Tetravalent doping of CeO${}_2$: The impact of valence electron character on group IV dopant influence

Abstract

Fluorite CeO${}_2$ doped with group IV elements is studied within the DFT and DFT+U framework. Concentration dependent formation energies are calculated for Ce${}_{1-x}$Z${}_x$O${}_2$ (Z= C, Si, Ge, Sn, Pb, Ti, Zr, Hf) with $0\le x\le 0.25$ and a roughly decreasing trend with ionic radius is observed. The influence of the valence and near valence electronic configuration is discussed, indicating the importance of filled $d$ and $f$ shells near the Fermi level for all properties investigated. A clearly different behavior of group IVa and IVb dopants is observed: the former are more suitable for surface modifications, the latter are more suitable for bulk modifications.\\ \indent For the entire set of group IV dopants, there exists an inverse relation between the change, due to doping, of the bulk modulus and the thermal expansion coefficients. Hirshfeld-I atomic charges show that charge transfer effects due to doping are limited to the nearest neighbor oxygen atoms.

11 pages, 6 tables, 5 figures

References in corpus (4)

• Extending Hirshfeld-I to bulk and periodic materials
• DFT study of La${}_2$Ce${}_2$O${}_7$: disordered fluorite vs pyrochlore structure
• Reply to 'Comment on "Extending Hirshfeld-I to bulk and periodic materials" '
• Tuning of CeO${}_2$ buffer layers for coated superconductors through doping

Cited by in corpus (3)

• A DFT+U study on the contribution of 4f electrons to oxygen vacancy formation and migration in Ln-doped CeO2
• Origin of enhanced visible-light photocatalytic activity of transition metal (Fe, Cr and Co) doped CeO2: Effect of 3d-orbital splitting
• Atomic-scale insights into electro-steric substitutional chemistry of cerium oxide