Near-infrared luminescent hybrid materials – PMMA doped with a neodymium complex: synthesis, structure and photophysical properties

Abstract

A new β-diketone, 5,6-dimethoxy-2-(2,2,2-trifluoroethyl)-1-indone (5,6-DTFI) and two series of 5,6-DTFI lanthanide complexes, namely, Nd(5,6-DTFI)₃(H₂O)(CH₃OH) (1), Nd(5,6-DTFI)₃(phen) (2), Yb(5,6-DTFI)₃(H₂O)₂ (3) and Yb(5,6-DTFI)₃(phen) (4) (phen = 1,10-phenanthroline), have been isolated. X-ray diffraction analysis reveals that all complexes 1–3 have mononuclear structures. NIR luminescent spectra of complexes 1–4 show strong characteristic emissions of the corresponding Nd³⁺ and Yb³⁺ ions. Upon doping poly(methylmethacrylate) (PMMA) with complex 1 to form a film, the PMMA polymer matrix acts as a co-sensitizer for Nd³⁺ ion and increases the NIR luminescent lifetimes, overall quantum yields and the thermal stability in comparison with the precursor complex 1.