In Georgia, a glucose-powered biofuel cell that uses electrodes made from cotton fiber could someday help power implantable medical devices such as pacemakers and sensors. The new fuel cell, which provides twice as much power as conventional biofuel cells, could be paired with batteries or supercapacitors to provide a hybrid power source for the medical devices.
Researchers at the Georgia Institute of Technology and Korea University used gold nanoparticles assembled on the cotton to create high-conductivity electrodes that helped improve the fuel cell’s efficiency. That allowed them to address one of the major challenges limiting the performance of biofuel cells – connecting the enzyme used to oxidize glucose with an electrode.
A layer-by-layer assembly technique used to fabricate the gold electrodes – which provide both the electrocatalytic cathode and the conductive substrate for the anode – helped boost the power capacity to as much as 3.7 milliwatts per square centimeter.