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

Fabrication of titanium dioxide nanomaterial for implantable highly flexible composite bioelectrode for biosensing applications

Implantable and stretchable electrodes have managed to progress the medical field from a medical diagnosis aspect to a patient treatment level. They offer the ability to detect biosignals and conduct electrical current to tissues that aid in muscle stimulation and axon regeneration. Current conventional electrodes are fabricated from stiff and very expensive, precious metals such as platinum. In this work, novel, low cost, and highly flexible electrode materials were fabricated based on titanium dioxide (TiO2) and polymethyl methacrylate (PMMA) supported by a silicone polymer matrix. The electrode materials were characterized by their electrochemical, mechanical, and surface properties. The electrodes possessed high flexibility with Young's modulus of 235 kPa, revealing highly stretchable characteristics. The impedance at 1 kHz was around 114.6 k, and the charge capacity was 1.23 mC/cm2. The fabricated electrodes appeared to have a smooth surface, as seen in the scanning electron microscope micrographs, compared with electrodes in the literature. Long-time stability tests revealed an overall decrease in impedance and an increase in the charge capacity up to 475% of the initial value within three weeks.Sigma-Aldrich Corporation;American University of SharjahScopu