Preparation and performance evaluation of a Nafion-TiO 2 composite membrane for PEMFCs

Abstract

Nafion/TiO 2 composite membranes were studied for the application in proton exchange membrane fuel cell (PEMFC) to be used with the humidified or dry reactant gases of H 2 and O 2. Composite membranes were prepared by carrying out in-situ sol–gel reaction of Ti (OC 4H 9) 4 in Nafion perfluorosulfonic acid films, such as Nafion112, 1135 and 115. The influence of the concentration of Ti (OC 4H 9) 4 isopropyl alcohol solution on the Ti content in the membranes of different thicknesses was investigated. The X-ray diffraction (XRD) analysis demonstrated that TiO 2 in the composite membranes had a structure of anatase with an average particle size of 4.0 nm. The energy dispersive spectra (EDS) analysis indicated a symmetrical distribution of the TiO 2 particles in the modified membranes. The water retention ability and electrochemical performance of Nafion/TiO 2 composite membranes were evaluated using a single PEMFC operated with humidified or dry gas reactants during a long period.