SYNTHESIS OF ZRF4-BAF2-LNF(3) GLASSES (LN=LA, CE, PR, ND OR EU) BY COMBINED PROCESSES OF SOL-GEL AND FLUORINATION

Amorphous 60Zr0(2) . 30BaO . 10Ln0(1.5) gels (Ln = La, Ce, Pr, Nd or E u) were prepared by sol-gel reactions from alkoxide solutions of Zr, P a and Ln. The dried gels were fluorinated by NF,. The combined process es of sol-gel and fluorination gave 60ZrF(4) . 30BaF(2) . 10LnF(3) gla sses. In the fluorination process the rates of reaction were substanti ally different with the Ln species, becoming slower in the order La, C e, Pr, Nd and Eu. The IR absorption, Eu3+ emission and EU(3+) Mossbaue r spectra of the obtained 60ZrF(4) . 30BaF(2) . 10EuF(3) glass were al most the same as those of a 60ZrF(4) . 30BaF(3) . 10EuF(3) glass prepa red by a conventional melting method. Thermal characteristics of the 6 0ZrF(4) . 30BaF(2) . 10LnF(3) glasses were also examined.