Preparation and performance of nanoparticle-reinforced chitosan proton-exchange membranes for fuel-cell applications

In this study, we incorporated commercially available p -toluene sulfonic acid coated boehmite nanofillers (commercially known as OS 1 ) into the chitosan (CS) matrix to fabricate CS–OS 1 nanocomposite membranes with a high proton conductivity for fuel-cell applications. These nanocomposite membranes were characterized by Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction analysis, scanning electron microscopy, and thermogravimetric analysis. Their mechanical properties, water uptake, ion-exchange capacity, and proton conductivity were also determined. The results show that the incorporation of OS 1 to CS chains can inhibit the mobility of CS chains and, hence, enhance the thermal stability and mechanical properties of CS–OS 1 nanocomposite membranes. The composite membrane with 5 wt % OS 1 showed a proton conductivity of 0.032 S/cm; this was almost equal to that of commercially available Nafion 117. We concluded that CS–OS 1 nanocomposite membranes have potential for fuel-cell applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 46904.