Sustainable Conversion of PET Waste Bottle into Proton Exchange Membranes for Fuel Cells

Abstract

This research introduces a sustainable method to transform poly(ethylene terephthalate) (PET) waste bottles into sulfonated proton exchange membranes for fuel cell (PEMFC) applications, addressing the need for alternatives to fluorinated materials like Nafion. The material was obtained in two steps, by amidation through a nucleophilic substitution of 4,4-diamino-2,2-stilbenedisulfonic acid (DSDA) on bis(2-hydroxyethyl) terephthalate (BHET) derived by treating PET with ethylene glycol. The membrane, prepared from the obtained product using the solution casting technique, was tested in a single fuel cell, achieving a power density of 354 mW/cm2, and compared with commercial Nafion 212 membrane (605.4 mW/cm2). The result demonstrates the potential of membrane delivered from PET as a cost-effective and sustainable solution for PEMFCs, addressing critical environmental challenges. This innovative approach transforms waste PET bottles into advanced technologies, providing a key step forward in circular economy solutions.