Ultra-Sensitive Detection of Pyridine in Water Using Zinc Porphyrin Incorporated in a Transparent Hydrophobic Film

In this study, we investigated the axial coordination reaction between pyridine and zinc meso-tetra(4-sulfonatophenyl)porphyrin (ZnTPPS) incorporated in a transparent layered double hydroxide (LDH) film modified with 1-decanesulfonate (C10S) in an aqueous solution. The equilibrium constant (\({K}_{11}\)) of the axial coordination reaction between pyridine and ZnTPPS incorporated in the transparent ZnTPPS/C10S/LDH film was approximately 260 times that of the corresponding reaction in an aqueous solution. The hydrophobisation of the LDH interlayer space by C10S, which led to the elimination of water molecules surrounding ZnTPPS and enabled the accumulation of pyridine molecules, was responsible for such a significant increase in the \({K}_{11}\) value. The developed film can detect pyridine in aqueous solutions with ultra-high sensitivity in the order of 10−5 mol/L through changes in the colour tone, which is comparable to the molecular detection ability of insect antennae. The sensing response was also observed at pyridine concentrations as low as 10−9 mol/L.

Ultra-Sensitive Detection of Pyridine in Water Using Zinc Porphyrin Incorporated in a Transparent Hydrophobic Film

In this study, we investigated the axial coordination reaction between pyridine and zinc meso-tetra(4-sulfonatophenyl)porphyrin (ZnTPPS) incorporated in a transparent layered double hydroxide (LDH) film modified with 1-decanesulfonate (C10S) in an aqueous solution. The equilibrium constant (K11) of the axial coordination reaction between pyridine and ZnTPPS incorporated in the transparent ZnTPPS/C10S/LDH film was approximately 260 times that of the corresponding reaction in an aqueous solution. The hydrophobisation of the LDH interlayer space by C10S, which led to the elimination of water molecules surrounding ZnTPPS and enabled the accumulation of pyridine molecules, was responsible for such a significant increase in the K11 value. The developed film can detect pyridine in aqueous solutions with ultra-high sensitivity in the order of 10−5 mol/L through changes in the colour tone, which is comparable to the molecular detection ability of insect antennae. The sensing response was also observed at pyridine concentrations as low as 10−9 mol/L.

Counterintuitive Single-Molecule Magnet Behaviour in Two Polymorphs of One-Dimensional Compounds Involving Chiral BINOL-Derived Bisphosphate Ligands

The coordination reaction of the [Dy(hfac)3(H2O)2] units (hfac− = 1,1,1,5,5,5-hexafluoroacetylacetonate) with the [8′-(Diphenoxylphosphinyl)[1,1′-binaphthalen]-8-yl]diphenoxylphosphine oxide ligand (L) followed by a crystallisation in a 1:3 CH2Cl2:n-hexane solvent mixture led to the isolation of a new polymorph of formula [(Dy(hfac)3((S)-L))3]n (1). The X-ray structure on single crystal of 1 revealed the formation of a mono-dimensional coordination polymer with three crystallographically independent DyIII centres, which crystallised in the polar chiral P21 space group. Ac magnetic measurements highlighted single-molecule magnet behaviour under both zero and 1000 Oe applied magnetic field with magnetic relaxation through quantum tunneling of the magnetisation (QTM, zero field only) and Raman processes. Despite the three crystallographically independent DyIII centres adopting a distorted D4d coordination environment, a single slow magnetic relaxation contribution was observed at a slower rate than its previously studied [(Dy(hfac)3((S)-L))]n (2) polymorph.

Field-Induced Single-Molecule Magnets of Dysprosium Involving Quinone Derivatives

The coordination reaction of the [Dy(hfac)3(H2O)2] units (hfac− = 1,1,1,5,5,5-hexafluoroacetylacetonate) with the two quinone-based derivatives 4,7-di-tert-butyl-2-(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-ylidene)benzo[d][1,3]dithiole-5,6-dione (L1) and 7,8-dithiabicyclo[4.2.0]octa-1,5-diene-3,4-dione,2,5bis(1,1-dimethylethyl) (L2) led respectively to the complexes [Dy(hfac)3(H2O)(L1)] (1) and [Dy(hfac)3(H2O) (L2)]⋅(C6H14)(CH2Cl2) (2)⋅(C6H14)(CH2Cl2). X-ray structures on single crystal of 1 and 2⋅(C6H14)(CH2Cl2) revealed the coordination of the DyIII on the bischelating oxygenated quinone site and the formation of dimeric species through hydrogen bonds. Ac magnetic measurements highlighted field-induced single-molecule magnet behavior with magnetic relaxation through a Raman process.

Manganese Schiff Base Immobilized on Graphene Oxide Complex and Its Catalysis for Epoxidation of Styrene

Immobilization of metal complexes on solid supports is an efficient approach to circumvent the drawbacks of homogeneous catalysis. In this paper, using graphene oxide as carrier, manganese Schiff base supported on graphene oxide (Salen Mn-GO) was prepared through aminosilane covalent modification as well as salicylaldehyde condensation and coordination reaction. The structures and properties of the composite were examined by FT-IR, XRD, XPS, TEM, TG techniques, and the catalytic performance of Salen Mn-GO in styrene epoxidation was explored. The effects of catalyst and styrene amount as well as that of reaction time on the performance of the catalyst were investigated. The results showed that Salen Mn-GO has excellent catalytic activity and reusability for epoxidation of styrene in the presence of hydrogen peroxide. Finally, the mechanism of styrene epoxidation catalyzed by Salen Mn-GO has been preliminarily discussed.

Manganese Schiff Base Immobilized on Graphene Oxide Complex and Its Catalysis for Epoxidation of Styrene

Immobilization of metal complexes on solid supports is an efficient approach to circumvent the drawbacks of homogeneous catalysis. In this paper, using graphene oxide as carrier, manganese Schiff base supported on graphene oxide (Salen Mn-GO) was prepared through aminosilane covalent modification as well as salicylaldehyde condensation and coordination reaction. The structures and properties of the composite were examined by FT-IR, XRD, XPS, TEM, TG techniques, and the catalytic performance of Salen Mn-GO in styrene epoxidation was explored. The effects of catalyst and styrene amount as well as that of reaction time on the performance of the catalyst were investigated. The results showed that Salen Mn-GO has excellent catalytic activity and reusability for epoxidation of styrene in the presence of hydrogen peroxide. Finally, the mechanism of styrene epoxidation catalyzed by Salen Mn-GO has been preliminarily discussed.

Manganese Schiff Base Immobilized on Graphene Oxide Complex and Its Catalysis for Epoxidation of Styrene

Immobilization of metal complexes on solid supports is an efficient approach to circumvent the drawbacks of homogeneous catalysis. In this paper, using graphene oxide as carrier, manganese Schiff base supported on graphene oxide (Salen Mn-GO) was prepared through aminosilane covalent modification as well as salicylaldehyde condensation and coordination reaction. The structures and properties of the composite were examined by FT-IR, XRD, XPS, TEM, TG techniques, and the catalytic performance of Salen Mn-GO in styrene epoxidation was explored. The effects of catalyst and styrene amount as well as that of reaction time on the performance of the catalyst were investigated. The results showed that Salen Mn-GO has excellent catalytic activity and reusability for epoxidation of styrene in the presence of hydrogen peroxide. Finally, the mechanism of styrene epoxidation catalyzed by Salen Mn-GO has been preliminarily discussed.

Manganese Schiff Base Immobilized on Graphene Oxide Complex and Its Catalysis for Epoxidation of Styrene

Immobilization of metal complexes on solid supports is an efficient approach to circumvent the drawbacks of homogeneous catalysis. In this paper, using graphene oxide as carrier, manganese Schiff base supported on graphene oxide (Salen Mn-GO) was prepared through aminosilane covalent modification as well as salicylaldehyde condensation and coordination reaction. The structures and properties of the composite were examined by FT-IR, XRD, XPS, TEM, TG techniques, and the catalytic performance of Salen Mn-GO in styrene epoxidation was explored. The effects of catalyst and styrene amount as well as that of reaction time on the performance of the catalyst were investigated. The results showed that Salen Mn-GO has excellent catalytic activity and reusability for epoxidation of styrene in the presence of hydrogen peroxide. Finally, the mechanism of styrene epoxidation catalyzed by Salen Mn-GO has been preliminarily discussed.