Jie Li, Weiyu Zhang, Wenwen Wang, Jiaqi Ji, Hong Li, Yiming Sun, Keda Li, Tianqi Yang, Weiyi Jin, Yi Tang, Yong-Qing Zhao, Chenliang Gong, Wei Li
{"title":"Phosphonic acid grafted polybenzimidazoles containing pyridine for stable high-temperature proton exchange membrane fuel cells","authors":"Jie Li, Weiyu Zhang, Wenwen Wang, Jiaqi Ji, Hong Li, Yiming Sun, Keda Li, Tianqi Yang, Weiyi Jin, Yi Tang, Yong-Qing Zhao, Chenliang Gong, Wei Li","doi":"10.1039/d4ta05431h","DOIUrl":null,"url":null,"abstract":"The phosphoric acid (PA) leakage problem has been a major constraint in the practical utilization of PA-doped polybenzimidazole for high-temperature proton exchange membranes (HT-PEMs). Increasing the retaining ability of the proton exchange membranes for free PA while decreasing the amount of PA doping seems to be a viable approach to reduce the possibility of PA leakage. In this work, the mild ester exchange reaction was introduced for the first time to prepare phosphonic acid grafted polybenzimidazoles containing pyridine (g-p-X). The phosphonic acid groups act as transport sites for proton conduction, effectively reducing the need for free PA in g-p-X membranes. Meanwhile, the pyridine immobilizes a portion of the PA through strong ionic interactions, and the membranes exhibit a high PA retention capacity. Among them, the g-p-20 membrane reachs 84.6% PA retention after the 120 h test. Thanks to the dual effects of the phosphonic acid groups and pyridine, the g-p-20 membrane shows a proton conductivity of 42 mS cm-1 at 180 oC without humidification. Moreover, with only 175.3 wt% PA doping, its highest single cell power density achieves 951 mW cm-2 (180 oC). Notably, after 120 h of steady operation at 140 oC, the voltage decay rate of the g-p-20 is only 10 μv h-1. This work presents a viable concept for addressing the problem of PA leakage from HT-PEMs in long-term operation.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":null,"pages":null},"PeriodicalIF":10.7000,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Materials Chemistry A","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1039/d4ta05431h","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The phosphoric acid (PA) leakage problem has been a major constraint in the practical utilization of PA-doped polybenzimidazole for high-temperature proton exchange membranes (HT-PEMs). Increasing the retaining ability of the proton exchange membranes for free PA while decreasing the amount of PA doping seems to be a viable approach to reduce the possibility of PA leakage. In this work, the mild ester exchange reaction was introduced for the first time to prepare phosphonic acid grafted polybenzimidazoles containing pyridine (g-p-X). The phosphonic acid groups act as transport sites for proton conduction, effectively reducing the need for free PA in g-p-X membranes. Meanwhile, the pyridine immobilizes a portion of the PA through strong ionic interactions, and the membranes exhibit a high PA retention capacity. Among them, the g-p-20 membrane reachs 84.6% PA retention after the 120 h test. Thanks to the dual effects of the phosphonic acid groups and pyridine, the g-p-20 membrane shows a proton conductivity of 42 mS cm-1 at 180 oC without humidification. Moreover, with only 175.3 wt% PA doping, its highest single cell power density achieves 951 mW cm-2 (180 oC). Notably, after 120 h of steady operation at 140 oC, the voltage decay rate of the g-p-20 is only 10 μv h-1. This work presents a viable concept for addressing the problem of PA leakage from HT-PEMs in long-term operation.
期刊介绍:
The Journal of Materials Chemistry A, B & C covers a wide range of high-quality studies in the field of materials chemistry, with each section focusing on specific applications of the materials studied. Journal of Materials Chemistry A emphasizes applications in energy and sustainability, including topics such as artificial photosynthesis, batteries, and fuel cells. Journal of Materials Chemistry B focuses on applications in biology and medicine, while Journal of Materials Chemistry C covers applications in optical, magnetic, and electronic devices. Example topic areas within the scope of Journal of Materials Chemistry A include catalysis, green/sustainable materials, sensors, and water treatment, among others.