Judd-Ofelt analysis of warm reddish orange light emanating samarium (III) complexes possessing two band gaps

Abstract

The vermilion color samarium (III) complexes were fabricated with prime ligand and nitrogen donor ancillary ligands adopting one-step grinding method. The chemical composition of these octacoordinated samarium (III) complexes was favoured by elemental analysis and EDAX mapping while the chemical formula of these highly thermally stable complexes was confirmed by IR, UV, 1H NMR and 13C NMR investigations. On monitoring the excitation at 381 nm, the complexes portrayed characteristics emission at 566 nm, 606 nm and 651 nm as a result of electronic transition 4G5/2→6H5/2, 4G5/2→6H7/2 and 4G5/2→6H9/2 respectively, with the most prominent peak at 606 nm (reddish-orange emission). The energy band gap was probed through non-linearly fitting of Tauc's plot to investigate the applications in semiconductors (2 - 4 eV) and solar cells (two band gaps). Using quinine sulfate as a reference, the relative quantum yield of all synthesized complexes (10.10 - 24.33) was computed meticulously. The Judd-Ofelt parameters (13.50–22.53) and most importantly, the quantum efficiency (48.09–86.78) were also ascertained in detail with the help of Judd-Ofelt theory. In addition to that, biological activities were also determined for their applications in the biological field.