Numerical calculations of space charge layer effects in nanocrystalline ceria. Part II: detailed analysis of the space charge layer properties

Abstract

The numerical approach presented in Part I is used to investigate in detail some important characteristics of space charge layer (SCL) concentration profiles (steepness, extent, charge contributions and total charge), which determine the resulting SCL effects on the ionic and electronic transport. Here, as a case study the conductivity changes in nanocrystalline ceria are discussed over a broad range of dopant concentration (acceptor and donor-doped) as well as space charge potential values. In addition, the effects of a mobile dopant on the SCL charge carrier profiles are addressed. Finally, using the numerical approach the possibilities of adjusting (under realistic conditions) the SCL effects to improve the conduction properties of nanocrystalline CeO₂ are discussed.