Sensitized near-infrared luminescence of lanthanide complexes by energy transfer from a ruthenium antenna
作者:Subramanian Singaravadivel、Eththilu Babu、Murugesan Velayudham、Kuang-Lieh Lu、Seenivasan Rajagopal
DOI:10.1016/j.poly.2013.05.018
日期:2013.8
The luminescent ruthenium tetrapyrido [3, 2-a:2', 3 ''-c:3 '', 2 ''-h:2''', 3'''-j] phenazine(tpphz) complex acts as a potential bridging ligand with a vacant diimine site, and is used as 'metallo ligand' to make heterodinuclear d-f complexes by attachment of a Ln(dik)(3)) fragment (dik = tta (trifluoro theonyl acetone)) at the vacant site. When Ln = Nd, Yb or Er, the lanthanide centre has low-energy f-f excited states capable of accepting energy from the (MLCT)-M-3 excited state of the Ru(II) centre. Luminescence quenching of the (MLCT)-M-3 Ru(II) center affords sensitized Ln(III) based luminescence in the near-IR region. Nd(III) is found to be the most effective quencher for the (MLCT)-M-3 luminescence of the ruthenium component because of the high density of f-f excited states of the appropriate energy, which makes it a more efficient energy-acceptor compared to the Er and Yb complexes. (C) 2013 Elsevier Ltd. All rights reserved.