Sensitized near-infrared luminescence from erbium ion-associated complex with IR140 dye

In this study, the near-infrared luminescence emission of erbium ions is enhanced by 6-folds in intensity with an ion-associated erbium complex consisting of an IR140 dye cation. The energy-transfer process from the IR140 dye cation to the erbium ion has been modeled. Near-infrared luminescence of the erbium ion is sensitized intra-molecularly by the IR140 dye cation effectively, although the residual IR140 dye emission is still observed, indicating an incomplete energy transfer between the IR140 dye cation and the erbium ion. The main path of energy-transfer process is through the T1 → 4I11/2 transition with the operative mechanism to be Förster type.

► An ion-associated erbium complex consisting of an IR140 dye cation. ► The near-infrared luminescence emission of the erbium ion is enhanced by 6-folds. ► The near-infrared luminescence of the erbium ion is sensitized by the IR140 cation. ► The energy-transfer process from the IR140 cation to the erbium ion has been modeled. ► The main path of the Förster type energy-transfer process is through the T1 → 4I11/2.