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Herein, the Co3O4/NiO nanocomposite has been synthesized as a catalyst for thermal degradation and photodegradation of the malachite green dye. Its morphology showed small spherical particles with an average particle size of 52.82 ± 17.73 nm. The XRD pattern and XPS analysis proved the formation of Co3O4/NiO nanocomposite with the growth of both Co3O4 and NiO at crystal contents proportions of 67.7 ± 17% and 32.3 ± 16%, respectively. The TGA results indicated that the Co3O4/NiO nanocomposite is nearly thermally stable up to 1000 °C. The synthesized Co3O4/NiO nanocomposite recorded an optical energy band gap of 4.27 eV and a surface area of 27.4933 m2/g. Besides, its photocatalytic activity was compared with the photolysis and thermocatalytic activity. The velocity constant (kapp) value for photocatalysis was higher than that for photolysis by ten folds. Besides, various effects like dye concentration, pH, catalyst amount, and different scavengers were also evaluated. [ABSTRACT FROM AUTHOR]

Active pharmaceutical ingredients (APIs), despite their beneficial effects on human or animal health, have emerged as an environmental unwanted material due to their excessive use and subsequent release into the aquatic environment causing deleterious effects in organisms. Effective strategies for the removal of APIs are therefore the need of the day as the existing strategies are not efficient. The application of photochemical treatments, namely heterogeneous photocatalysis for the removal of the APIs in water is one of the effective methods. In this respect, we have prepared manganese oxide/cobalt oxide photocatalyst which has emerged as effective treatment methodology for pharmaceutical removal. The photocatalyst was prepared though sol–gel method and then characterized using field emission scanning electron microscopy, X-ray diffraction, Brunner–Emmitt–Teller analysis, thermogravimetric analysis and diffuse reflectance spectroscopy. The photocatalyst was used to degrade the antibiotic (ciprofloxacin). Both photolysis of antibiotic without any catalyst under sun light and photocatalysis in the presence of catalyst were studied and compared. Catalysis was performed under different experimental conditions such as pH, antibiotic concentration, and catalyst dosage and were optimized. The photocatalysis (k = 7.9 × 10−2 min−1) was found to greater than the photolysis (k = 3.8 × 10−3 min−1) indicating the catalytic activity of the prepared photocatalyst. [ABSTRACT FROM AUTHOR]

Combating pathological conditions related to hyperactivity of enzymes remains a formidable challenge for health. Small molecules therapy constitutes one of the means to circumvent the medical disorders resulting from enzyme hyperactivity. In this regard, we have synthesized structurally diverse amino acid hybrid Schiff bases (5a–5l and 10a–10k) and evaluated them for carbonic anhydrase II, α-glucosidase, and urease inhibitory potential. These new chemical scaffolds showed variable efficacies against the selected enzymes. The results indicated that compounds 5b (11.8 ± 1.33 µM), 10i (83.3 ± 1.13 µM), and 10f (88.2 ± 2.27 µM) are the most active scaffolds against carbonic anhydrase II, α-glucosidase, and urease, respectively. A structure–activity relationship revealed the most structural features contributing to the overall activities. Molecular docking suggested that these compounds possess excellent binding interactions with the active site residues of the targets by interacting through hydrogen bonding, π–π, and π–cation interactions. [ABSTRACT FROM AUTHOR]

A series of iron-based nanocomposites such as Cu–Fe (CFNCs), Ni–Fe (NFNCs), Ag–Fe (SFNCs) and Al–Fe (AFNCs) were fabricated via sol–gel route. An extensive investigation about crystallinity, microstructure, electrical and optical properties was carried out by utilizing X-ray diffractometer (XRD), diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) and scanning electron microscopy (SEM). The frequency-dependent AC conductivity, dielectric constant and dielectric loss were measured in the frequency range of 25 kHz–2 MHz at room temperature via an LCR meter. The highest conductivity ~ 2.85 × 10−7S/m was revealed by AFNCs as compared to other nanocomposites. The Maxwell–Wagner model for induced polarization and Koop's phenomenological theory of dielectrics were followed by all the fabricated nanocomposites in the temperature range of 30–600 °C. The maximum dielectric constant ~ 930 was measured for AFNCs at a temperature of 200 °C. Furthermore, the synthesized nanocomposites effectively degraded a toxic organic dye Rhodamine B (RhB) and the degradation (%) ~ 77, 85, 86, and 87 within the time of 50, 40, 50 and 70 min was recorded for CFNCs, NFNCs, SFNCs and AFNCs, respectively. [ABSTRACT FROM AUTHOR]

This study involves the preparation and utilization of Al-based catalysts for the photo-catalytic degradation of acridine orange (AO) dye. Al–Sr and Al–Cd were developed in metal oxides nanoparticles and layered double hydroxides (LDH) morphology respectively. The LDH nature of Al–Cd catalyst was confirmed via X-ray diffraction (XRD) spectrum with the characteristic peak at 2θ =11.8º. Sheet like morphology was adopted by both the catalysts as analyzed through field emission scanning electron microscope. The Al–Cd-LDH sheets were assembled above each other. The crystal phase and functional groups of the catalysts were studied through XRD and Fourier transformed infrared spectroscopy respectively. The thermo gravimetric analysis showed the greater stability for Al–Cd-LDH as compared to Al–Sr metal oxides. A band gap of 2.85 eV and 2.6 eV was calculated for Al–Sr metal oxides and Al–Cd-LDH respectively by utilizing diffuse reflectance spectroscopy. The Nitrogen adsorption/desorption isotherms indicated 62.83 m2/g surface area for Al–Cd-LDH and 24.63 m2/g for Al–Sr metal oxides. Similarly, the total pore volume and average pore sizes were 0.933 mL/g and 0.9685 nm for Al–Cd-LDH and 0.0437 mL/g and 1.0393 nm for Al–Sr metal oxides. Both catalysts showed prominent and effective results for the degradation of AO dye. Under UV–Vis light irradiation, the Al–Sr metal oxides showed approximately 90% degradation in 90 min, while Al–Cd-LDH showed less than 50% efficiency. However, with the increase of irradiation time, the degradation rate of Al–Cd-LDH was enhanced to approximately 90% after 240 min. The Al–Cd-LDH showed 29% of acridine orange dye adsorption after 240 min while Al–Sr metal oxides showed 26% adsorption after 90 min. The low catalytic performance of Al–Cd-LDH could be attributed towards the LDH nature which probably interfered the electronic moments for free radical formation. Furthermore, the effect of various parameters such as dye concentration, pH, catalyst amount and different scavengers were also evaluated. Both catalysts showed good recyclability and hence better stability. [ABSTRACT FROM AUTHOR]