LUMINESCENCE PROPERTIES OF RARE-EARTH (EU3-ACIDS AND 1,10-PHENANTHROLINE INCORPORATED IN SILICA MATRIX( AND TB3+) COMPLEXES WITH CONJUGATEDCARBOXYLIC)

Binary and ternary complexes of europium and terbium with conjugated c arboxylic acid (nicotinic acid and 3,4-furandicarboxylic acid) and 1,1 0-phenanthroline were introduced into silica gel by the sol-gel method . The luminescence behavior of the complexes in silica gels was studie d compared with the corresponding solid state complexes by means of em ission, excitation spectra and lifetimes. The result indicated that th e rare earth ions (EU3+ and Tb3+) showed fewer emission lines and slig htly lower emission intensities in the silica gel than those in pure r are earth complexes. The lifetimes of rare earth ions (EU3+ and Tb3+) in silica gel doped with rare earth complexes became longer than those in pure rare earth complexes. (C) 1998 Elsevier Science S.A.