Efficient near-infrared (NIR) luminescent PMMA-supported hybrid materials doped with tris-β-diketonate Ln3+ complex (Ln = Nd or Yb)

Abstract

Abstract Based on the self-assembly of a trifluorinated and acylpyrazole-modified β-diketonate ligand HL ((Z)-3-methyl-1-phenyl-4-(2,2,2-trifluoro-1-hydroxyethylidene)-1 H -pyrazol-5(4H)-one), LnCl3·6H2O (Ln = La, Nd, Yb, Er, Gd, Eu or Tb) and 2,2′-bpy (2,2′-bipyridine), seven tris-β-diketonate complexes [Ln(L)3(2,2′-bpy)] (Ln = La, 1; Ln = Nd, 2; Ln = Yb, 3; Ln = Er, 4; Ln = Gd, 5; Ln = Eu, 6 or Ln = Tb, 7) were obtained, respectively, where the relatively lower ligands-based 3ππ* energy level results in the good NIR luminescent properties (ФLLn = (0.068–1.12% and ηsens = 54-83%) for complexes 2 and 3. Especially for their series of PMMA-supported hybrid materials [Ln(L)3(2,2′-bpy)]@PMMA, the doping not only causes the improved thermal stability and film-forming property, but also endows more efficient NIR luminescent property even at a doping concentration up to 1:200.