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Read Full License spectral overlap, respectively. Hence, synthesized composite is veri ed as multi-component system to act as excellent photocatalyst as well as uorescent sensor.

A novel SnO2@Cu3(BTC)2 composite was synthesized using a quick and affordable bottom-up approach via impregnation of SnO2 nanoparticles into the porous Cu3(BTC)2 metal-organic framework (MOF). The photocatalytic degradation of the methylene blue (MB) dye has been studied for the first time using this novel recyclable SnO2@Cu3(BTC)2 composite. It was found that SnO2@Cu3(BTC)2 composite photo catalytically degrades methylene blue (MB) dye with a degradation efficiency of 85.12% within 80 min under solar irradiation. The most appropriate benefit of this composite is the easy recyclability up to numerous cycles with retention of its photocatalytic activity. Therefore, this cheaper and greener composite photocatalyst is more suitable for large-scale industrial applications than the traditional photocatalysts employed in the degradation of MB dye. Furthermore, this composite has also been investigated as a fluorescence sensor for the detection of nitroaromatic compounds (NACs). It was observed that the 88.2% quenching of the intense fluorescent signal of this composite happens in the presence of 2,4,6-trinitrophenol (TNP) showing it incredibly selectivity towards TNP with no interference of other NACs. With a detection limit of 2.82 µM, this composite exhibits outstanding sensitivity towards TNP. The Stern-Volmer plot for TNP is linearly fitted displays large quenching coefficient, correlation coefficient, and linear ranges KSV = 1.04x104 M-1, R2 = 0.9901, and 0-10 µM, respectively. This quenching response of this composite towards TNP was well-explained by the two mechanisms: one is photo-induced electron transfer (PET), and the other is fluorescence resonance energy transfer (FRET), in addition to theoretical calculations based on density functional theory (DFT). Our findings imply that the synthetic composite can be used as a superior fluorescence sensor and photocatalyst.

A facile bottom up technique is opted for the synthesis of novel composite SnO2@Zn-BTC. This synthesized composite is fully characterized by Fourier Transform Infrared (FTIR) Spectroscopy, Powder X-Ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS), and Elemental mapping techniques. Optical analysis is done using UV-Visible absorption spectroscopy and fluorescence studies. Further this composite is utilized for the first time to act as a photocatalyst for degradation of MB dye as a test contaminant under sunlight irradiation. This photocatalyst shows degradation efficiency of 89% within 100 min of exposure of sunlight. In addition to that the synthesized composite can be utilized as a fluorescence probe for detection of NACs via ‘turn-off” quenching response. This composite is extremely sensitive towards 3-NA in aqueous medium with quenching efficiency of 75.42 %, which is highest quenching rate till reported. There occurs no interference for detecting 3-NA in the presence of other NACs. The linear fitting of the Stern-Volmer plot for 3-NA shows large quenching constant (KSV) of 0.0115 ppb-1with correlation coefficient R2 = 0.9943 proves higher sensitivity of composite in sensing process. The outstanding sensitivity of composite for 3-NA is proved by low detection limit (LOD) of 25 ppb (0.18 µM). Photoinduced Electron Transfer (PET) and the Fluorescence Resonance Energy Transfer (FRET) are the mechanisms used for clarification of quenching response of PL intensity by NACs via Density functional theory (DFT) theoretical calculations and extent spectral overlap, respectively. Hence, synthesized composite is verified as multi-component system to act as excellent photocatalyst as well as fluorescent sensor.

A novel SnO 2 @Cu 3 (BTC) 2 composite was synthesized using a quick and affordable bottom-up approach via impregnation of SnO 2 nanoparticles into the porous Cu 3 (BTC) 2 metal-organic framework (MOF). The photocatalytic degradation of the methylene blue (MB) dye has been studied for the rst time using this novel recyclable SnO 2 @Cu 3 (BTC) 2 composite. It was found that SnO 2 @Cu 3 (BTC) 2 composite photo catalytically degrades methylene blue (MB) dye with a degradation e ciency of 85.12% within 80 min under solar irradiation. The most appropriate bene t of this composite is the easy recyclability up to numerous cycles with retention of its photocatalytic activity. Therefore, this cheaper and greener composite photocatalyst is more suitable for large-scale industrial applications than the traditional photocatalysts employed in the degradation of MB dye. Furthermore, this composite has also been investigated as a uorescence sensor for the detection of nitroaromatic compounds (NACs). It was observed that the 88.2% quenching of the intense uorescent signal of this composite happens in the presence of 2,4,6-trinitrophenol (TNP) showing it incredibly selectivity towards TNP with no interference of other NACs. With a detection limit of 2.82 µM, this composite exhibits outstanding sensitivity towards TNP. The Stern-Volmer plot for TNP is linearly tted displays large quenching coe cient, correlation coe cient, and linear ranges K SV = 1.04x10 4 M -1 , R 2 = 0.9901, and 0-10 µM, respectively. This quenching response of this composite towards TNP was well-explained by the two mechanisms: one is photoinduced electron transfer (PET), and the other is uorescence resonance energy transfer (FRET), in addition to theoretical calculations based on density functional theory (DFT). Our ndings imply that the synthetic composite can be used as a superior uorescence sensor and photocatalyst. HighlightsUsing a bottom-up approach, a unique SnO 2 @Cu 3 (BTC) 2 composite has been prepared.Experiments demonstrate that this composite degrade 85.12% of methylene blue (MB) dye within 80 minutes.Additionally, this composite also sensitively and selectively detects 2,4,6-trinitrophenol (TNP) in water via turn-off quenching response.The turn-off quenching response of this composite can be explained by photo-induced Electron Transfer (PET) and uorescence Resonance Energy Transfer (FRET) mechanisms.Theoretical density functional theory (DFT) calculations were done to provide strong support to the experimental results.