Systematic Theoretical Study of Alloys of Platinum for Enhanced Methanol Fuel Cell Performance

Abstract

The ability of substitutional atoms in the (111)Pt surface to attract a water molecule and activate the formation of on them is calculated using the ASED‐MO theory. is believed to be the oxidant that removes the CO poison from Pt anode surfaces in organic fuel cells. A total of 42 alloying atoms is treated, Sc through Se from period 4, Y through Te from period 5, and La through Po from period 6. As surface substitutional atoms, no elements to the right of the Pt group are found to attract strongly enough to activate OH dissociation. Some of these elements, including Sn, are known to be active in the electrocatalytic oxidation of but are believed to be atoms or complexes on or near the Pt surface. Of the elements to the left of the Pt group, a number from the first and second transition series attract and activate with comparable or greater effectiveness than Ru, a known activator when present on Pt electrode surfaces. Whether these can be made stable alloy surfaces for organic fuel cell operation is an experimental issue. Past experimental work in the literature suggests promise for some of them.