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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.

SUBMITTER: Ekta

PROVIDER: S-EPMC8621696 | biostudies-literature |

REPOSITORIES: biostudies-literature

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