Imidazolium‐Quaternized Poly(2,6‐Dimethyl‐1,4‐Phenylene Oxide)/Zeolitic Imidazolate Framework‐67 (ImPPOZIF‐67) Composite Membranes for Methanol Fuel Cells

Abstract

A membrane is the powerhouse of a fuel cell, and it is responsible for transport of ions from anode to cathode, thereby producing electricity in the process. In this work, a series of anion exchange membranes based on imidazolium‐quaternized poly(2,6‐dimethyl‐1,4‐phenylene oxide) (ImPPO) functionalized with different wt.% of zeolitic imidazolate framework‐67(ZIF‐67) (1%, 3%, and 5%) were fabricated and evaluated for application in methanol fuel cells. The AEMs had a contact angle in the range of 59.6°–74.6°, water uptake in the range of 29.4%–69.7% at 25°C, 31.2%–79.5% at 60°C, and 51.6%–86.5% at 80°C. Ion exchange capacity (IEC) ranges from 0.66 mmol/g to 1.12 mmol/g, and ion conductivity (IC) from 1.39 mS/cm to 3.11 mS/cm. The best‐performing membrane, ImPPO3%ZIF‐67, shows IEC of 1.12 mmol/g, IC of 3.11 mS/cm, a slight conductivity loss of 35.4% after 120 h in 2 M KOH, and a peak power density of 196.8 mW/cm2.