Superior Room‐Temperature Anhydrous Proton Conduction in 3D Porous Benzimidazole Membranes Enabled by Strong Acid Confinement
Abstract
Abstract Phosphoric acid‐doped polybenzimidazole (PA‐PBI) is a leading anhydrous proton exchange membrane (APEM) material for non‐aqueous electrochemical technologies. However, its flexible linear backbone results in poorly defined and acid‐sensitive proton conduction pathways, compromising durability and limiting the use of stronger acids for conductivity enhancement. To overcome these limitations, we designed and synthesized a novel self‐standing, 3D benzimidazole‐functionalized covalent triazine framework membrane (OBI‐CTFM) via a sol–gel approach. This membrane exhibits exceptional mechanical strength, strong acid resistance, and an intrinsic microporous structure with alkaline imidazole groups that enable effective acid uptake and confinement. Remarkably, the methanesulfonic acid‐treated membrane (MSA@OBI‐CTFM) achieved a record‐high anhydrous proton conductivity (>10 −2 S cm −1 ) near room temperature, surpassing most reported anhydrous proton conductors. As an APEM in proton batteries, this membrane enabled remarkable cycling stability (∼7000 cycles) and high specific capacity. Our work demonstrates the critical role of 3D porous structures in APEMs and paves the way for advanced PBI membranes in electrochemical applications.
Article Details
Authors (9)
Jin Zhang
Nianyu Zhao
State Key Laboratory of Materials‐Oriented Chemical Engineering and College of Chemistry and Molecular Engineering Nanjing Tech University Nanjing 211816 P. R. China
Qian Liu
Siyao Li
State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, No.130 Meilong Road, Shanghai, 200237, P. R. China
Linzhou Zhuang
State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, No.130 Meilong Road, Shanghai, 200237, P. R. China
Qiao Qiao
Department of Chemistry
Dongsheng Shao
School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
Xiao‐Ming Ren
State Key Laboratory of Materials‐Oriented Chemical Engineering and School of Chemistry and Molecular Engineering Nanjing Tech University Nanjing China
Zhi Xu
State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, No.130 Meilong Road, Shanghai, 200237, P. R. China