Methods for the Preparation of Organic–Inorganic Nanocomposite Polymer Electrolyte Membranes for Fuel Cells

In the last decade, the organic–inorganic nanocomposite polymer electrolyte membranes (PEM) have gained high technical relevance in a wide range of fuel cells applications. The significance of nanocomposite membranes fabrication is particularly highlighted by the fact that one of the major challenges of this century is to provide well-performing and cost-effective membrane materials for fuel cells applications. Many efforts have been made in the development of advanced membranes with the aim to outperform the most commonly used polymer membranes. With the advances in nanomaterials and polymer chemistry, the innovative nanocomposite membranes with superior properties can be designed by various techniques including blending of nanoparticles in a polymer matrix, doping, or infiltration and precipitation of nanoparticles and precursors, self-assembly of nanoparticles, layer-by-layer fabrication method, and nonequilibrium impregnation reduction. This study presents a brief overview of these techniques and discusses the encountered challenges, the problems to be overcome, the major findings and guidance for future developments.