Binita Nanda

Transition metal/metal oxide modified MCM-41 for pollutant degradation and hydrogen energy production: a review

In recent years, metal/metal oxide functionalized mesoporous materials have received increasing attention in science and technology due to their fascinating properties, such as a large surface area, mesoscopic bulky shape, and interconnected porous structures enabling them to be one of the most promising materials for catalysis and photo catalysis. This review summarizes the recent developments in design, preparation and applications of transition metal/metal oxide promoted MCM-41 for production of hydrogen energy and removal of aqueous pollutants. After a brief introduction of these materials and synthetic strategies, their characterizations and applications in aqueous pollutant degradation by photocatalysis/photo-Fenton processes and H2 energy production by photocatalytic water splitting are summarized. Finally, the future perspectives directions for this promising field are also discussed.

Cu@CuO promoted g-C3N4/MCM-41: an efficient photocatalyst with tunable valence transition for visible light induced hydrogen generation

A series of ternary Cu@CuO–g-C3N4/MCM-41 photocatalysts have been synthesized by varying the percentage of Cu using simple impregnation and co-condensation methods. The physico-chemical characterization of all the samples was determined using XRD, FTIR, UV-Vis DRS, PL, N2 ads–des studies, SEM and XPS HRTEM, EDAX, EIS and MS. The structural advantages of MCM-41, allow the uniform distribution of g-C3N4 and coexistence of Cu2+ along with Cu0 without using a reducing agent. The presence of g-C3N4 helps to shift the Fermi level of CuO towards more negative values due to accumulation of photogenerated electrons on the surface. It favours charge separation by creating a Schottky barrier at the junction. The 4 wt% Cu loaded over g-C3N4/MCM-41 exhibits a maximum 750 μmol 2 h−1 of H2 evolution under visible light irradiation with an apparent energy conversion efficiency of 24.8%. The enhancement in catalytic activity has been explained on the basis of synergism between g-C3N4 and Cu2+ and the SPR effect of Cu which also acts as a co-catalyst present on the surface of photocatalysts.

Fabrication of Amine and Zirconia on MCM‐41 as Acid–Base Catalysts for the Fixation of Carbon Dioxide

Highly porous catalysts based on MCM‐41 with both acidic and basic sites such as ZrO2 as an acid and (3‐aminopropyl)triethoxysilane as a mild base are fabricated and characterized thoroughly by using XRD, SEM, thermogravimetric analysis, temperature‐programmed reduction, desorption, oxidation, BET surface area analysis, energy‐dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, and IR spectroscopy. This catalyst shows a synergistic effect for the activation of epoxide as well as CO2 to synthesize cyclic carbonates. The presence of the free amine functional group activates CO2 by absorption, whereas the presence of Zr metal activates the epoxide ring. The effect of the amine and catalyst loading on the cycloaddition reaction was studied. Additionally, the cycloaddition reaction proceeds under solvent‐free and mild conditions, and the catalysts are recyclable.