EXAFS study of Ce1−Gd O2−/2

Synthesis and characterization of Th1−xLnxO2−x/2 mixed-oxides

“…This structure was stabilized up to x Nd 0.42. As detailed elsewhere [32][33][34][35][74][75][76], the stabilization of the fluorite crystal symmetry despite the incorporation of an aliovalent cation was presumably made possible thanks to the concomitant creation of randomly distributed oxygen vacancies. Weak additional XRD lines located at about 208 and 428 (as pointed out by stars in Fig.…”

Calculation of X-ray absorption near edge structure of CeO2 using a model cluster

“…XANES is suitable technique for the investigation of doped ceria as both the Ce and the corresponding dopant ion can be investigated separately. These advantages have already been demonstrated by X-ray absorption studies including XANES measurement, particularly Ce L III edge, of ceria and ceria with trivalent dopands (Sc 3+ and Gd 3+ ) published by Li et al [6] and that of ceria doped with Gd 2 O 3 by Ohashi et al [7]. Hereby, Ce L III edge XANES has been studied experimentally and showed a characteristic two-peak structure and a shoulder [6,7].…”

“…These advantages have already been demonstrated by X-ray absorption studies including XANES measurement, particularly Ce L III edge, of ceria and ceria with trivalent dopands (Sc 3+ and Gd 3+ ) published by Li et al [6] and that of ceria doped with Gd 2 O 3 by Ohashi et al [7]. Hereby, Ce L III edge XANES has been studied experimentally and showed a characteristic two-peak structure and a shoulder [6,7]. Zhang et al compared XANES with XPS about ceria and investigated the dynamic effect of the oxidation state of cerium [8].…”

Phase Analysis and Oxygen Storage Capacity of Ceria-Lanthana-Based TWC Promoters Prepared by Sol–Gel Routes

“…Beyond the limit of about 0.18 for the La:Ce molar ratio, the decrease of the OSC could be due to an excess density of vacancies, leading to stable vacancy} dopant cation association (24}26) that limits the number of mobile vacancies and therefore the ability of the compound of exchanging oxygen with the environment. Several papers concerning the anionic conductivity in trivalent rare earth (RE)-doped ceria (18,24,27) give experimental evidence that the ionic conductivity actually starts to decrease at about x/(1!x)"0.18 in Ce \V RE V O \V , con"rming that in these systems the mobility of oxygen is crucially dependent on the optimal amount of dopant species. The deviation of the OSC of PdCLAP from the general behavior is not surprising, since the activating action of the precious metal is well documented (2).…”