Fluorescence Based Comparative Sensing Behavior of the Nano-Composites of SiO2 and TiO2 towards Toxic Hg2+ Ions

Abstract

We have synthesized sulfonamide based nano-composites of SiO2 and TiO2 for selective and sensitive determination of toxic metal ion Hg2+ in aqueous medium. Nano-composites (11) and (12) were morphologically characterized with FT-IR, solid state NMR, UV-vis, FE SEM, TEM, EDX, BET, pXRD and elemental analysis. The comparative sensing behavior, pH effect and sensor concentrations were carried out with fluorescence signaling on spectrofluorometer and nano-composites (11) and (12), both were evaluated as “turn-on” fluorescence detector for the toxic Hg2+ ions. The LODs were calculated to be 41.2 and 18.8 nM, respectively of nano-composites (11) and (12). The detection limit of TiO2 based nano-composites was found comparatively lower than the SiO2 based nano-composites.

Sulfonamide functionalized silica nano-composite: characterization and fluorescence “turn-on” detection of Fe3+ ions in aqueous samples

“…1c, while another band around + n HCl 1538 cm −1 was assigned to -NH vibrations. Thus, the FT-IR spectra confirmed the binding of sulfonamide moiety on APTES@SiO 2 nanoparticles [43] (detailed description of the FT-IR spectra of both SiO 2 and APTES@SiO 2 is given in our previous manuscript) [44].…”