A highly selective and ratiometric sensor for Hg2+ based on a phosphorescent iridium (III) complex

A new neutral iridium (Ill) complex Ir(TBT)(2)(acac) based on 2-thiophen-2-yl-benzothiazole (TBTH) ligands has been synthesized and characterized. Ir(TBT)2(acac) exhibited color change from red to orange without and with Hg2+, at the same time has a blue shift about 23 nm in fluorescent emission spectra. So it can serve as a highly selective chemodosimeter for Hg2+ with ratiometric and naked-eye detection. The sensor allowed determination of Hg2+ in the working range of 3 mu M-10 mu M with a detection limit of 2.14 mu M. The phosphorescent chemosensor exhibited excellent selectivity and sensitivity for Hg2+ detection. (C) 2012 Elsevier B.V. All rights reserved.