Novel composite Nafion membranes modified with copper phthalocyanine tetrasulfonic acid tetrasodium salt for fuel cell application

Abstract

In this paper, Nafion membrane was firstly modified by copper phthalocyanine tetrasulfonic acid tetrasodium salt (CuTSPc) to prepare the Nafion/CuTSPc-x composite membranes. FTIR, XRD and SEM results revealed the successful incorporation of CuTSPc into Nafion and good compatibility between the two composites. The proton conductivities of the Nafion/CuTSPc-x composite membranes were evidently higher than pure cast Nafion membrane, and increased with CuTSPc contents. Among them, the Nafion/CuTSPc-6% membrane with the highest ion exchange capacity (1.14 mequiv•g−1) exhibited the highest proton conductivity of 0.084 S cm−1 at 30 °C and 0.131 S cm−1 at 80 °C, respectively. When fabricated of a membrane electrode assembly (MEA), the Nafion/CuTSPc-4.5% membrane displayed an initial fuel cell performance with a power density of 43.3 mW cm−2 at room temperature, close to that for pure cast Nafion membrane. Benefiting from the compact structure, high proton conductivity and outstanding stability, the Nafion/CuTSPc-x composite membranes show promising potentials for fuel cell applications. Keywords: Proton exchange membrane, Proton conductivity, Stability, Fuel cell