Development of Bioanodes Using Salt-Extracted Quaternary Ammonium Bromide/Nafion Membranes to Immobilize Dehydrogenase Enzymes

摘要

Although enzymes are highly efficient catalysts, there have been problems incorporating them into fuel cells. Early enzyme-based fuel cells contained enzymes in solution rather than immobilized on the electrode surface (1 and references within). Enzymes in solutions are only stable for days, whereas immobilized enzymes can be stable for months. One of the main obstacles of enzyme-based biofuel cells has been to immobilize the enzyme in a membrane at the electrode surface that will extend the lifetime of the enzyme and form a mechanically and chemically stable layer, while not forming a capacitive region at the electrode surface. In most H2/O2 fuel cells, the binder that holds the catalyst at the electrode surface is Nafion. Nafion is a perfluorinated ion exchange polymer that has excellent properties as an ion conductor. However, Nafion has not been successful at immobilizing enzymes at the surface of biofuel cell electrodes because Nafion forms an acidic membrane that decreases the lifetime and activity of the enzyme.