Activation of C−H bonds of hydrocarbons is one of the thrust areas of research over the years. Designing a robust catalyst, which can work efficiently under ecofriendly conditions for this reaction still remains a big challenge today. Highly dispersed aggregation-free silver nanoparticles (AgNPs) are immobilized over 2D hexagonally ordered functionalized mesoporous silica material via surface thioether functionalization, and the resulting supported AgNPs (AgMS) displayed environmentally benign selective oxidation of C−H bonds of the aliphatic and monocyclic hydrocarbons into their respective carbonyl compounds. AgNPs-supported mesoporous materials are characterized by powder X-ray diffraction, nitrogen adsorption−desorption, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The AgMS material retains mesoporosity with a narrow pore size distribution (D ∼ 5.7 nm) together with a high BET surface area of 844 m 2 g −1 after loading of AgNPs. The AgMS catalyst exhibited excellent activity toward liquid phase oxidation of C−H bonds under solvent-free and base-free neat conditions using molecular oxygen as the oxidant. This methodology was successfully applied for the oxidation of substituted toluene, benzylic C−H bonds, and cycloalkanes with very good conversion and selectivity. Moreover, the hydrocarbon conversion and selectivity for the carbonyl products in this partial oxidation reaction have been retained after six reaction cycles. Therefore, immobilization of AgNPs at the surface of ordered mesoporous silica offers a very efficient route in designing a readily separable, reusable, very robust, and promising catalyst for C−H bond activation under eco-friendly reaction conditions.

The urea oxidation reaction (UOR) is an excellent alternative to the sluggish oxygen evolution reaction (OER) as an anode reaction for hydrogen generation via electrochemical water splitting. Here, a porphyrin-based conjugated porous polymer (CPP) has been developed through the polycondensation reaction of 2,6-diformyl-4-methylphenol and pyrrole (DMP-POR). The nickel(II) complex of this conjugated polymer Ni-DMP-POR shows efficient UOR in an alkaline medium. The as-synthesized materials were characterized by solid-state 13 C CP-MAS, thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The porous property of the materials was characterized by N 2 adsorption/desorption isotherms at 77 K. Both DMP-POR and Ni-DMP-POR showed excellent thermal stability. The Ni-DMP-POR exhibits very good UOR in 1 M KOH and 0.33 M urea with an overpotential of 260 mV at 10 mA cm −2 and a Tafel slope of 48 mV dec −1 . The catalyst also shows excellent chronoamperometric and chronopotentiometric stability, suggesting its future scope in sustainable hydrogen production from wastewater resources.

Electrolysis of water is emerging as a potential technique for producing green hydrogen. However, the large overpotential due to sluggish kinetics involved with the oxygen evolution reaction (OER) coerces scientific...

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To date, the fabrication of multifunctional nanoplatforms based on a porous organic polymer for electrochemical sensing of biorelevant molecules has received considerable attention in the search for a more active, robust, and sensitive electrocatalyst. Here, in this report, we have developed a new porous organic polymer based on porphyrin (TEG-POR) from a polycondensation reaction between a triethylene glycol-linked dialdehyde and pyrrole. The Cu(II) complex of the polymer Cu-TEG-POR shows high sensitivity and a low detection limit for glucose electro-oxidation in an alkaline medium. The characterization of the as-synthesized polymer was done by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and 13C CP-MAS solid-state NMR. The N2 adsorption/desorption isotherm was carried out at 77 K to analyze the porous property. TEG-POR and Cu-TEG-POR both show excellent thermal stability. The Cu-TEG-POR-modified GC electrode shows a low detection limit (LOD) value of 0.9 μM and a wide linear range (0.001–1.3 mM) with a sensitivity of 415.8 μA mM–1 cm–2 toward electrochemical glucose sensing. The interference of the modified electrode from ascorbic acid, dopamine, NaCl, uric acid, fructose, sucrose, and cysteine was insignificant. Cu-TEG-POR exhibits acceptable recovery for blood glucose detection (97.25–104%), suggesting its scope in the future for selective and sensitive nonenzymatic glucose detection in human blood.