Theoretical studies of Pt–Ti nanoparticles for potential use as PEMFC electrocatalysts

Abstract

A theoretical investigation is presented of alloying platinum with titanium to form binary Pt–Ti nanoalloys as an alternative to the expensive pure platinum catalysts commonly used for Proton Exchange Membrane Fuel Cell cathode electrocatalysts. Density Functional Theory calculations are performed to investigate compositional effects on structural properties as well as Oxygen Reduction Reaction kinetics and poisoning effects. High symmetry A₃₂–B₆clusters are studied to investigate structural properties. From these structures binding energies of hydroxyl and carbon monoxide are studied on a range of sites on the surface of the clusters. Promising results are obtained suggesting that the bimetallic Pt–Ti nanoalloys may exhibit enhanced properties compared to pure platinum catalysts.