Amine-decorated Zirconium Based Metal Organic Framework for Ultrafast Detection of 2,4,6-Trinitrophenol in Aqueous Samples

An amine-decorated zirconium based metal organic framework (MOF) UiO-66-NH₂ with rod shape morphology was synthesized by solvothermal process using 2-aminoterephthalic acid as an organic linker. Crystallinity of synthesized MOF material was confirmed with PXRD technique. MOF was employed as selective and sensitive sensor for ultra-trace detection of 2,4,6-trinitrophenol (TNP) in aqueous matrix, even in coexistence with other competitive nitroaromatic analytes. High value of Stern-Volmer quenching constant K_sv (1.106 × 10⁵ M^{- 1}), plausible photoluminescent quenching efficiency (97.8%) and lower detection limit (0.95 µM/217ng mL^{- 1}) ascertained extraordinary sensitivity of developed MOF for TNP. Density functional theory calculations and electrostatic interactions (i.e. ionic interaction, H-bonding and π-π interaction) indicated that electron and energy transfer processes play a key role in turn-off quenching response of UiO-66-NH₂ sensor. Spiked real samples were analysed to validate the developed method, which satisfactorily established the developed MOF sensor as an efficient tool for analysis.