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Hg(II) contamination in water resources is one of the major health issues in keeping the purity standard of the municipal water supply. Herein, we report a new mesoporous sensor probe material SBA-ABZ-PEA having a 2D-hexagonally ordered mesoporous framework bearing covalently bonded fluorescent sites, and this has been synthesized through a two-step post-synthesis grafting route. A pure silica mesoporous SBA-15 material has been functionalized with (3-chloropropyl)triethoxysilane (ClPTES) to obtain chloro-functionalized SBA-15, which was further reacted with 4-aminobenzaldehyde followed by treatment with 2-(2-pyridyl)-ethylamine resulting in functionalized 2D-hexagonal mesoporous sensor probe SBA-ABZ-PEA. Small angle PXRD, N2 adsorption/desorption, HRTEM, TGA, and FT-IR studies have been carried out to characterize these materials. Our experimental results suggested successful grafting of the organic moiety on the SBA-15 surface along with preservation of mesoporosity throughout the grafting process. Photoluminescence measurements were carried out in the aqueous suspension of SBA-ABZ-PEA in the presence of different metal cations, like NaI, MgII, AlIII, KI, CaII, MnII, CoII, CuII, ZnII, CdII, PbII, and HgII. This result revealed that, among the various metal-ions, the emission intensity of the mesoporous sensing probe material SBA-ABZ-PEA has been dramatically quenched in the presence of the HgII ion. To check the sensitivity of the sensor probe, the fluorescence emission was also studied in the presence of different concentrations of HgII ions. A perfect linear plot between the concentrations of HgII ions in the aqueous medium with their corresponding fluorescence intensities with a detection limit of 1.2 × 10–6 M has been observed.

Two new hybrid compounds based on phosphomolybdates, namely (NHEPH 2 ) 5 [Ni II (P 4 Mo 6 O 31 ) 2 ]Á6H 2 O (1) and {(NHEPH 2 ) 2 [Co II (H 2 O) 6 ]}[P 2 Mo 5 O 23 ]Á2H 2 O (2) (NHEP = N-(2-hydroxyethyl)-piperazine), have been synthesized under hydrothermal conditions and characterized by elemental analyses, IR, TGA, single crystal X-ray diffraction and PXRD studies. In compound 1, Ni(II) is sandwiched between two {P 4 Mo 6 O 31 } 6À clusters and the residual negative charges are neutralized by NHEPH 2 2+ . In compound 2, the [P 2 Mo 5 O 23 ] 6À ion exists as a discrete moiety and the negative charges are compensated by both [Co(H 2 O) 6 ] 2+ and NHEPH 2 2+ . The extensive hydrogen bonding involving the organic cations and water molecules yielded three-dimensional (3D) open framework structures in these systems. These phosphomolybdate based compounds showed good catalytic efficiency in heterogeneous oxidation of styrene in the presence of an environmentally benign oxidant, H 2 O 2 , under mild conditions.Again, the construction of a simple metal-organic framework system can also be achieved by using simple transition metal cations and/or organic amine cations to balance the charge on the POM units. In this paper, we report two inorganic-organic hybrid materials formed from phosphomolybdates, namely

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Heterogeneous catalysts play a key role in addressing the economic and environmental issues of the chemical industry due to their several advantages, like ease of product separation, work-up and high recycling efficiency. Herein, we report the synthesis of a robust manganese(iv)-containing aluminophosphate material (MnAPO-5), with an AFI framework topology. This material has been characterized thoroughly by powder XRD, XPS, UHR TEM, FE SEM, P CP MAS NMR, atomic absorption spectroscopy, UV-visible spectroscopy and TGA. The Mn-containing microporous material has been employed as a heterogeneous catalyst for the oxidation of styrene and the synthesis of adipic acid from cyclohexanone in the presence of tert-butyl hydroperoxide (TBHP) as the oxidant in air and it displayed very high recycling efficiency.