Hexagonal molybdenum oxide (h-MoO 3 ) nanocrystals with a flower-like hierarchical structure have been successfully synthesized by a solution based self assembly route. The as-synthesized h-MoO 3 was recognized as a photocatalyst for the photocatalytic degradation of methylene blue (MB) under various experimental conditions. Initially, the as-synthesized h-MoO 3 was characterized by different physicochemical techniques in order to study and reveal the structural, functional, morphological, and optical properties. The results indicated that the photocatalyst has a hexagonal crystal structure with an average crystallite size of 46 nm. The morphology analysis has proved that the h-MoO 3 comprises one dimensional (1D) rods with a hexagonal cross section. The possible formation mechanism is proposed as a self assembly process for nucleation and an Ostwald ripening mechanism for particle growth. The optical band gap investigation showed that the E g value of h-MoO 3 (2.94 eV) lies in the visible region and can be an appropriate candidate for visible light photocatalytic application. Furthermore, the experimental observations demonstrate an excellent photocatalytic performance of h-MoO 3 in the degradation of MB under visible light irradiation.

A detailed study on visible light photocatalytic degradation of methylene blue (MB) has been investigated in aqueous heterogeneous media containing hexagonal phase molybdenum oxide (h-MoO3) nanocrystals (NCs) which was identified as a new material for visible light driven photocatalysis. A simple and template-free solution based chemical precipitation method was employed to synthesize h-MoO3 NCs by reacting ammonium heptamolybdate tetrahydrate (AHM) with nitric acid. The formation and growth mechanism of h-MoO3 microstructures was explained. In addition, by annealing the h-MoO3 sample, the phase stability of hexagonal was retained up to 410 °C and showed an irreversible phase transition from hexagonal (h-MoO3) to highly stable orthorhombic phase (α-MoO3). Finally, the photocatalytic activities of h-MoO3 and α-MoO3 samples were evaluated using the degradation of MB, representing an organic pollutant of dye wastewater. The effects of various experimental parameters such as catalyst loading, initial dye concentration, light intensity, and operating temperature were analyzed for the degradation of MB. The results demonstrated that the efficiency of visible light assisted MB degradation using h-MoO3 NCs can be effectively enhanced by catalyst loading, light intensity, and operating temperature. However, the efficiency declined with the increase in initial dye concentration. Optimum conditions for higher photocatalytic performance were recognized as a catalyst loading of 100 mg L(-1), a dye concentration of 12 mg L(-1), a light intensity of 350 mW cm(-2), and an operating temperature of 45 °C.

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Colorimetric and fluorometric detection of copper ion (Cu2+) has attracted much attention because of the biological, environmental and medical significance of the Cu2+ion.

Novel three dimensional cubic Fm3m mesoporous aluminosilicates (AlKIT‐5) with very high structural order and unprecedented loadings of Al in the silica framework have been successfully prepared for the first time by using non ionic surfactant as a template in a highly acidic medium. The obtained materials have been unambiguously characterized in detail by several sophisticated techniques such as XRD, N2 adsorption, HRTEM, HRSEM, EDS, elemental mapping, 27Al MAS NMR, and NH3‐TPD. We also demonstrate that the nature, and the amount of Al incorporation in the silica framework can easily be controlled by simply varying the nH2O/nHCl and the nSi/nAl ratios, and the Al sources in the synthesis gel. Among the Al sources examined, the Al isopropoxide (AiPr) is superior over other Al sources. 27Al MAS NMR results reveal that the amount of tetrahedral Al in the framework can be controlled by simply adjusting the nSi/nAl ratio in the synthesis gel, which increases with increasing the Al incorporation. One of the interesting findings in the work is the increase of the specific surface area, specific pore volume and the pore diameter of AlKIT‐5 with increasing the Al incorporation in the silica framework (up to nSi/nAl ratio of 10) while retaining the well‐ordered three dimensional cage type porous structure, and the mechanism for the unusual behavior has been discussed in detail. Finally, the acidity and the catalytic activity in the acetylation of veratrole of the AlKIT‐5 catalysts have been studied and the results have been compared with the several zeolites catalysts. Among the catalysts examined, AlKIT‐5(10) is found to be superior over the zeolites catalysts such as mordenite, zeolite H‐Y, zeolite H‐β, and ZSM‐5.

Summary: A rapid and eco‐friendly synthesis of poly(butylene succinate) (PBS) using microwaves was developed in the presence of 1,3‐dichloro‐1,1,3,3‐tetrabutyldistannoxane as catalyst. To determine the optimum conditions, the effect of catalyst concentration, bulk vs. solution polymerization, reaction time, temperature, and stoichiometry of the monomers were studied. Based on the optimum conditions, PBS with a weight‐average molecular weight of 2.35 × 104 was obtained in a short time of 20 min.Synthesis of poly(butylene succinate) under microwave irradiation.magnified imageSynthesis of poly(butylene succinate) under microwave irradiation.

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α-MnO2/h-MoO3 hybrid metal oxide materials with different weight ratios were successfully synthesized. The prepared nanocomposite material has been demonstrated to be an electrode material for potential application in electrochemical charge storage devices as well as an efficient photocatalyst for dye degradation. The results showed high ionic conductivity, better charge transfer ability, viability for high current density, and enhanced specific capacitance (Sc) with appreciable cyclic stability. Electrochemical performances of the prepared materials were investigated by cyclic voltammetry (CV) analysis, galvanostatic charge–discharge (CD) techniques, and electrochemical impedance spectroscopy (EIS). We were able to achieve a maximum Sc value of 412 F/g and 358 F/g at a current density of 1 A/g for the composite with 25% h-MoO3 mass loading from a three electrode cell and two electrode symmetric cell configuration, respectively, and it could deliver an outstanding energy density of 50 Wh kg–1 with a power density of 1 KW kg–1, which is a very appreciable result compared to bare metal oxide electrode materials. In addition, 94% of methylene blue (MB) degradation was observed for the prepared composite material under visible light irradiation. The possible photocatalytic mechanism is schematically illustrated.