ON THE ROLE OF SURFACE FUNCTIONAL-GROUPS IN PT CARBON INTERACTION

The interaction between platinum crystallites and surface functional g roups of carbon in a homologously prepared series of Pt/C catalysts fo r phosphoric acid fuel cell (PAFC) applications has been studied by X- ray photoelectron spectroscopy (XPS) and potentiometric titration tech niques. It has been found that the platinum surface area depends on th e amount of oxygenated groups on the carbon support. In addition, rela tionships between the platinum electroactive surface area and the acid -base nature of support functionalities have been found. The carbon su pport functional groups have been shown to affect the electronic natur e of the platinum states.