Flexible biofuel cell with electrodes modified by glucose oxidase-ferrocene and bilirubin oxidase fabricated using microfabrication processes

Abstract

Enzymatic glucose biofuel cells have attracted strong attention because they work under mild operating conditions: at room temperature, neutral pH, and atmospheric pressure. Here, a miniaturized enzymatic biofuel cell generating electricity from glucose and oxygen was fabricated on a polyimide substrate using microfabrication processes. The biofuel cell was equipped with a microchannel 3 mm in width, 12 mm in length, and 200 μm in depth. The 2 × 2 mm2 Pt/Ti anode was covered by porous carbon and treated with glucose oxidase and ferrocene. The 2 × 10 mm2 Pt/Ti cathode was covered by porous carbon and treated with bilirubin oxidase. The biofuel cell exhibited an open circuit voltage of 0.6 V and a maximum power of 1.7 μW at 0.4 V at room temperature when the 200 mM glucose solution was introduced into the cell at 0.0263 ml/s at room temperature. The maximum power corresponded to a power density of 7.2 μW/cm2. The power density obtained here may be practical to drive some simple circuits.