Successful preparation of the Ce-Zr-Al oxide thin films and glassy products by a newly developed organic-free modification of the sol-gel technique is reported. The structural composition and some properties of the samples obtained were investigated by TEM, XRD, FTIR, ESR, UV-Vis, PL and XPS. The optical investigation of the obtained films together with ESR data indicate the appearance of the bulk Ce3+-defects (g⊥ = 1.962-1.967, g// = 1.938-1.940, assigned to 4f1 state, with concentration ~2•1018spin/g). The significant PL intensity rising at elevated temperature was related to spontaneous increasing of Ce3+ concentration in sol-gel samples under thermal dehydration. Also, an unexpected formation of intra-band gap states during thermal treatment of xerogels was manifested in UV-Vis spectra. This intra-band-gap states was attributed to the oxygen related defects that contribute to PL signal.
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