| Autor: |
Nosov VG; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia., Kupryakov AS; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia., Kolesnikov IE; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia., Vidyakina AA; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia., Tumkin II; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia., Kolesnik SS; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia., Ryazantsev MN; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia.; Nanotechnology Research and Education Centre RAS, Saint Petersburg Academic University, ul. Khlopina 8/3, 194021 St. Petersburg, Russia., Bogachev NA; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia., Skripkin MY; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia., Mereshchenko AS; Saint-Petersburg State University, 7/9 Universitetskaya emb., 199034 St. Petersburg, Russia. |
| Abstrakt: |
A new series of luminescent heterometallic europium(III)-lutetium(III) terephthalate metal-organic frameworks, namely (Eu x Lu 1-x ) 2 bdc 3 ·nH 2 O, was synthesized using a direct reaction in a water solution. At the Eu 3+ concentration of 1-40 at %, the MOFs were formed as a binary mixture of the (Eu x Lu 1-x ) 2 bdc 3 and (Eu x Lu 1-x ) 2 bdc 3 ·4H 2 O crystalline phases, where the Ln 2 bdc 3 ·4H 2 O crystalline phase was enriched by europium(III) ions. At an Eu 3+ concentration of more than 40 at %, only one crystalline phase was formed: (Eu x Lu 1-x ) 2 bdc 3 ·4H 2 O. All MOFs containing Eu 3+ exhibited sensitization of bright Eu 3+ -centered luminescence upon the 280 nm excitation into a 1 ππ* excited state of the terephthalate ion. The fine structure of the emission spectra of Eu 3+ 5 D 0 - 7 F J (J = 0-4) significantly depended on the Eu 3+ concentration. The luminescence quantum yield of Eu 3+ was significantly larger for Eu-Lu terephthalates containing a low concentration of Eu 3+ due to the absence of Eu-Eu energy migration and the presence of the Ln 2 bdc 3 crystalline phase with a significantly smaller nonradiative decay rate compared to the Ln 2 bdc 3 ·4H 2 O. |
