Energy Transfer and Emission Decay Kinetics in Mixed Microporous Lanthanide Silicates with Unusual Dimensionality

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J. Phys. Chem. C 2008, 112, 260-268

Energy Transfer and Emission Decay Kinetics in Mixed Microporous Lanthanide Silicates with Unusual Dimensionality Rachel C. Evans,*,†,‡,§ Duarte Ananias,‡,| Alastair Douglas,⊥ Peter Douglas,† Luis D. Carlos,*,§ and Joa˜ o Rocha‡ Department of Chemistry, UniVersity of Wales Swansea, Singleton Park, Swansea, SA2 8PP, UK, Department of Chemistry and Department of Physics, UniVersity of AVeiro, CICECO, 3810-193 AVeiro, Portugal, Department of Biochemistry, NMR Centre and Centre of Neurosciences and Cell Biology, UniVersity of Coimbra, 3001-401 Coimbra, Portugal, and AD Technology Consulting Limited, Swansea, SA2 8PP, UK

Downloaded by PORTUGAL CONSORTIA MASTER on July 13, 2009 Published on December 13, 2007 on http://pubs.acs.org | doi: 10.1021/jp0747104

ReceiVed: June 18, 2007; In Final Form: October 3, 2007

We have investigated the energy transfer dynamics in mixed lanthanide open-framework silicates, known as Ln-AV-20 materials, with the stoichiometric formula Na1.08K0.5Ln1.14Si3O8.5‚1.78H2O (Ln ) Gd3+, Tb3+, Eu3+), using steady-state and time-resolved luminescence spectroscopy. Energy transfer between donor and acceptor Ln3+ ions is extremely efficient, even at low molar ratios of the acceptor Ln3+ (