Poly (vinyl alcohol)/Polyquaternium-7 Anion Exchange Membranes for Alkaline Polymer Electrolyte Fuel Cells

Abstract

Anion exchange membrane (AEM) is one of the critical components in Alkaline polymer electrolyte fuel cells. This is due to the crucial function in facilitating the process of hydroxide ion conduction. A series of anion exchange membranes (AEMs) were synthesized using poly (vinyl alcohol) (PVA) as the backbone polymer and polyquaternium-7 as the copolymer that provides a hydroxide conducting group source. Thermal and chemical crosslinking was introduced to reduce the excessive swelling of the membranes. The effect of the PVA/PQ7 mass ratio on AEMs performance was investigated. The FTIR study reveals that the spectra exhibit the primary functional groups of PVA, polyquaternium-7, and chemical crosslinking. According to the SEM image, the PVA/PQ7 membranes have smooth and uniform morphology. Water uptake and swelling degree increased with increasing mass ratio of polyquaternium-7 to PVA. AEMs with a polyquaternium-7 to PVA ratio of 0.5 provide the highest IEC and hydroxide conductivity values of 1.52 mmol/g and 9.26 mS/cm at room temperature, respectively.