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Multicomponent hybrid nanostructures exhibit multifunctional properties and synergistic performance which make them attractive materials for environmental applications. We have fabricated magnetic Au@CoFe2O4-ZnO hybrid plasmonic nanostructures using simple wet chemical route combined with photodeposition and studied their photocatalytic performance towards decomposition of synthetic dyes. XRD, FESEM and Raman were used to examine the structure and morphology of the prepared nanostructures and UV–visible spectroscopy was used for photocatalytic measurements. The solar-responsive photocatalytic decomposition of synthetic dyes MB and MO was examined and results displayed the outstanding performance of Au loaded CoFe2O4-ZnO nanostructures over CoFe2O4-ZnO photocatalysts. The prepared Au@CoFe2O4-ZnO hybrid nanostructures with higher Au loading, the sample CU3, effectively decolorized MB dye in only 20 min of sunlight exposure, achieving an apparent rate constant of 0.062 min−1. For MO dye, the sample CU3 achieved 96.6% degradation in 60 min with an apparent rate constant of 0.022 min−1. Mechanistic studies related to radicals responsible for the photodecomposition were discussed and results revealed that ⋅OH radicals and hot holes play major roles in photodecomposition of pollutants. Overall, Au decorated CoFe2O4-ZnO nanostructures prepared using facile photodecomposition route with excellent recyclability and effortless magnetic recovery represent a promising photocatalyst material and is highly suitable photocatalyst for environmental remediation applications. [ABSTRACT FROM AUTHOR]

The work outlines the synthesis of mesoporous tin oxide (m-SnO2) with enhanced Nitrogen Dioxide (NO2) gas sensing performance by making use of Cetyl Trimethyl Ammonium Bromide (CTAB) as the soft template. Powder X-ray Diffraction (PXRD), Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FTIR) spectroscopy and X-ray Photoelectron Spectroscopy have been used to study the structural characteristics of mesoporous tin oxide. The average crystallite size calculated from the XRD technique was found to be 4.8 nm which is in corroboration with TEM analysis (4.9 nm). The FESEM indicated the porous morphology of the prepared sample which was also confirmed by N2 adsorption–desorption isotherms. The surface area and the average pore size of the sample were calculated from Brunauer–Emmett–Teller (BET) studies and Barrett–Joyner–Halenda (BJH) method and were found to be 154.4 m2 g−1 and 3.2 nm, respectively confirming the mesoporosity of the prepared tin oxide. The sensor was prepared by deposition of m-SnO2 thin film on Inter Digited Electrodes (IDE's) of platinum decorated on a glass substrate. 10 parts per million concentration of oxidizing gas NO2 was tested on the fabricated sensor in the temperature range, 30 °C to 160 °C. Upon interacting with the gas, the sensor exhibited a response of 8635 with response time of 1s and recovery time of 165 s at 80 °C. The efficient sensor performance at 80 °C as observed in the present study is at much lower temperature in comparison with those reported earlier. The sensor has further shown good repeatability in terms of response and recovery at 80 °C. The sensor also exhibited good reproducibility and selectivity for NO2 gas. The enhanced sensor response of mesoporous tin oxide sensor is mainly because of large surface area (154.4 m2 g−1), mesoporous structure and small crystallite size (4.8 nm). The present study therefore establishes m-SnO2 as a potential candidate for efficient sensing of NO2 gas. [ABSTRACT FROM AUTHOR]

Spinel ferrite ZnFe2O4 nanostructures have been prepared as sunlight responsive photocatalysts via facile co-precipitation method. The structural, morphological, and optical responses were diligently characterized using XRD, Raman spectroscopy, FESEM, and UV–Vis absorption spectroscopy, respectively. FESEM studies revealed nanoparticles and porous-like nanoparticle aggregates, found to be of cubic spinel ZnFe2O4 from XRD and Raman studies. Crystallite size varied from 5 to 13.6 nm, whereas band gap changed from 1.89 to 1.95 eV with CTAB concentration variation. ZnFe2O4 nanostructures were employed for sunlight-assisted photodegradation of organic pollutants such as MB, MG, and MO dyes in water. The synthesized ZnFe2O4 nanoparticle aggregates with porous-like morphology with crystallite size of 9.2 nm showed superior photocatalytic response and decomposed 80.4% of MB dye in only 40 min. The superiority of the porous-like ZnFe2O4 nanoparticle aggregates was mainly ascribed to its optimal crystallite size, narrower band gap, and improved sunlight utilization efficiency. A plausible mechanism of photocatalytic oxidation of dye supported by scavenger studies has also been proposed. The synthesized ZnFe2O4 nanostructures have easy magnetic recycling property along with excellent photocatalytic capability and hold potential for the treatment of contaminated water. [ABSTRACT FROM AUTHOR]

Plasmonic nanocomposite thin films find exciting applications in environmental remediation and photovoltaics. We report on thermal annealing driven development of morphology, structure and photocatalytic performance of Au–Cu2O–CuO nanocomposite thin film. Nanocomposite thin film coatings of Au–Cu2O–CuO, prepared by radio frequency (RF) magnetron co-sputtering, were annealed at different temperatures. Thermal annealing driven evolution of morphology of Au–Cu2O–CuO nanocomposite was studied by field emission scanning electron microscopy (FESEM), which revealed significant growth in size of nanostructures from 10 nm to 69 nm upon annealing. X-ray diffraction (XRD) together with Raman studies confirmed the nanocomposite nature of Au–Cu2O–CuO film. UV-visible diffuse reflectance spectroscopy (UV-vis-DRS) studies showed band gap variation from 2.44 eV to 1.8 eV upon annealing at 250 °C. Nanocomposite thin film annealed at 250 °C exhibited superior photocatalytic activity for organic pollutants [methylene blue (MB) and methyl orange (MO)] decomposition. The origins of thermal transformation of morphological, optical and photocatalytic behaviour of the Au–Cu2O–CuO nanocomposite coating are discussed. [ABSTRACT FROM AUTHOR]

Background: Ayurvedic Ariṣṭa preparations hold an age-old heritage in the prevention and cure of metabolic disorders and associated complications. Aim: The aim of the study was to study the antidiabetic activity of a self-fermented Ariṣṭa preparation (DB-07) and its potential in preventing or curing diabetes-induced nephropathy in experimental models. Materials and Methods: Rats with Streptozotocin-induced diabetes were used for studying the various dose effects of DB-07 (2.5, 3, and 3.5 ml/kg/day) in preventive and therapeutic treatment schedules. Metformin (500 mg/kg) was used as a standard drug. Fasting blood glucose and biochemical parameters such as blood protein, urea, uric acid, and creatinine were accessed by various biochemical tests. In vitro α-amylase and α-glucosidase inhibition assay and 2-deoxy glucose uptake assay using rat L6 myotubes were studied for determining the antidiabetic mechanism of action. Results: A dose-dependent and statistically significant effect on lowering the fasting blood glucose level was observed in both preventive and therapeutic scheduled treatments. Treatment with DB-07 significantly reversed the altered biochemical parameters and the effects were comparable to metformin-treated rats. DB-07 exhibited concentration-dependent inhibition of both α-amylase and α-glucosidase enzymes with an IC50 values of 10.93 μg/ml and 8.73 μg/ml, respectively. DB-07 also showed glucose uptake potential (ca. 70% activity at 125 μg/ml) in differentiated L6 myotubes. Conclusions: These observations have revealed the antidiabetic and nephroprotective potential of DB-07. DB-07 can be a potential herbal alternative to maintain a healthy blood glucose level and will prove useful in diabetes-associated renal complications. [ABSTRACT FROM AUTHOR]

Nanocomposite thin films of SnO 2 –ZnO were prepared by carbothermal evaporation of mixture of Sn and ZnO without using any catalyst. The nanocomposite thin films were irradiated with 8 MeV Si 3+ ions at room temperature to fluence varying from 1 × 10 14 to 1 × 10 15 ions/cm 2 . Effects of MeV ion irradiation on the structural and optical properties of SnO 2 –ZnO nanocomposites were studied using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy, Photoluminescence spectroscopy (PL) and Raman spectroscopy. XRD studies revealed the presence of Sn, SnO 2 and ZnO nanostructures in the as-deposited films. FESEM studies on the irradiated samples revealed the formation of ZnO nanosheets. A tentative growth mechanism underlying the formation of ZnO nanosheets is proposed. Ion irradiation resulted in a significant enhancement in the UV and defect emissions from ZnO and SnO 2 nanostructures in the nanocomposite. [ABSTRACT FROM AUTHOR]