Researchers in Japan have obtained key evidence concerning failures in proton-exchange membrane (PEM) fuel cells.

Platinum deposition in a polymer electrode membrane

Kazuaki Yasuda and colleagues from the National Institute of Advanced Industrial Science in Osaka used potential cycling and electron microscopy to study dissolved platinum in the membrane of such fuel cells. 

PEM cells convert energy in fuel directly to electrical energy. They are potential power sources for electrically powered vehicles and portable electronic devices.

Degradation of platinum from the cathode of the cell is thought to contribute to failures of these devices. The causes and mechanisms of this degradation are not fully understood.

Yasuda's team found that several factors including the thickness of the membrane and the presence or absence of hydrogen or oxygen affected the distribution of platinum within the fuel cell. 

Niamh O'Connor