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2D materials like graphene oxide (GO) based free-standing membranes, although have shown excellent salt rejection at short time scales, suffer from structural stability and swelling on prolonged use.

Copper-based polyoxometalate-immobilized freestanding carbon nanotube constructs exhibit exponential increase in EMI shielding with conductivity triggered through the host–guest electrostatic assembly between POMs and CNT.

A novel complex catalyst, POP-palladium(II), has been synthesized. The developed catalyst has been characterized by XRD, EDX, scanning electron microscopy (FE-SEM), HR-TEM, FTIR spectroscopy, UV-vis spectroscopy, TGA and BET isotherm analysis. The reactivity of the incorporated palladium(II) catalyst was tested in the in situ carbonylation of aryl iodides and secondary cyclic amines to the respective α-ketoamides at 80 °C. A large number of aryl iodides combined with CO followed by 2° amines can generate the corresponding α-ketoamides with high selectivity. This Pd(II) complex catalyst exhibits superb catalytic activities and can also be easily recovered after the reaction by an easy filtration method. The catalyst could be reused for up to six consecutive cycles without much loss in its activity.

Novel polystyrene incorporated Palladium (II) catalyst was developed and well characterized. The efficiency of the supported Pd(II) catalytic material was checked for double carbonylation reaction of 2° amines and aryl iodides to their corresponding α-ketoamides under high pressure reaction conditions. The reaction was carried out in 60 psi carbon monoxide pressure. An extensive variety of aryl iodides in combination with 2° amines in presence of carbon monoxide can produce the respective α-ketoamides with superb chemoselectivity. Effect of solvents, bases, time and amount of catalyst for the production of α-ketoamides were reported. This supported Pd(II)complex was highly catalytically active and recyclable. The developed catalytic material was regenerated by filtration. It could be recycled further six times with no such profound loss in its activity.

Hydrodeoxygenation process is a potential route for upgrading biofuel intermediates, like vanillin, which is obtained in huge quantities through the chemical treatment of the abundant lignocellulosic biomass resources of nature, and this is attracting increasing attentions over the years. Herein, we report the grafting of palladium nanoparticles at the surface of porous organic polymer Pd-PDVTTT-1 synthesized through the co-condensation of 1,3,5-triallyl-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione and divinylbenzene in the presence of radical initiator under solvothermal reaction conditions. The Pd-PDVTTT-1 material has been characterized thoroughly by powder X-ray diffraction, nitrogen sorption, ultra-high-resolution transmission electron Microscopy, Fourier-transform infrared spectroscopy, 13C MAS NMR, and X-ray photoelectron spectroscopy analyses. High surface area together with good thermal stability of the Pd-PDVTTT-1 material has motivated us to explore its potential as heterogeneous catalyst in the hydrodeoxygenation of vanillin for the production of upgraded biofuel 2-methoxy-4-methylphenol in almost quantitative yield and high selectivity (94%).

Mesoporous zirconium oxophosphate (MZrP-1) composed of porous interconnected network and high specific surface area has been synthesized by using Pluronic P123 as template under evaporation-induced self-assembly (EISA) method. The prepared mesoporous material has been characterized by small-angle powder X-ray diffraction, UHR-TEM (Ultra-high Resolution-Transmission Electron Microscopy) image analysis, and N2 adsorption-desorption, FTIR (Fourier-transform Infrared Spectroscopy) and FE-SEM (Field Emission-Scanning Electron Microscopy) analysis. Mesoporous MZrP-1 catalyst exhibited excellent catalytic activity for the synthesis of cyclic acetals from glycerol and cyclic carbonates from epoxide as starting under solvent-free green conditions. High surface area and abundant acid sites present at the surface of the mesoporous zirconium oxophosphate is responsible for high catalytic activity. The catalyst can be reusable for several reaction cycles without any significant loss in its catalytic activity.

Silica coated NiFe2O4 NPs has been synthesized. It has been characterized by XRD, TEM, SEM-EDX and FT-IR. The catalytic activity of the Silica coated NiFe2O4 NPs has been tested for the S-arylation reaction in water with high yield. In this reaction water was used as the green solvent. The effects of solvents, reaction time and catalyst amount for the reaction was reported. This catalyst showed excellent catalytic activity and recyclability. The Silica coated NiFe2O4 NPs catalyst could be easily recovered by filtration and reused more than five times without appreciable loss of its initial activity.

CO2 fixation reaction is one of the most challenging chemical transformations not only in the context of environmental remediation but also for effective utilization of abundant carbon sources in nature. Here, we have stabilized palladium nanoparticles (NPs) at the surfaces of a hypercrosslinked porous polymer bearing carbazole and α,α′-dibromo-p-xylene monomeric units to obtain a Pd@HMP-1 nanocatalyst. The material has been thoroughly characterized by powder XRD, high-resolution (HR)-TEM, field-emission (FE)-SEM, Brunauer–Emmett–Teller (BET), thermogravimetric (TGA), and FTIR analysis. Pd@HMP-1 showed excellent catalytic activity towards formylation of amines by carbon dioxide fixation under mild reaction conditions. The high surface area and nitrogen-rich porous surface make the polymer a suitable support for the palladium nanoparticles and endow it with high recycling efficiency in this CO2 fixation reaction.

Nitrogen affluent mesoporous polymeric material was synthesized as a novel support. Ag nanoparticles were finely dispersed at the mesoporous polymer via post-synthetic chemical grafting ove...

A new organic–inorganic hybrid iron phosphonate material (FePO-1-2) has been synthesized hydrothermally using etidronic acid (1-hydroxyethylidene-1,1-diphosphonic acid) as an organophosphorus precursor. Under optimized reaction conditions the synthesis has been carried out hydrothermally for 3 days at 180 °C temperature at near neutral pH. The material has been characterized thoroughly by various techniques and its crystal structure has been indexed to a new orthorhombic phase with unit cell parameters of a = 10.995 A, b = 10.395 A, c = 11.793 A, and α = β = γ = 90°. The considerably good Brunauer–Emmett–Teller (BET) surface area of 236 m2 g–1, pore volume of 0.229 cm3 g–1, and robust nature of FePO-1-2 have motivated us to explore its catalytic activity in liquid phase partial oxidation reactions under green conditions. FePO-1-2 exhibits excellent catalytic activity (96% product selectivity, 72% conversion) for selective liquid phase oxidation of cyclohexanone to adipic acid in the presence of molecular ...

Ruthenium nanoparticles embedded on a mesoporous poly-melamine-formaldehyde material (Ru@mPMF) has been synthesized and characterized by powder XRD, HRTEM, TGA, SEM, EDS, UV–vis diffuse reflection spectroscopy (DRS), Raman spectroscopy, XPS and N 2 adsorption/desorption study. The Ru@mPMF catalyst was excellent for selective oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) in toluene. Moreover, this catalyst is easily recoverable and it is reusable upto six cycles without notable decrease in its catalytic activity. Profoundly scattered and firmly bound Ru-NPs sites in mPMF might be engaged for the excellent performance of the material. Due to strong binding with the functional groups of the polymer, no indication of ruthenium leaching was there during the reaction. This suggests the actual heterogeneous nature of the material.

We have designed a new mesoporous SBA-15 supported chiral Fe(III)–salen material (Fe@SBSAL) having high BET surface area and porosity. The material showed excellent catalytic efficiency in regio- and enantioselective (ee > 99%) asymmetric ring opening (ARO) of racemic meso- and terminal-epoxides with various anilines at room temperature under solvent-free conditions within 1–3 h reaction time.

Zinc (II) incorporated porous organic polymer catalyst, Zn@BBAPA has been designed, synthesized and characterized thoroughly by XRD, EDX, SEM, HR-TEM, FTIR spectra, UV–vis spectra, TGA and N2 absorption desorption isotherm. An eco-friendly porous Zn@BBAPA catalyst exhibits highly efficient catalytic performance for the production of α-alkylidene cyclic carbonates by using propargylic alcohols viaCO2 fixation.In addition the catalyst shows outstanding efficiency for the synthesis of various dicoumarol derivatives in green solvent medium (water)from 4-hydroxycoumarin and aromatic aldehydes. Presence of super hydrophobic nature and electron-donation characterof NH2 groups of BBA framework with high surface area is main aspect to be responsible for elevated catalytic performance as well as improvement in catalyst stability and enabling a good recyclability.

We have designed a new mesoporous SBA-15 supported chiral Fe(III)–salen material (Fe@SBSAL) having high BET surface area and porosity. The material showed excellent catalytic efficiency in regio- and enantioselective (ee > 99%) asymmetric ring opening (ARO) of racemic meso- and terminal-epoxides with various anilines at room temperature under solvent-free conditions within 1–3 h reaction time.