Micromachined microbial fuel cells

This paper presents a micromachined microbial fuel cell as an energy source for microsystems. A microorganism, saccharomyces cerevisiae, is used to catalyse glucose that is the fuel for the cell and electricity is produced by the overall redox reaction. A two-mask, bulk-micromachining process is used to fabricate the fuel cell and the prototype has an electrode area of 0.51 cm/sup 2/. Both proton-exchange membrane and electron mediator are used to assist the operation. The bio-electrical responses of the micromachined microbial fuel cell are characterized with an open-circuit potential measured at an average value of 343 mV. The power density is measured as 0.5 /spl mu/W/cm/sup 3/ under a 10-ohm load.