Perfluorinated composite membranes with organic antioxidants for chemically durable fuel cells. (1st March 2019)

• Record Type: Journal Article
• Authors: Shin, Sung-Hee; Kodir, Abdul; Shin, Dongwon; Park, Seok-Hee; Bae, Byungchan
• Is Part Of: Electrochimica acta. Volume 298(2019)
• Page Start: 901
• Page End: 909
• Publication Date: 2019-03-01
• Subjects: Perfluorinated composite membrane -- Organic antioxidant -- Proton exchange membrane fuel cell -- Fenton's test -- Open-circuit voltage-holding test; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2018.12.150
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: A perfluorinated composite membrane incorporating an organic antioxidant was prepared to improve the chemical durability of a polymer electrolyte fuel cell. Bipyridine and benzoquinone (BQ) were added as organic antioxidants, and the oxidative stability of the composite electrolyte membranes containing them was evaluated via accelerated aging tests, i.e., an ex situ Fenton's test and in situ open-circuit voltage (OCV)-holding test. The effects of the antioxidants in the Fenton's test were verified using scanning electron microscopy, fluorine ion detection, Fourier-transform infrared spectroscopy, and tensile strength measurements. Moreover, a commercial membrane, NRE211, and a composite membrane, Nafion-BQ, were incorporated into a membrane electrode assembly (MEA) that then underwent an OCV-holding test for 500 h. The change in the MEA state over time was analyzed using cyclic voltammetry and linear sweep voltammetry. While NRE 211 showed a significant reduction in OCV from 300 h, Nafion-BQ maintained a stable OCV for 500 h. Hence, the organic antioxidants added to the electrolyte membrane effectively improved the oxidative stability of the proton exchange membrane fuel cell without sacrificing the ionic conductivity of the perfluorinated electrolyte membrane. Graphical abstract: Highlights: Organic antioxidants were introduced to perfluorinated polymer membrane. No significant drop of proton conductivity & water uptake by organic antioxidants. Chemical durability tests by ex-situ and in-situ accelerated tests. Organic antioxidants improved the oxidative stability significantly. The best antioxidant, BQ, was verified in the long-term OCV-holding test.