Pulling electricity out of air may be a feasible option in the future according to researchers at Oxford University. Fraser Armstrong, Ph.D. and his research team have managed to develop a revolutionary bio fuel cell which promises clean and renewable energy.

The bio fuel cell contains two electrodes that are covered with oxygen-sensitive FeFe hydrogenase enzymes. The enzymes are attached to the electrodes using strong covalent and non-covalent linkages to allow for fast electron transfers. The electrodes and enzymes are then placed within a container of air which has a 3% mixture of hydrogen.

Current testing shows that the prototype fuel cell is capable of powering small electronic devices such as a wristwatch.

"We are at the tip of a large iceberg, with important consequences for the future, but there is still much to do before this generation of enzyme-based fuel cells becomes commercially viable," said Armstrong. "The idea of electricity from hydrogen in air, using an oxygen-tolerant hydrogenase is new, although other scientists have been investigating enzymes as electrocatalysts for years. Most hydrogenases have fragile active sites that are destroyed by even traces of oxygen, but oxygen tolerant hydrogenases have evolved to resist attack."

Armstrong notes that typical hydrogen fuel cells require expensive metals like platinum ($1,000 USD per ounce) to serve as a catalyst for electricity production. Hydrogenases also have roughly the same productivity rate as platinum-based catalysts and do not require complex fuel-separation membranes to operate.