Near-infrared (NIR) emitting Nd/Yb(III) complexes sensitized by MLCT states of Ru(II)/Ir(III) metalloligands in the visible light region

Dalton Trans. 2015 Sep 14;44(34):15212-9. doi: 10.1039/c5dt00545k.

Abstract

Four Ru(II)/Ir(III) metalloligands have been designed and synthesized from polypyridine and bibenzimidazole (BiBzIm) organic ligands, which show strong visible light absorption via metal-to-ligand charge transfer (MLCT) transitions. Nd/Yb(III) complexes were further assembled from these Ru(II)/Ir(III) metalloligands, and Ln(III)-centered NIR emissions can be efficiently sensitized by (3)MLCT states of the metalloligands in the visible-light region. The energy transfer rates for the complexes are generally in the order Nd > Yb, which is due to the better matching between (3)MLCT states of Ru(II)/Ir(III) metalloligands and densely distributed excited states of Nd(III) ions. Long decayed lifetimes on a μs scale and high quantum yields up to 1% are obtained in these lanthanide complexes, suggesting that the Ru(II)/Ir(III) metalloligands can serve as a good visible light harvesting antenna to efficiently sensitize Ln(III)-based NIR luminescence.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chemistry, Organic / methods
  • Energy Transfer
  • Ions
  • Iridium / chemistry*
  • Lanthanoid Series Elements / chemistry
  • Ligands
  • Light
  • Luminescence
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Neodymium / chemistry*
  • Photochemistry / methods
  • Quantum Theory
  • Ruthenium / chemistry*
  • Spectrometry, Mass, Electrospray Ionization
  • Spectroscopy, Near-Infrared / methods*
  • Ytterbium / chemistry*

Substances

  • Ions
  • Lanthanoid Series Elements
  • Ligands
  • Neodymium
  • Iridium
  • Ruthenium
  • Ytterbium