Water Free Operated Phosphoric Acid Doped Radiation‐Grafted Proton Conducting Membranes for High Temperature Polymer Electrolyte Membrane Fuel Cells. Issue 6 (15th September 2014)

• Record Type: Journal Article
• Authors: Sanlı, L. I.; Tas, S.; Yürüm, Y.; Gürsel, S. A.
• Is Part Of: Fuel cells. Volume 14:Issue 6(2014:Dec.)
• Page Start: 914
• Page End: 925
• Publication Date: 2014-09-15
• Subjects: Fuel cells -- Periodicals; 621.312429
• DOI: 10.1002/fuce.201300110
• Languages: English
• ISSNs: 1615-6846

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The present study uses the radiation‐induced grafting method and applies it onto poly(ethylene‐alt‐tetrafluoroethylene) (ETFE) for the synthesis of proton‐exchange membranes by using monomers 4‐vinyl pyridine (4VP), 2‐vinyl pyridine (2VP), <italic>N</italic>‐vinyl‐2‐pyrrolidone (NVP) followed by phosphoric acid doping. Phosphoric acid that provides Grotthuss mechanism in proton mobilization is used to transform the graft copolymers to a high temperature membrane state. Resultant proton‐exchange membranes are verified with their proton conductivity, water uptake, mechanical and thermal properties, and phosphorous distribution as <italic>ex situ</italic> characterization. Our most important finding as a novelty in literature is that ETFE‐<italic>g</italic>‐P4VP phosphoric acid doped proton‐exchange membranes exhibit proton conductivities as 66 mS cm<sup>–1</sup> at 130 °C, 53 mS cm<sup>–1</sup> at 120 °C, 45 mS cm<sup>–1</sup> at 80 °C at RH 100% and 55 mS cm<sup>–1</sup> at 130 °C, 40 mS cm<sup>–1</sup> at 120 °C, 35 mS cm<sup>–1</sup> at 80 °C at dry conditions. Moreover, ETFE‐<italic>g</italic>‐P4VP membranes still conserves the mechanical properties, i.e., tensile strength up to 48 MPa. ETFE‐<italic>g</italic>‐P4VP membranes were tested in PEMFC at 80, 100, and 120 °C and RH <2% and exhibit promising performance as an alternative to commercial Nafion® membranes. The single cell testing performance of ETFE‐<italic>g</italic>‐P4VP membranes is presented for the first time in literature in our study.</p> </abstract>