A preparation method for catalyst layers of platinum nanoparticles, as used
in direct methanol fuel cells, based on pulsed electrochemical deposition
within the three-phase boundary regions responsible for electrochemical rea
ctions, was developed. A platinum precursor was brought into a carbon-Nafio
n layer and platinum was deposited in situ on the carbon surface. The size,
size distribution and crystallinity of the deposited catalyst particles we
re determined by means of high-resolution transmission electron microscopy
and X-ray diffraction measurements. The electrochemically active surface ar
ea of the deposited catalyst material was investigated by cyclic voltammetr
y, analysing the Pt-H oxidation peak.