The near-infrared optical properties and Judd–Ofelt analysis of a Dy(III) complex

We have synthesized a trivalent dysprosium ion (Dy3+) complex Dy(PM)3(TP)2 [where PM=1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone and TP=triphenyl phosphine oxide]. Besides visible emission peaked at 480, 572 and 655 nm, near-infrared emission with sharp emission bands range from 800 nm to 1700 nm were detected from this complex. The Judd–Ofelt theory was introduced to calculate the radiative transition rate and the radiative decay time for the 4F9/2→6LJ′ transitions of Dy3+ ion in this complex. The calculated radiative lifetime of the 4F9/2 excited state was 410 μs, compared with the measured luminescent lifetime 17.6 μs, we obtained the radiative quantum efficiency of the 4F9/2 excited state of 4.3% from this Dy (III) complex.