本科研业务费专项资金(30923011017) （30923011017）
