Fuel cell technology has emerged over the past few years as one of the most popular fields of research in our quest to improve efficiencies in modern power generation and storage.
Both power generation and energy storage require an efficient electrode for oxygen reduction. Until now such electrodes have usually been composed of Pt embedded in a porous carbon electrode. Though these electrodes have large current densities perfect for high power applications, a number of intrinsic problems have always remained, such as the cost of the Pt and its contamination in the presence of carbon monoxide.
Now a team of scientists from Australia have developed a Pt free air electrode based on a nanoporous, intrinsically conductive polymer (ICP) multilayer structure, that offers performance similar to that of Pt catalyzed electrodes under similar testing conditions [Winther-Jensen et al., Science (2008) 321, 671].
The scientists coated an electro-active poly(3,4-ethylenedioxythiophene) (PEDOT) layer onto a porous (Goretex) membrane. This unique structure allows critical access of the air stream from one side of the electrode to the high surface are electro active PEDOT layer, which is also in contact with the electrolyte.
Experiments were conducted in different conditions to test the sensitivity of the system, results so far are very promising. The scientists presented results which showed no material degradation or deterioration in performance over 1500 hours. Further studies are currently underway in a bid to provide a platform for a new generation of metal-free electrocatalysts.