Nano-structured ion-conducting inorganic membranes for fuel cell applications

Abstract

An inorganic proton-conducting membrane and a fuel cell comprising this membrane. The fuel cell comprises a fuel anode, an oxidant cathode, and an inorganic proton-conducting membrane disposed between the anode and the cathode. The membrane is composed of a nano-structured network of proton-exchange inorganic particles. The particles form a sufficiently high density of proton-conducting nanometer-scaled channels with at least one dimension smaller than 100 nanometers so that ionic conductivity of the membrane is no less than 10−6 S/cm (mostly greater than 10−4 S/cm ) at 25° C. or no less than 10−4 S/cm (mostly greater than 10−2 S/cm) at 200° C. This inorganic membrane allows a hydrogen-oxygen fuel cell to operate at a higher temperature without the need (or with a reduced need) to maintain the membrane in a highly hydrated state. A higher operating temperature also implies a fast electro-catalytic reaction of a fuel (e.g., mixture of methanol and water) at the anode permitting a lesser amount of fuel to cross-over the membrane and, hence, a higher fuel utilization efficiency.

Dependencies are inferred from the claim text.