Layered yttrium hydroxide compounds based on Eu3+-and/or Tb3+-doped Y-2(OH)(5)NO3 center dot nH(2)O were synthesized in aqueous solutions containing hexamethylenetetramine. Nitrate ions were then exchanged with carboxylate ions such as 4-biphenylacetate (BPA), benzoate, terephthalate, maleate, or oxalate, which were successfully intercalated between yttrium hydroxide layers. While the initial Eu3+- or Tb3+-doped nitrate samples suffered from relatively low photoluminescence (PL) intensity, those intercalated with BPA, benzoate, terephthalate, or oxalate ions showed considerably enhanced PL intensity, accompanying with broad excitation bands at around 220 - 300 nm. This enhancement was explained with the so-called antenna effect of the organic species. In the Eu3+-Tb3+-codoped samples, the antenna effect worked similarly for Eu3+ and Tb3+, thereby resulting in their simultaneous emissions at a single excitation wavelength.

Keywords: Layered compounds; Intercalation; Antenna effect; Photoluminescence