title: Near-infrared (NIR) emitting Nd/Yb(III) complexes sensitized by MLCT states of Ru(II)/Ir(III) metalloligands in the visible light region.
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.
authors.affiliation: MOE Laboratory of Bioinorganic and Synthetic Chemistry, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China. panm@mail.sysu.edu.cn shaog@mail.sysu.edu.cn cesscy@mail.sysu.edu.cn.
authors.forename: Lu-Yin
authors.initials: LY
authors.lastname: Zhang
authors.forename: Ya-Jun
authors.initials: YJ
authors.lastname: Hou
authors.forename: Mei
authors.initials: M
authors.lastname: Pan
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.forename: Yi-Xuan
authors.initials: YX
authors.lastname: Zhu
authors.forename: Shao-Yun
authors.initials: SY
authors.lastname: Yin
authors.forename: Guang
authors.initials: G
authors.lastname: Shao
authors.forename: Cheng-Yong
authors.initials: CY
authors.lastname: Su
mesh_terms: D002625:Chemistry, Organic / Q000379:methods; D004735:Energy Transfer; D007477:Ions; D007495:Iridium / Q000737:chemistry*; D028581:Lanthanoid Series Elements / Q000737:chemistry; D008024:Ligands; D008027:Light; D049449:Luminescence; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009354:Neodymium / Q000737:chemistry*; D010777:Photochemistry / Q000379:methods; D011789:Quantum Theory; D012428:Ruthenium / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D015018:Ytterbium / Q000737:chemistry*
chemical_list: D007477:Ions; D028581:Lanthanoid Series Elements; D008024:Ligands; D009354:Neodymium; D007495:Iridium; D012428:Ruthenium; D015018:Ytterbium