Abstract
In the present work, a semi-interpenetrating network (semi-IPN) high-temperature proton exchange membrane based on polyethyleneimine (PEI), epoxy resin (ER), and polybenzimidazole (PBI) was prepared and characterized, aiming at their future application in fuel cell devices. The physical properties of the semi-IPN membrane are characterized by thermogravimetric analysis (TGA) and tensile strength test. The results indicate that the as-prepared PEI-ER/PBI semi-IPN membranes possess excellent thermal stability and mechanical strength. After phosphoric acid (PA) doping treatment, the semi-IPN membranes show high proton conductivities. PA doping level and volume swelling ratio as well as proton conductivities of the semi-IPN membranes are found to be positively related to the PEI content. High proton conductivities of 3.9 ∽ 7.8 × 10 − 2 S c m − 1 are achieved at 160°C for these PA-doped PEI-ER/PBI series membranes. H2/O2 fuel cell assembled with PA-doped PEI-ER(1 : 2)/PBI membrane delivered a peak power density of 170 mW cm-2 at 160°C under anhydrous conditions.
Highlights
High-temperature (100-200°C) proton exchange membrane fuel cells (HT-PEMFCs) have been receiving increasing attention on account of their advantages over those operated at lower temperatures, including high tolerance to fuel impurities (e.g., CO and H2S), enhanced activity of the electrocatalysts on both anode and cathode, simplified water, and heat management [1, 2].After nearly 20 years of development, a series of important advances have been made in the research of hightemperature proton exchange membranes
The results indicate that the as-prepared PEI-epoxy resin (ER)/PBI semi-IPN membranes possess excellent thermal stability and mechanical strength
The mechanical properties of membranes were measured with a universal testing machine (New SANS, Shenzhen, China)
Summary
High-temperature (100-200°C) proton exchange membrane fuel cells (HT-PEMFCs) have been receiving increasing attention on account of their advantages over those operated at lower temperatures, including high tolerance to fuel impurities (e.g., CO and H2S), enhanced activity of the electrocatalysts on both anode and cathode, simplified water, and heat management [1, 2]. Tanaka et al [21] prepared PEI-x H3PO4 semi-IPN material by treating linear polyethylenimine (PEI) with H3PO4 of different metering ratios Their proton conductivity at a certain temperature is related to x. When the range of x is extended to 2.5~3.0, the proton conductivity reaches about 10-4 S·cm-1 at 50°C After such amount of phosphate is absorbed, the semi-IPN material will become a paste. Various modification methods have been explored to balance the proton conductivity and mechanical properties of high-temperature proton exchange membranes. When PEI-ER and PBI are blended, an in situ crosslinking between ER and PEI in the presence of PBI can form a semi-interpenetrating network structure, which is expected to improve the mechanical properties and heat resistance of the membrane. The semi-IPN membrane should exhibit excellent proton conductivity at high temperature under anhydrous conditions, meeting the need of the application of HT-PEMFCs
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
