A novel dichromate-sensitive fluorescent nano-chemosensor using new functionalized SBA-15

A novel fluorescence nano-chemosensor for Cr ₂O ₇ ^2- anion has been developed by assembly of fluorescent aluminum complex of 8-hydroxyquinoline (AlQ _x) within the channels of modified SBA-15. SBA-SPS-AlQ _x shows a fluorescence emission at 486nm. The observed remarkable fluorescence of SBA-SPS-AlQ _x quenches in presence of Cr ₂O ₇ ^2- anion. The results showed that this fluorescent nano-material can be a useful chemo-sensor for determination of dichromate anions in aqueous solutions. The linear detecting range of fluorescent nano-chemosensor for Cr ₂O ₇ ^2- anion was 0.16-2.9μmolL ^-1. The lowest limit of detection (LDL) was also found to be 0.2ngmL ^-1 in aqueous solutions. SBA-SPS-AlQ _x showed selectively and sensitively fluorescent quenching response toward Cr ₂O ₇ ^2- ion in comparison with I ₃ ^-, NO ₃ ^-, CN ^-, CO ₃ ^2-, Br ^-, Cl ^-, F ^-, H ₂PO ₄ ^- and SO ₄ ^2- ions, which was because of the higher stability of its inorganic complex with dichromate ion.