Phosphorescent chemosensor for Hg2+ based on an iridium(iii) complex coordinated with 4-phenylquinazoline and carbazole dithiocarbamate

Abstract

A highly selective and colorimetric phosphorescent turn-on chemosensor for Hg²⁺ based on an iridium(III) complex Ir(pqz)₂(cdc) (pqzH = 4-phenylquinazoline, Nacdc = sodium carbazole dithiocarbamate) was realized. The photograph of Ir(pqz)₂(cdc)under ultraviolet light exhibited an emitting color change from red to yellow without and with Hg²⁺ in an acetonitrile (MeCN) solution, and it can also serve as a highly selective chemosensor for Hg²⁺ with naked-eye detection. Upon addition of a tetrahydrofuran (THF) solution of Hg²⁺, the dichloromethane (DCM) solution of Ir(pqz)₂(cdc) gave a visual color change and significant luminescent quenching. When MeCN was added, a new emission peak at 562 nm emerged, which constituted a selective MeCN phosphorescent chemosensor.