Inorganic Oxide Supported Biomimetic Membranes with Ion Channels for DMFC Application

Methanol crossover of commercial Nafion membranes is a major issue that results in lowering of the efficiency of direct methanol fuel cells (DMFCs). The reason for high crossover in Nafion membrane is the bulk water transport associated with proton transfer. It is thus advantageous to have separate transport of protons and water. Nature has answered this problem in biological membranes which contain selective proton conducting nanochannels. Lynntech proposes to fabricate biomimetic nanocomposite membranes from a nanoporous inorganic matrix and to functionalize them to form proton conducting nanochannels analogous to that in biological membranes. The inorganic matrix provides the structural strength as well as an ordered structure for the proton conducting channels. The functionalized ion channels provide fast proton transfer ability as well as lower the methanol permeability. The target of Phase I is to determine optimal route for the proposed biomimetic membrane fabrication for proton conductivity and methanol crossover for operation with 15M or higher methanol concentration. Mechanical and thermal stability of the promising membranes will also be determined. Preliminary system design for a 1W passive DMFC system with 15M methanol feed will also be made.