A mesoporous silica functionalized by a covalently bound calixarene-based fluoroionophore for selective optical sensing of mercury(II)in water

摘要

With the aim of optical sensing of Hg~(2+)in water,a calixarene bearing two dansyl fluorophores was grafted on a large pore mesoporous silica material(SBA-15)via two long alkyl chains containing triethoxysilane groups.The characterization of the obtained material 2-SBA-15 shows that the organized structure is preserved after the post-grafting procedure.A detailed study of the complexing and fluorescence properties of 2-SBA-15 is reported.The functionalized material is able to reversibly detect Hg~(2+)with a response time of a few seconds and a detection limit of 3.3 x 10~(-7)mol L~(-1)in water.Furthermore,this system offers a high selectivity over several interfering cations(Na~+,K~+,Ca~(2+),Cu~(2+),Cd~(2+),Pb~(2+)).