Dysprosium(iii) complexes as potential near-white light emitters: a comprehensive study on the influence of coordination environment

Abstract

The coordination of both beta-diketonate and neutral ligands to Dy(III) ions, using a one-pot room temperature synthesis, yielded a series of UV-sensitized luminescent complexes. Specifically, [Dy(BBA)₃(bpy)], [Dy(BBA)₃(phen)], [Dy(BBA)₃(brphen)] and [Dy(BBA)₃(neo)] were obtained, demonstrating efficient UV to Visible conversion. The strategic assembly of 1-(4-bromophenyl)butane-1,3-dione (BBA) and various neutral ligands around the Dy(III) ions resulted in the formation of a protective coordination environment. This environment significantly enhances the luminescence properties, leading to high luminescence intensity and extended emission lifetimes with white emission. A comprehensive analysis of the composition, thermal stability and photophysical properties of these Dy(III) complexes was conducted using FT-IR, NMR, UV-vis, PL and thermal techniques. The structure of the ancillary moieties played an important role in determining the emission characteristics of these Dy(III) coordination complexes, which were found to be thermally stable. The branching ratio, which is a critical parameter for laser design, was also calculated. Additionally, the semiconducting properties, CIE color coordinates and correlated color temperature values were also evaluated.