Size and spatial correlation of defective domains in yttrium-doped CeO2

摘要: The size of dopant-rich nanodomains was assessed in four samples Ce1−μ Y μ O2−μ/2 through systematic pair distribution function (PDF) refinements. Experimental G(r) curves were fitted by different structural models with the aim finding a description which balanced precise structure parameterization and reasonable number parameters. most reliable model single Y2O3-like phase, best accommodated to close relationship between fluorite (CeO2-like) C-type (Y2O3-like) structures. In this model, refined cation coordinate, x(M2), measured relative occurrence chemical environment Ce at any value r. r-value x(M2) vanished, i.e. cell becomes redundant, low-symmetry cell, assumed as domain. Subtle features could be attributed or phase up ~500 A thanks narrow instrumental resolution ID31 beamline (now ID22) ESRF, allows us get high PDF data.