Density Functional Theory Study of the Interaction of Cu, Ag, and Au Atoms with the Regular CeO₂(111) Surface

Abstract

The interaction of Cu, Ag, and Au atoms with the regular terrace sites of the CeO 2 (111) surface has been investigated within the LDA+U and GGA+U density functional theory approaches using different U values and periodic slab surface models. For the interaction of Cu and Ag with this surface the different methods consistently predict the same qualitative description of stable active sites, the same order of stability and the oxidized character of adsorbed Cu and Ag. For the case of Au the description is more method dependent due to the nearly degeneracy between the solutions between cationic and neutral Au, in agreement with a recent study. The present results are indicative of the strength and limitations of the present density functional theory approaches.

Hydrogenation of isoprene over gold supported on CeO2, ZrO2, SiO2 and N–SiO2

“…In order to increase its efficiency, a number of morphological and electronic effects of nanogold catalysts should be understood at first, including perimeter site model [9], extra or lacking electron model [10][11][12][13][14][15] and low coordination sites model [16]. But size distribution and shapes of gold nanoparticles often vary widely, and the particle structure, particularly at the metaloxide interface, is generally not well-defined [17].…”

DFT+U investigation of the catalytic properties of ferruginous clay

“…In each of these cases, apart from in the examination of the bulk and surface structures and properties of mackinawite, it was found that the addition of a Hubbard parameter produced more physically realistic results compared to the computations without this parameter. Although there are many examples of the application of DFT+U for iron-bearing minerals demonstrating the necessity of 5 the inclusion of the Hubbard parameter, (Devey et al 2009;Hsu et al 2010;Kiejna and Pabisiak 2012;Stashans et al 2012) and its importance in the investigation of transition metal oxide surface/interface interactions is well-established, (Nolan et al 2006(Nolan et al , 2008(Nolan et al , 2012Branda et al 2010;Szabová et al 2010) the application to date, of the Hubbard parameter to clay minerals appears to be in its infancy, with our study apparently among the first in this particular field.…”

Cu-doped ceria: Oxygen vacancy formation made easy

“…[12], we discussed results for Cu adsorption on top of the CeO 2 (111) surface (this gave a Cu(+I) ion) and the weaker adsorption above an O vacancy (gave a negative Cu ion) as part of a study of CO and CO 2 interacting with the Cu-CeO 2 system. Branda et al [13] also studied a Cu atom on top of an O-terminated CeO 2 (111) (with a variety of LDA+U and GGA+U flavors) in a study of Cu, Ag and Ag on ceria(111). They found Cu symmetrically surrounded by three O atoms to be the most favorable adsorption site with all the different methods they tried, as we also did in Ref.…”