Novel colorimetric phosphorescent chemodosimeter for Hg~(2+) based iridium(III) complex with phosphonodithioate auxiliary ligand

摘要

A colorimetric phosphorescent iridium(III) complex chemodosimeter (Ir1) for Hg~(2+) has been prepared and confirmed by NMR, MS, and crystal data, which displays a high selectivity and antidisturbance for Hg~(2+) among relevant metal ions. The solution color changed from orange to light yellow as soon as 1 equiv of Hg~(2+) was added. Phosphorescent studies show that the luminescence intensity in 599 nm decreased to ca. 13%, while the luminescence intensity in 465 nm increased to ca. 217%. The ratio of Ir1 responding to Hg~(2+) was determined to be 1:1 by UV-vis absorption and phosphorescent emission measurements. Further study demonstrates the detection limit on phosphorescent response of the sensor to Hg~(2+) is down to 10-6 M range. The mechanism study shows that the interaction between the S atom of ancillary ligand and Hg2+ is responsible for the highly selective and sensitive phosphorescent senor for Hg~(2+).