Recent developments in high-temperature proton conducting polymer electrolyte membranes

Progress in the area of proton conducting polymer electrolyte membranes is intimately linked with the development of polymer electrolyte membrane fuel cells, and is today largely driven by the insufficient properties of humidified Nafion(R) membranes at temperatures above 100 degreesC. Recent developments in the field include new ionomers and hybrid membranes containing inorganic nanoparticles to control morphology and enhance water retention, as well as improved systems based on the complexation of basic polymers with oxo-acids. In addition, the molecular design and synthesis of completely new all-polymeric electrolytes that rely entirely on structure diffusion of the protons holds great promise in the long perspective. (C) 2003 Elsevier Science Ltd. All rights reserved.