Pt monolayer on Fe(001) as an alternative cathode catalyst: a first principles study

Abstract

AbstractSpin‐polarized density functional theory (DFT)‐based total energy calculations were performed to investigate the electronic structure of Pt monolayer on Fe(001) {PtML/Fe(001)} and its effect on O2 dissociative adsorption. Local density of states (LDOS) at Pt surface shows induced spin polarization on Pt monolayer increasing unoccupied dzz orbital on Pt surface. The potential energy curves (PEC) for the reaction of Pt with O2 show that the system produces a combination of lower activation barrier for O2 dissociation and a weaker O binding than that of clean Pt(001). The modification of Pt surface electronic structure led to a favorable OPt d interaction with promotion of O unpaired electron antiparallel spin alignment with Pt spin as verified by the decrease in O and Pt magnetic moments upon O adsorption. Such results render stabilization and a lowering of energy cost for O2 activation. The weaker O binding, however, may be attributed to the stronger metal–metal interlayer binding in PtML/Fe(001) than in Pt(001), which indicates an increased stability of Pt monolayer on Fe(001) than on its corresponding pure metal slab. Copyright © 2008 John Wiley & Sons, Ltd.