XAS STUDY OF CUAL2O4 CERAMIC SYSTEM

XAS technique was used to study changes around Cu atom in the CuAl2O4- Al2O3 system, induced by composition variations. The results showed th at for compositions with 30 and 43% of CuO, the Cu atoms presents the same surrounding of Cu in the CuO oxide (NCu-O=4, RCu-O=1.96 Angstrom) Samples with 20% (doped or undoped) showed significative changes in t he Cu nearest neighbors number (NCu-O=3) and in the mean bond length ( R(Cu-O)similar to 1.93 Angstrom). The qualitative analysis of the edge region showed that for the 20% of CuO sample, some Cu atoms changes f rom Cu+2 to Cu+1. ?his change was more pronounced for the CuO 20% undo ped sample.