
26 Fuel Cells
either via membrane-associated components, soluble electron shuttles, or
nano-wires. The protons ow through the proton or cation exchange mem-
brane to the cathode.
1.5.8.2 Enzymatic Biofuel Cell
In contrast to microbial biofuel cells, enzymatic biofuel cells utilize the redox
enzymes rather than the whole microorganism as a biocatalyst. The redox
enzyme, which is separated and puried from an organism, participates in
the electron transfer chain that occurs between the substrate and the anode
by oxidizing the fuel or between the substrate and the cathode as shown in
Figure 1.10.
The basic reaction for a functioning between the ...