Sensitized Luminescence of Lanthanides within the Walls of Polyethylenoxa-Pillared -Zirconium Phosphate

Pillared -zirconim phosphate at low level with a diphosphonic acid resulting from the addition of pentaethyleneglycol to diethyl vinyl phosphonate was prepared and used as a porous matrix to intercalate LnCl3 (Ln = Eu, Tb) and 2,2-bipyridyl (bpy). The uptake levels of both species in mild conditions were 0.35 and 0.10 equivalents per Zr, respectively. Strong interactions between the lanthanide ion and the polyethylenoxa chains were evidenced. Although powder XRD of the composite showed two interlayer distances (1.7 and 2.2 nm) indicating that the material was not homogeneous, excitation luminescence spectra confirmed strong lanthanide bpy-sensitized emission which was more than 50 times higher than that in nonpillared zirconium phosphate