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

A novel fluorescence nano-chemosensor for Cr2O72− anion has been developed by assembly of fluorescent aluminum complex of 8-hydroxyquinoline (AlQx) within the channels of modified SBA-15. SBA-SPS-AlQx shows a fluorescence emission at 486 nm. The observed remarkable fluorescence of SBA-SPS-AlQx quenches in presence of Cr2O72− 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 Cr2O72− anion was 0.16–2.9 μmol L−1. The lowest limit of detection (LDL) was also found to be 0.2 ng mL−1 in aqueous solutions. SBA-SPS-AlQx showed selectively and sensitively fluorescent quenching response toward Cr2O72− ion in comparison with I3−, NO3−, CN−, CO32−, Br−, Cl−, F−, H2PO4− and SO42− ions, which was because of the higher stability of its inorganic complex with dichromate ion.