Simultaneous Site Adsorption Shift and Efficient CO Oxidation Induced by V and Co in Pt Catalyst

Abstract

A complete solution for CO poisoning of Pt catalysts requires a design that entirely prevents CO adsorption on Pt atoms. Here, we explore the CO adsorption sites and oxidation capability of 3d transition metal doped small magic clusters of Pt4. Among Pt3M, only the Pt3V free-standing cluster entirely eliminates the prospect of Pt poisoning by inverting the adsorption site of CO to V atom. The V d-band center lies closer to the Fermi level than that of Pt atoms, resulting in a larger number of empty d-antibonding states, thereby making V comparatively more reactive toward CO. The inversion of the CO adsorption site is also observed for larger PtnVm clusters and becomes possible for PtnCom clusters for sizes larger than m + n = 12 atoms. Formation and removal of CO2 via the Langmuir–Hinshelwood mechanism occurs with low reaction barriers, exhibiting a high catalytic activity for the Ptn(V/Co)m clusters. A maximum catalytic efficiency is attained for Pt41V14, which at room temperature gives a CO2 turnover fr...