Effects of Temperature and Relative Humidity on Oxygen Permeation in Nafion® and Sulfonated Poly(Arylene Ether Sulfone)

Oxygen permeation in Nafion®117 and sulfonated poly(arylene ether sulfone) (BPSH-50) were investigated at different temperatures and relative humidities by a potential step method using a Pt microelectrode. The diffusion coefficient increased, while the solubility decreased with an increased in temperature and relative humidity for both samples. Consequently, the permeability increased with an increased in temperature and relative humidity for both samples. The permeability in BPSH-50 was approximately four times lower than that in Nafion®117, due to a smaller diffusion coefficient and a lower solubility in BPSH-50 than those in Nafion®117. Mass transport of oxygen in these membranes was correlated with microstructural changes of the membranes.