Synthesis, characterization and photoluminescent properties of Eu(III) complexes with 5‐hydroxy‐2‐hydroxymethyl‐4H‐4‐pyranone and <i>N</i> , <i>N</i> ′‐donor heterocyclic coligands
Shammy Laj Dhania, Archana Chauhan, Ritu Langyan
Abstract
Abstract In present work, five novel europium complexes [Eu(L) 3 ·Phen (2), Eu(L) 3 ·Bipy (3), Eu(L) 3 ·Neo (4), Eu(L) 3 ·Biq (5) and Eu(L) 3 ·Batho (6)] were synthesized, derived from [Eu(L) 3 ·2H 2 O] (1) complex by using ligand (HL) 5‐hydroxy‐2‐(hydroxymethyl)‐4H‐pyran‐4‐one and coligands 1,10‐phenanthroline, bipyridine, neocuproine, 2,2′‐biquinoline and bathophenanthroline. In order to seek excellent photoluminescent properties, coligands were introduced in the complexes to form a rigid conjugated system, thus enhancing luminescence properties of complexes. The synthesized complexes reveal four narrow characteristic emission lines of Eu(III) consistent with 5 D 0 → 7 F J transitions, where J = 0, 1, 2 and 3 at about 580, 595, 614 and 650 nm, respectively. The 5 D 0 → 7 F 2 transition is responsible for strong red luminescence. Color coordinate diagram also indicates that x , y coordinates lie in deep red region. Thermal data are in favour of high thermal stability of synthesized compounds. Owing to their high thermal stability and strong red luminescence, these complexes might be used in fabrication of optoelectronic devices.