Search

Building up and an investigating the efficiency of the cost-effective modified graphite for hybrid supercapacitor application is fascinating due to an extraordinary performance of graphite in battery application in day-to-day life about past decades. The metal oxides (Fe, Co, Ni) embedded in graphite was synthesized through the facile ultrasonication-assisted technique. Fe–Co–Ni deposited on graphite (Fe–Co–Ni-G) was studied structurally and morphologically by fourier transform infrared spectroscopy, X-ray diffraction analysis, field emission scanning electron microscopy, and high resolution transmission electron microscopy analyses. The electrochemical studies such as cyclic voltammetry, Galvanostatic charge–discharge analysis, and electrochemical impedance spectroscopy (EIS) analysis were revealed the supercapacitor performance of Fe–Co–Ni-G composite. The superior calculated areal capacitance of Fe–Co–Ni-G was 1355 mF cm−2 at 2 mA cm−2 which was higher than single metal deposited graphite (Fe-G 490 mF cm−2 at 2 mA cm−2) composite. EIS study supported the higher diffusion process of Fe–Co–Ni-G directed to higher supercapacitor performance that is possible for day-to-day life applications. [ABSTRACT FROM AUTHOR]

In the present work, bio-based conductive polymer composites were developed to utilize as supporting material for anode catalysts for oxidation of fuels to generate electrical energy. An in-situ method was adopted to synthesize the conducting polymer carbon composites through combined condensation process by reacting terephthalaldehyde and benzidine, and reinforced with almond shell carbon (BT-ASC). Using formaldehyde reduction method platinum-tin nanoparticles were deposited on BT-ASC composites and were characterized using modern analytical instruments., viz., X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDAX) and Fourier transform infrared spectroscopy (FT-IR). Thermal stability of the conducting polymer composites was analyzed by thermogravimetric analysis (TGA). The electrochemical properties of the prepared catalysts were studied by cyclic voltammetry and chronoamperometric analyses. Data obtained from different studies inferred that the Pt–Sn/BT-ASC catalyst possesses the maximum current density (88.6 mA/mg) with minimum oxidation potential than those of Pt–Sn/ASC, Pt/BT-ASC and Pt/ASC catalysts. The present work ascertains the importance of conducting polymer composites developed using reinforced with bio-carbon towards electro-oxidation of methanol and these supporting materials possess an enhanced catalytic activity than that of reported catalysts. • A bio-based conductive polymer composites as supporting material for anode catalysts. • Pt and Pt–Sn nanoparticles were developed by simple chemical reduction method. • Deducing jf/jb ratio, surface area and catalytic activity relationship of catalysts. • PtSn/BT-ASC, higher surface area and excellent catalytic activity. • PtSn/BT-ASC catalyst material for methanol fuel oxidation in acidic medium. [ABSTRACT FROM AUTHOR]

Microstructural defects play a critical role in flourishing various properties of materials. Here in this article, the effect of Ag substitution on the various properties of CdS quantum dots (QDs) is studied. Ag doped CdS QDs are synthesized using chemical co-precipitation, a simple, cost-effective method suitable for mass-production. High resolution transmission electron microscopy (HRTEM) images show dopant induced change in density and types of microstructural defects. The development of multiple nanotwinning at the cost of stacking faults as well as single twin boundary via the substitution of Ag in CdS lattice is noticed. In present study, a strong quantum confinement is observed and confirmed by the crystallite sizes estimated via X-ray diffraction (XRD) and TEM studies. A systematic enhancement in the bandgap and reduction in crystallite size are observed with increasing concentration of dopant. The atomic concentration of element and chemical bonding in CdS QDs are studied using X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) respectively. Unlike other elemental dopants, QDs when doped with Ag with the varying concentration exhibit a non-systematic emission behaviour with increasing concentration which is correlated to the microstructural defects and confinement strength. [ABSTRACT FROM AUTHOR]

The present study was focused on green synthesis of Silver nanoparticles (AgNPs) using Trigonella foenum‐graceum L. seed extract belonging to specific variety HM (Hisar Mukta) 425, optimizing the different experimental conditions required for the formation and stability of AgNPs. UV‐Vis spectroscopy, Particle Size Analyzer (PSA), Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscopy (HRTEM), X‐ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) were used to characterise the synthesised AgNPs. The average size of AgNPs was found to be 22 nm and were spherical in shape. Additionally, the United States Environmental Protection Agency (USEPA) has listed nitrophenols as a priority pollutant, and biosynthesized AgNPs can catalytically convert them into less harmful aminophenols. One example of a reaction where AgNPs are used as a catalyst is the conversion of p‐nitrophenol to p‐aminophenol, which acts as a bridge for many analgesics and antipyretic medications. Hence, the study is anticipated to have a significant impact on the pharmaceutical, cosmetic, and food industries. [ABSTRACT FROM AUTHOR]

A hydrothermal method was employed for green synthesis of fluorescent carbon dots (GCDs) from Annona squamosa leaves. The synthesized GCDs were confirmed by microscopic and spectroscopic techniques such as: High Resolution Transmission Electron Microscopy (HR-TEM), Atomic Force Microscopy (AFM), UV–Vis spectrometry, Fluorescence spectrometry, X-Photoelectron Spectroscopy (XPS), X-ray Diffraction spectroscopy (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). The produced GCDs had shown multiple properties, including massive antibacterial activity at concentration 200 μg/ml. The stabilization of human red blood cells served as a method to assess the anti-inflammatory activity. We also looked at how GCDs affected the angiogenesis process. The density of blood vessels was significantly decreased after treatment with GCDs, according to the results of the Chorio-Allantoic Membrane assay (p < 0.05). As per the study prepared GCDs from fallen leaves of Annona squamosa have multifunctional applications. [ABSTRACT FROM AUTHOR]

Different concentrations (2 and 4 wt%) of graphite carbon nitride (g-C 3 N 4) was doped into fixed amount of chitosan (CS) and nickel oxide (NiO) nanoparticles (NPs) via a co-precipitation route. The aim of study is to remove the pollutants from wastewater through catalytic activity (CA) and determine the bactericidal activities of synthesized products. X-ray diffraction pattern confirmed the cubic structure of NiO NPs and peak shifted to higher angle upon g-C 3 N 4 doping. Fourier transform infrared spectroscopy revealed the existence of bending and stretching vibration mode. The absorption decreased gradually accompanied blue-shift and assessed bandgap energy increased upon doping. The high resolution transmission electron microscopy micrographs confirmed the formation of cubic-shaped NPs and elongated nanorods were seen for NiO and co-doped NiO. The catalytic efficiency of samples was examined using methylene blue (MB) in the presence of reducing agent. A remarkable dye de-colorization was confirmed with a g-C 3 N 4 and CS doping; moreover, the bactericidal efficacy compared to Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was observed as 3.15 and 13.8 mm, respectively. In silico, molecular docking investigations targeting against b-lactamase S. aureus and FabH E. coli enzymes assisted to elaborate the mechanism underlying microbicidal action of the NPs. [ABSTRACT FROM AUTHOR]

Lanthanum doped magnesium-zinc spinel ferrite samples were synthesized by the simple co-precipitation method with composition M g 0.5 Z n 0.5 F e 2 − x L a x O 4 (x = 0,0.025,0.05,0.075 a n d 0.1). The synthesized ferrite samples were investigated using by powder X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FE-SEM) coupled with energy dispersive spectroscopy (EDS), high resolution transmission electron microscopy (HR-TEM), electron paramagnetic resonance spectroscopy (EPR) and vibrating sample magnetometer (VSM). The effect of the La3+ ion doping on the crystallite size and lattice parameter of the material has been discussed. The crystallite size for all the samples were found to be in the range of 7–12 nm. The percentage porosity and percentage crystallinity of all the samples were found to be in the range of 49–50% and 80–85% respectively. In the frequency region of 400–600 cm−1 two absorption bands attributed to the T d and O h sites of the spinel ferrite have been observed. FTIR band spectra shift from lower to higher region with La3+ ion doping. Agglomeration of the particles is observed in the FE-SEM and HR-TEM images. Additional impurities except carbon are not present in the sample which is confirmed by EDS analysis. EPR analysis shows a decrease in the g-value from 2.18 to 2.12 for the synthesized samples with La3+ ion doping. The resonance field for synthesized sample shifts to higher magnetic field which may be due to ferromagnetic interaction caused by La3+ ion doping. The maximum spin concentration (1.508 × 1021 spin/g) and the relaxation time (4.132 × 10−11 s−1) was observed for the MZL2 composition. Magnetization curve shows the typical superparamagnetic nature of synthesized samples. The calculated squareness value of the synthesized sample refers to the magnetostatic interaction among particles. The obtained coercive field value is low which makes these materials suitable for ferrofluids and hyperthermia treatment applications. [ABSTRACT FROM AUTHOR]

The present study reports a novel technique to synthesise silica nanoparticles through modified sol-gel, ultrasonication, and hydrothermal routes. Physio-chemical and structural characterization was carried out using X-ray diffraction, high resolution scanning electron microscopy, energy dispersive spectroscopy, dynamic light scattering, Fourier transform infrared spectroscopy, ultraviolet-visible, and photoluminescence spectroscopy. The particle size determination revealed the spherical structure of nanoparticles with an average diameter of 85 nm and between 90-170 nm through HRSEM and DLS respectively. Stretching and vibration bands confirming the presence of SiO2 were obtained in FTIR analysis. Spectra from UV-vis and PL spectroscopy were obtained at a maximum wavelength of 233 nm and 555 nm respectively. The anti-microbial effect of SiO2 nanoparticles against E. coli and S. aureus bacteria revealed the appreciable response which renders them for many biomedical applications like drug delivery. The cytotoxicity of SiO2 nanoparticles on human lung epithelial (A549) cell line revealed their non-toxic behavior. [ABSTRACT FROM AUTHOR]

This study explains the synthesis of cobalt‐doped dysprosium oxide nanocubes (Co‐Dy2O3 NCs) and the modification of GCE (glassy carbon electrode), for the selective and sensitive detection of riboflavin (RF). The Co‐Dy2O3 NCs were synthesized by co‐precipitation method and characterized using spectroscopic and microscopic techniques like micro‐Raman Spectroscopy, X‐ray diffraction (XRD), X‐ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FT‐IR), High‐Resolution Transmission Electron Microscopy (HRTEM), Energy‐Dispersive X‐ray Spectroscopy (EDX), and High Resolution Scanning Electron Microscopy (HRSEM). The synthesized Co‐Dy2O3 NCs were coated on the glassy carbon electrode to detect and quantify the concentration of riboflavin in aqueous and real samples. The samples were analyzed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques with three‐electrode system. The modified electrode displays two linear concentration ranges (0.5–50, 50–300 μM) with a low detection limit (LOD) of 0.094 μM and high sensitivity of 3.67 μA μM−1 cm−2. Besides, the fabricated sensor has more selectivity, great reproducibility, repeatability and good stability. Finally, the Co‐Dy2O3 NCs modified GCE based sensor was effectively applied in real sample analysis using milk and egg yolk with good recovery. [ABSTRACT FROM AUTHOR]

Herein, we investigated the effect of the support modification (Sibunit carbon) with diazonium salts of Pd and Pd-Au catalysts on furfural hydrogenation under 5 bars of H2 and 50 °C. To this end, the surface of Sibunit (Cp) was modified with butyl (Cp-Butyl), carboxyl (Cp-COOH) and amino groups (Cp-NH2) using corresponding diazonium salts. The catalysts were synthesized by the sol immobilization method. The catalysts as well as the corresponding supports were characterized by Fourier transform infrared spectroscopy, N2 adsorption-desorption, inductively coupled plasma atomic emission spectroscopy, high resolution transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Hammet indicator method and X-ray photoelectron spectroscopy. The analysis of the results allowed us to determine the crucial influence of surface chemistry on the catalytic behavior of the studied catalysts, especially regarding selectivity. At the same time, the structural, textural, electronic and acid–base properties of the catalysts were practically unaffected. Thus, it can be assumed that the modification of Sibunit with various functional groups leads to changes in the hydrophobic/hydrophilic and/or electrostatic properties of the surface, which influenced the selectivity of the process. [ABSTRACT FROM AUTHOR]

In the current study, iron oxide nanoparticles (IONPs) were synthesized using Ocimum tenuiflorum (OT). The OT leaf extract reduces the ferrous ions to IONPs under microwave irradiation. The biologically synthesized nanoparticles were characterized by Ultraviolet visible (UV–vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Energy Dispersive X-ray (EDX) analysis. High resolution transmission electron microscopy (HRTEM) analysis shows that the IONPs were 9–21 nm in diameter. The zeta potential value of IONPs (+ 15.8 mV) indicate the moderate stability in aqueous medium. IONPs demonstrated excellent photocatalytic reduction and 72% methylene blue degradation was observed in 90 min. IONPs exhibited significant antimicrobial efficacy towards bacterial pathogens at dose dependent manner. The cytocompatibility of IONPs was studied against normal and tumor cells. Comparing toxicity of the IONPs to the A549 lung cancer cells and RAW 264.7 macrophages, higher toxicity was recorded for cancer cells indicating potent anticancer and higher biocompatibility towards normal cells. [Display omitted] • Biosynthesis of iron oxide nanoparticles (IONPs) using Ocimum tenuiflorum extract. • IONPs demonstrated excellent photocatalytic activity towards methylene blue degradation. • IONPs exhibited dose dependent anticancer activity and high biocompatibility towards normal cells. • IONPs demonstrated dose dependent antibacterial activity towards normal cells. [ABSTRACT FROM AUTHOR]

Graphene nanosheets (GNSs)/Al 2 O 3 composites were synthesized by wet milling. In this study, the effects of wet milling speed on the layer distribution, quality and conversion efficiency of graphene in GNSs/Al 2 O 3 composites were studied using scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), raman spectroscopy, fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results show that the intensity of graphite peak decreases and the conversion efficiency of graphene increases with the increase of rotational speed in the range of 200–300 rpm, and a small amount of graphene coated Al 2 O 3 nanoparticles were found in GNSs/Al 2 O 3 composites. The number of layers (≤10 layers) of GNSs gradually increases with the increase of ball milling speed. When the rotational speed is 300 rpm, the graphene conversion efficiency is the highest. At different rotational speeds, graphene defects were the least influential marginal defects. There was no characteristic peak of graphene oxide (GO) appeared in the composite, indicating a small oxidation degree of graphene. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are sought after by many industries including food industries, heavy metal sensing, pharmaceutical, and textile. The present study reports on the biosynthesis of silver nanoparticles (AgNPs) and theirs antibacterial activity using a methanolic leaf extract of Heteropyxis natalensis, a native South African medicinal tree. The synthesised particles were characterised by ultraviolet visible spectroscopy (UV-vis), energy dispersive Xray spectroscopy (EDX), high resolution transmission electron microscopy (HRTEM), and Fourier transform infrared spectroscopy (FTIR). A colour change of the reaction solution from yellow to brown preliminarily confirmed the presence of AgNPs, and a single absorbance peak at 422 nm, using UV-vis spectroscopy, was the indicative of AgNPs. While EDX revealed the presence of elemental silver in the sample, HRTEM identified spherical AgNPs ranging from 5-60 nm. Hydroxyls, alkynes, alkenes, alkanes, esters, and alkyl halides as possible capping agents of silver ions (Ag+) into AgNPs were identified by FTIR. In addition, AgNPs exhibited antibacterial efficacy against 5 strains of pathogenic bacteria: Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis. The results obtained in this study could potentially benefit future research in nanomedical-driven fields. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) endowed with outstanding physico-chemical characteristics expeditiously garnered tremendous popularity in the scientific community. CDs can be synthesized from a variety of natural resources and can replace metal semiconductor quantum dots in the range of applications such as bio-imaging, sensing and catalysis. Herein, CDs are green synthesized from Beta vulgaris via a single step hydrothermal approach (b-CDs). The synthesized carbon dots are characterized using UVâ€"visible spectrophotometry, Fluorescence spectroscopy, High resolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy (FT-IR), x-ray diffraction technique (XRD) and Raman spectroscopy. The b-CDs hence developed exhibited the signature ‘excitation-dependent fluorescence emission’ with its most intense emission in the green region. The quantum yield for the b-CDs obtained by this synthetic approach evinced an appreciable value of 11.6%. The antioxidant property of b-CDs are evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay to obtain a maximum scavenging activity of 94.5% at a concentration of 1000 ÎĽ g mlâˆ'1 and its underlying mechanisms are illustrated. The blood compatibility of b-CDs are assessed using haemolysis assay and the cytotoxicity evaluated using MTT assay shows significant cell growth-inhibition against the human breast cancer (MCF-7) and hepatocellular carcinoma (HepG2) cell lines. This succinct study demonstrates the inherent therapeutic potential of biocompatible carbon dots. [ABSTRACT FROM AUTHOR]

The present work was conducted to biofabricate silver nanoparticles (AgNPs) in single step employing aqueous extract of Dregea volubilis flowers and to investigate its antioxidant, antidiabetic and antibacterial activities. The AgNPs were characterized by UV-Visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX) spectrometry, high resolution transmission electron microscopy (HRTEM) and zeta potential study. The biofabricated AgNPs showed potential antioxidant activity for scavenging DPPH radical (IC50, 40.45 ± 5.06 μg/mL), ABTS radical (IC50, 78.49 ± 1.41 μg/mL), total antioxidant capacity (148.83 ± 2.99 mg GAE/g) along with remarkable inhibitory effects on α-amylase (IC50, 10.62 ± 0.22 μg/mL) and α-glucosidase (IC50, 6.49 ± 0.03 μg/mL). The AgNPs showed notable antibacterial activity in terms of zone of inhibition (in mm) against Pseudomonas aeruginosa (10.67 ± 0.44), Escherichia coli (9.33 ± 0.44), Bacillus subtilis (14.67 ± 0.60) and Staphylococcus aureus (15.67 ± 0.60). [ABSTRACT FROM AUTHOR]

The study of nanocomposites formed by doping of graphene oxide with a metal and polymer is presented in this paper. The graphene oxide contains oxygenated functional groups, like epoxy, hydroxyl and carboxyl, as shown by Fourier transform infrared spectroscopy (FTIR) studies. The existence of these functional groups on the surface of graphene oxide disperses the polymer chain and leads to a good interaction with the metal. The characterization of the prepared nanocomposite was done by X-ray diffraction, energy dispersive X-ray analysis, FTIR, Raman spectroscopy, scanning electron microscopy and high resolution transmission electron microscopy. The results showed that the obtained nanocomposite comprises nano-shaped thin stacked flakes with a well-defined multilayered edge structure. It was also seen that the metal particles were uniformly dispersed on the graphene surface with an average particle size of 1–25 nm. The synthesized nanocomposites can be used for adsorption and degradation of dyes. [ABSTRACT FROM AUTHOR]

In current work, silver nanoparticles (AgNPs) were prepared by a rapid biogenic technique "Green method" utilizing root extract of Olea ferruginea. The synthesized nanoparticles were characterized for UV visible spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning electron microscopy (SEM), High Resolution Transmission Electron Microscopy Studies (HRTEM) and biological assays. UV visible absorption spectroscopy confirms the formation of AgNPs by giving Surface Plasmon Resonance (SPR) peak at 430 nm. FTIR study showed occurrence of various functional groups present in root extract of Olea ferruginea. X-ray diffraction analysis determined the crystalline nature of bio-fabricated silver nanoparticles. The elemental composition of green made silver nanoparticles was studied through Energy Dispersive Spectroscopy (EDS) analysis. SEM & HRTEM study revealed the size, shape, surface morphology & dispersion level of molecules. The biologically synthesized AgNPs showed high antimicrobial, antifungal and antioxidant activity. The AgNPs are observed to be an excellent catalyst on reduction of hazardous dyes, which is confirmed by a decrease in absorbance of maximum values. [ABSTRACT FROM AUTHOR]

[Display omitted] • An ecofriendly and sustainable approach for the synthesis of stable AuNPs. • Aqueous extracts of root and rhizome of Phragmites australis were evaluated. • The spherical shape was the dominant with size (5–20 nm). • Anticancer and antioxidant potentials of AuNPs were confirmed. • Promising application in photocatalytic degradation of MB and MO. In this research, we adopt an ecofriendly and sustainable approach to compare the potentiality and efficiency of Phragmites australis aqueous extracts of two different organs to fabricate gold nanoparticles (AuNPs). The aqueous extracts of plant roots and rhizome were used as alternative reducing agents to conventional chemicals. Various Characterization techniques were used; UV–Vis spectroscopy, Zeta potential, Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Selected Area Electron Diffraction (SAED), Energy Dispersive X-ray Spectroscopy (EDX), High Resolution Transmission Electron Microscopy (HRTEM) equipped with elemental mapping in order to confirm the formation of zero-valent AuNPs, X-ray photoelectron spectroscopy (XPS). Our results demonstrated that both extracts of Phragmites australis are good candidates for the green-synthesis of AuNPs. Zeta potential was used to confirm the stability of AuNPs. The cytotoxic capacities of both AuNPs samples were validated using MTT assay which proved the inhibition of the growth and proliferation of human lung cancer cells (A549 cell line). Antioxidant potentialities were >10%. The phytosynthesized AuNPs exhibited high capacity in removing methylene blue and methyl orange dyes within just one min. This research offers an alternative solution to manage the accumulated unwanted biomass of a widely distributed aquatic macrophyte in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Photocatalytic activity of (CuO-Cu 2 O)Cu/ZnO hetero-junction nanocomposites along with their luminescent, biological applications in the progress of anticancer and antibacterial agents is investigated. The Cu and Zn bi-components modified (CuO-Cu 2 O)Cu/ZnO nanocomposites were synthesized via facile combustion route in the presence of controlled fuel to oxidizer ratio and were characterized by X-Ray Diffraction (XRD) patterns, Transmission electron microscopy (TEM), High resolution Transmission electron microscopy (HRTEM), Scanning Electron Microscopy (SEM), X-ray photoelectron Spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL) and energy dispersive X-ray (EDX) analysis. The PL and UV–Visible diffused reflectance spectral (UV–Vis-DRS) techniques were used to measure the optical sensitivity and tuning of band gap in the samples. The excellent photocatalytic degradation of Methylene Blue and industrial waste water under Sunlight irradiation depends on the mass ratios of Cu/Zn. The findings show that the addition of a certain proportion of CuO, Cu 2 O, ZnO, and Cu can promote efficiency in Sunlight harvesting and separation of charge carriers. Process parameters namely catalyst quantity, dye concentration and a proposal for the mechanism of degradation pathway, experiments for trapping and enhancer are investigated. The study of photoluminescence, CIE and CCT calculations suggests that the present nanocomposite may find applications as phosphor material in warm white LEDs. The second segment of this study deals with the investigation of antibacterial performance of composites upon Gram-negative and Gram-positive bacteria. The results indicate that nanocomposites can be used in antibacterial control systems and as an important growth inhibitor in various microorganisms. The cytotoxic effect of the (CuO-Cu 2 O)Cu/ZnO (CCCZ11) nanocomposite was determined by colorimetric and flow cytometric cell cycle analysis. Our experimental results show that the nanocomposite can induce apoptosis and suppress the proliferation of HeLa cells. The applications of nanocomposites based on Cu, an abundant and inexpensive metal has created much interest in various multifunctional applications. [ABSTRACT FROM AUTHOR]

A promising electrocatalyst containing variable percentage of V 2 O 5 –TiO 2 mixed oxide in graphene oxide support was prepared by embedding the catalyst on Cu substrate through facile electroless Ni–Co–P plating for hydrogen evolution reaction. The solvothermal decomposition method was opted for tuning the crystalline characteristics of prepared material. The optimized mixed oxide was well characterized, active sites centres were identified and explained by X-ray diffraction, high resolution tunnelling electron microscopy, scanning electron microscopy coupled with energy dispersive X-ray and X-ray photon spectroscopy analysis. The structural and electronic characteristics of material was done by fourier transform infrared spectroscopy and the electrochemical behaviour of the prepared material was evaluated by using Tafel plot, electrochemical impedance analysis, linear sweep voltammetry, open circuit analysis and chronoamperometry measurements. The results show the enhanced catalytic activity of Ni–Co–P than pure Ni–P plate, due to synergic effect. Moreover, the prepared mixed oxide incorporated Ni–Co–P plate has a high activity towards HER with low over potential of 101 mV, low Tafel slope of 36 mVdec−1, high exchange current density of 9.90 × 10−2 Acm−2. [Display omitted] • Development of electrocatalysts for HER from transition metal mixed oxides. • Controllable fabrication with remarkable stability and performance assessment. • Favourable rate of HER related to active sites, overpotential and Tafel slopes. • Well illustrated characterization of Ni–Co–P/VTG3 along with all precursors. • Satisfactory electrocatalytic performance assessment via electrochemical analysis. [ABSTRACT FROM AUTHOR]

The present study was reported with synthesize of copper oxide nanoparticles by ethno botanical species. Bio convivial and compatible approaches were made to utilize the renewable source of leaves extract of Achyranthes aspera Linn as efficient capping and stabilizing agent as well. Also, natural A. aspera was functioned as reductant in the formation of CuO NPs. The phytosynthesized CuO nanoparticles were extensively characterized by X-ray diffraction analysis, Fourier transform infrared spectroscopy, Scanning electron microscopy, Energy dispersive X-ray diffraction, High resolution tunnelling electron microscopy and also comprehensively examined their biological applications like antibacterial and antifungal susceptibility against E. lenta, E. aerogenes and C. albicans strains. An XRD result of prepared CuO nanoparticles reveals the monoclinic crystalline structure and average crystallite size of 11–16 nm. The morphology variations for different concentrations of precursor material were noticed by SEM image. Furthermore, the crystalline planes found in SAED pattern of synthesized CuO NPs were coincide to the analysed XRD spectra. In the present study, a novel green approach was used to synthesize of CuO NPs for the antibacterial activity of poorly characterized and emerging pathogens of E. lenta and E. aerogenes. Further, the physicochemical, morphological and biological properties of CuO NPs are discussed. [ABSTRACT FROM AUTHOR]

In the present study, mixed calcium magnesium oxide (CaMgO 2) nanoflakes were synthesized using an ultrasound-assisted co-precipitation method. The physicochemical, structural and functional properties and elemental composition of the nanoflakes had been characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), High-resolution transmission electron microscopy (HR-TEM), Fourier Transform Infrared spectroscopy (FTIR), UV–VIS spectroscopy, X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Moreover, the photocatalytic actions of the nanoflakes were evaluated by the removal rates of methylene blue (MB) and p -nitrophenol (4-NP) under UV irradiation at room temperature. SEM-EDS studies revealed that the nanoflakes consisted of mixed oxide such as magnesium oxide (MgO) and calcium oxide (CaO) particles. The size of the nanoflakes was found to be in the range of 10–30 nm and the average size was 25 nm as confirmed by HR-TEM analysis. XRD revealed that the standard crystal size was calculated to be 25 nm. The synthesized nanoflakes had a strong photocatalytic activity for methylene blue (MB) and p -nitrophenol (4-NP) degradation in the presence of H 2 O 2 under UV light irradiation within 60 min and 30 min, respectively. Hence, the present study proposes that the CaMgO 2 nanoflakes can be employed for the removal of dyes from wastewater. [ABSTRACT FROM AUTHOR]

For environmental reasons, the paints industry shifts from solvent-borne towards water-borne formulations. This change is challenging the business of aluminum pigments, as the hydrogen released by the reaction of aluminum with water degrades the optical properties, besides being a safety concern. In this work, industrial-grade aluminum pigments are encapsulated, by a well-known method, in a silica matrix by sol-gel process using isopropanol - a more suitable solvent for the industry. The effectiveness of the encapsulation process is proven by advanced physical methods (Scanning Electron Microscopy, Energy Dispersive X-Ray Analysis, Selected Area Electron Diffraction, Fourier Transformed InfraRed Spectroscopy, Thermo-Gravimetric Analysis) and by industry-relevant tests (stability in water, hiding power, flop and granulometry). Moreover, advanced surface-applied physical methods (High Resolution Transmission Electron Microscopy combined with Selected Area Electron Diffraction and Scanning Transmission Electron Microscopy, and FT-IR microscopy) clearly show the homogeneity of the resulting pigments, a quality which is highly desirable for practical applications. The results demonstrate that stability comparable to that of pigments passivized by chromium-based inhibitors is easily achieved, for a variety of operating conditions. However, accomplishing a homogeneous silica layer of the right thickness is the determining factor for good optical properties. [ABSTRACT FROM AUTHOR]

This paper deals with adsorption behavior of ruthenium on Tri-n-butyl phosphate functionalized Multi Walled Carbon Nanotubes (MWCNTs-COO-TBP) from aqueous solution. Adsorption method is significant for trace levels (expected level) removal of ruthenium in bioassay (urine) samples which is mandatory requirement of radiation workers in nuclear environment. Multi Walled Carbon Nanotubes (MWCNTs) were initially converted to carboxylated Multi Walled Carbon nanotubes (MWCNTs-COOH) and subsequently treated with Tri-n-butyl phosphate to MWCNTs-COO-TBP. The synthesized MWCNTs-COOH and MWCNTs-COO-TBP were confirmed by Fourier Transform Infrared Spectroscopy (FTIR). Spectroscopic and microscopic techniques such as X-Ray Diffraction (XRD), Raman Spectroscopy, Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDS) and High Resolution Transmission Electron Microscopy (HR-TEM) were used for its characterization before and after adsorption. Various adsorption parameters such as contact time, pH, metal ion concentration and temperature were studied. Langmuir adsorption isotherm model and Pseudo second order kinetics model were found to be best fitted in terms of standard deviation and regression coefficient. Thermodynamics parameters such as enthalpy (ΔH°), entropy (ΔS°), Gibbs energy (ΔG°), activation energy (E a) and sticking probability (SP*) were calculated. The adsorption capacity was calculated and found to be 141.23 mg.g−1.Moreover, quantification of defects, strains with charge doping states were calculated from Raman mapping and correlation plot. [Display omitted] • Synthesis and characterization of Tri-n-Butyl Phosphate functionalized Multi Walled Carbon Nanotubes (MWCNTs-COO-TBP). • Detailed study on adsorption of ruthenium on MWCNTs-COO-TBP and its kinetics, thermodynamics and isotherm. • Functionalization of MWCNTs by TBP and its adsorption for ruthenium, confirmed by FTIR and EDS analysis. • Quantification of defects and strains with charge doping states were calculated from Raman mapping and correlation plot. • The potential application of MWCNTs-COO-TBP for adsorption of Ru from aqueous solution was explored. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiO) nanosheets (NSs) deposited on different amounts (0.025, 0.05, 0.1, and 0.2 wt%) of reduced graphene oxide (rGO) are synthesized through hydrothermal method. The NiO NSs on rGO (rGO-NiO) are characterized by using X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) analyses, and electrochemical analysis. Electrocatalytic activity of rGO-NiO nanocomposite modified glassy carbon (GC/rGO-NiO) electrode is examined towards electrocatalytic oxidation of urea in 0.1 M NaOH using cyclic voltammetry and amperometry techniques. The GC/rGO0.1-NiO nanocomposite modified electrode shows enhanced electrocatalytic oxidation of urea than that of other modified electrodes due to the incorporation of NiO NSs on an optimum amount of rGO. The GC/rGO0.1-NiO modified electrode is used for designing electrochemical sensor for urea, and the detection limit is estimated as 0.47 μM using the amperometry technique. The sensitivity of GC/rGO0.1-NiO modified electrode is found to be 2450 μA mM−1 cm−2. In addition to good electroanalytical performance, the present urea sensor displayed good stability and acceptable anti-interference ability in the presence of 20-fold excess concentration of relevant interferents. The GC/rGO0.1-NiO nanocomposite modified electrode is successfully used for the determination of urea in water sample. [ABSTRACT FROM AUTHOR]

In this work, nitrogen doped carbon dots (NDCDs) and nitrogen doped carbon dots supported palladium nanoparticles composite (n-Pd@NDCDs) were synthesized through hydrothermal carbonization and thermolytic reduction using Morinda citrifolia (M. citrifolia) fruit and palladium chloride as carbon and Pd precursors, respectively. The synthesized materials viz., n-Pd@NDCDs and NDCDs were duly characterized by high resolution transmission electron microscopy (HR-TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The optical properties of NDCDs were studied by ultraviolet visible (UV–Vis), and fluorescence spectroscopy techniques. Further, the electrocatalytic hydrogen evolution reaction (HER) performance of n-Pd@NDCDs was evaluated by linear sweep voltammetry (LSV), Tafel, and electrochemical impedance spectroscopy (EIS) measurements in 0.5 M aqueous H 2 SO 4. The onset potential of n-Pd@NDCDs was about −0.195 V RHE, which was lower than NDCDS (−0.392 V RHE) and bare glassy carbon (−0.603 V RHE). The calculated Tafel slope values of n-Pd@NDCDs were 135 and 141.8 mV/dec, from the voltammetric and EIS methods, respectively. Moreover, the n-Pd@NDCDs exhibited small overpotential of 0.291 V to attain a current density of 10 mA/cm2. The EIS studies revealed that the HER charge transfer resistance was dropped from 84.3 to 18.3 Ω/cm2 while increasing of potential, which revealed good conductivity and electrocatalytic activity of n-Pd@NDCDs. Thus the present work vouched for the candidature of n-Pd@NDCDs as an effective electrocatalyst for the HER in acidic medium. • n-Pd@NDCDs synthesized by reduction of PdCl 2 and carbonization of M.citrifolia. • n-Pd@NDCDs coated GC exhibits good electrocatalytic activity of HER in 0.5 M H 2 SO 4. • The onset potential of n-Pd@NDCDs/GC is about −0.195 V RHE. • Tafel slope of n-Pd@NDCDs (135 mV/dec) is very smaller than NDCDs and bare GC. [ABSTRACT FROM AUTHOR]

Bimetallic Ag and Cu (1:1 wt%) nanoparticles (NPs) were synthesized and annealed at temperatures of 400 °C, 600 °C, and 800 °C using chemical reduction techniques. High temperature annealed (at 800 °C) Ag:Cu sample ratios (5 and 10 wt%) were used to dope MoS2. A wide variety of techniques including X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning, high resolution transmission electron microscopy, differential scanning calorimetry, thermogravimetric analysis, Raman, photoluminescence, and ultraviolet visible spectrophotometry were used to study the morphology, structure, functional groups, excitons recombination, and thermal and optical properties of both annealed and doped samples. The antimicrobial activity of the prepared products was tested on the MRSA-superbug with ciprofloxacin antibiotic as the reference drug. Statistically significant (P < 0.05) inhibition zones (mm) were recorded for the as-synthesized Ag-Cu, heat-treated samples at 400 °C, 600 °C, and 800 °C, doped Ag–Cu/MoS2 5% and Ag–Cu/MoS2 10% which ranged from 6.35–9.85 mm and 8.60–11.75 mm at (0.5, 1.0 mg 50 μl−1) concentrations compared with ciprofloxacin 12.55 mm and DIW 0 mm inhibition zones, respectively. Overall Ag–Cu NPs alone and with different temperature treatments showed less antibacterial efficacy compared with Ag–Cu/MoS2 5% and 10%. Furthermore, molecular docking studies were employed to unveil the binding interaction pattern of NPs in the active pocket of β-lactamase enzyme suggested that it could be a potential inhibitor that could be further evaluated for its enzyme inhibition characteristics. [ABSTRACT FROM AUTHOR]

The dispersion stability of aqueous suspensions containing silicon nitride nanopowder prepared by direct nitridation had been studied. The Si 3 N 4 powder was calcined at 200 °C, 400 °C and 600 °C, respectively. It was aimed to improve dispersion stability of Si 3 N 4 suspension, and the effects were evaluated by measuring the median diameters of the samples taken from the slurries after settling experiments. The relationship between the median diameter and the viscosity of the slurry was discussed on the basis of Stoke's law. High resolution transmission electron microscopy (HRTEM) clearly revealed that the calcined Si 3 N 4 particles were covered by an amorphous surface layer, which was mainly composed of silica. It can also be easily verified according to the results of X-ray photoelectron spectroscopy (XPS) analyses and diffuse reflectance Fourier transform infrared spectroscopy (DRTIFT) measurements. The formation of oxide layer also led to an increase in the total oxygen content of Si 3 N 4 powder. Inductively coupled plasma atomic emission spectrometry (ICP-OES) analyses showed that the soluble impurities decreased after thermal oxide process, which also contributed to the lower of viscosity according to Jones-Dole expression. Electrokinetic behavior of suspensions also indicated that the absolute value of ζ-potential increased after powder calcination. [ABSTRACT FROM AUTHOR]

The increasing demand of rare earth elements in agriculture and industry raises the potential environmental pollution with their inevitable toxicity and biological accumulation. It is necessary to develop an efficient and low-cost technique to effectively remove rare earth elements. N-doped carbon dots (CDs) were green-synthesized using one-pot domestic microwave oven and novel alginate composite (ALG@CDs) beads were fabricated by embedding the N-doped CDs into pure alginate hydrogel beads. The synthetic materials were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, and zeta potential measurement. The ALG@CDs beads could effectively adsorb rare earth elements from aqueous solutions. Taking the adsorption of rare earth element Gd (III) as an example, initial concentration, adsorbent dosage, pH, temperature and contact time were optimized. The adsorption isotherms and kinetics fitted to Langmuir isotherm model (R2 > 0.9991) and pseudo-second-order kinetic model (R2 = 0.9918), respectively. The adsorption capacity of ALG@CDs-3 (201.21 mg/g) for Gd (III) was much higher than that of bare ALG beads (124.38 mg/g) according to the maximum theoretical adsorption capacity of Langmuir model. Competitive adsorption results indicated that ALG@CDs beads had stronger affinity to Gd (III) than to Al (III), Co (II), Ni (II), Zn (II), and Mg (II). The adsorbent could be easily collected and reused for five adsorption-regeneration cycles. The results indicated that the fabricated ALG@CDs beads are the promising materials for adsorption or enrichment of rare earth elements from waste water. [ABSTRACT FROM AUTHOR]

The room temperature polar vapor sensing behavior of a graphene-TiS3 heterojunction material and TiS3 nanoribbons is described. The nanoribbons were synthesized via chemical vapor transport (CVT) and their structure was investigated by scanning electron microscopy, high resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, Raman and Fourier transform infrared spectroscopies. The gas sensing performance was assessed by following the changes in their resistivities. Sensing devices were fabricated with gold contacts and with lithographically patterned graphene (Gr) electrodes in a heterojunction Gr-TiS3-Gr. The gold contacted TiS3 device has a rather linear I-V behavior while the Gr-TiS3-Gr heterojunction forms a contact with a higher Schottky barrier (250 meV). The I-V responses of the sensors were recorded at room temperature at a relative humidity of 55% and for different ethanol vapor concentrations (varying from 2 to 20 ppm). The plots indicate an increase in the resistance of Gr-TiS3-Gr due to adsorption of water and ethanol with a relatively high sensing response (~495% at 2 ppm). The results reveal that stable responses to 2 ppm concentrations of ethanol are achieved at room temperature. The response and recovery times are around 8 s and 72 s, respectively. Weaker responses are obtained for methanol and acetone. [ABSTRACT FROM AUTHOR]

This work describes a new chemiluminescence (CL) system that is composed of lucigenin and carbon dots (CDs). The CDs display absorption peak at 260 nm and fluorescence with a emission peak centered at 524 nm (photo-excited at 470 nm). They were synthesized by hydrothermal treatment of starch and characterized by Fourier transform infrared spectroscopy, high resolution transmission electron microscopy, UV-vis absorption spectra and fluorescence spectra. The effects of oxygen and free radical scavengers on the CL system and on the CL spectra were investigated to elucidate the CL mechanism. It is found that L-cysteine (Cys) enhances the blue CL of the lucigenin-CD system by 59%. The finding was used to design a method for the determination of Cys. CL increases linearly in the 10.0 to 100 μM Cys concentration range, and the detection limit is 8.8 μM (at an S/N ratio of 3). The assay is highly selective over other amino acids. Conceivably, this novel CL system paves the way to numerous new assays based on the use of lucigenin. [ABSTRACT FROM AUTHOR]

The study presents a novel paracetamol (PA) sensor based on Pd nanoparticles (PdNPs) deposited on carboxylated graphene oxide (GO−COOH) and nafion (Nf) modified glassy carbon electrode (GCE). The morphologies of the as prepared composites were characterized using high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and fourier transform infrared spectroscopy (FTIR). The experimental results demonstrated that Nf/GO−COOPd displayed excellent electrocatalytic response to the oxidation PA. The linear range was 0.04–800 μM for PA with limit of detection of 0.012 μM and excellent sensitivity of 232.89 μA mM−1 cm−2. By considering the excellent performance of Nf/GO−COOPd composite such as wider linear range, lower detection, better selectivity, repeatability, reproducibility, and storage stability, the prepared composite, especially GO−COOH support, with satisfactory electrocatalytic properties was a promising material for the modification of electrode material in electrochemical sensor and biosensor field. [ABSTRACT FROM AUTHOR]

A unique brush coating technique was adopted to prepare high microwave absorbing super‐hydrophobic bactericidal fabrics. 3D micro‐CT, field emission scanning electron microscopy (FE‐SEM) and high resolution transmission electron microscopy (HR‐TEM) analyses were employed to establish the composite morphology. X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the embedded silver nanoparticles in the cotton fabrics. The developed thin wearable coated fabrics hold the lowest resistivity of 8 ohm‐cm−2 (lighten up series of LEDs) and electromagnetic interference (EMI) shielding effectiveness (SE) of 30.07 dB at 0.3 mm coating thickness within the X‐band frequency range. These thin coated fabrics can be the used in the flexible electronic devices along with extreme bactericidal feature against E. coli. [ABSTRACT FROM AUTHOR]

In this study, activated carbon (AC) and nano-zerovalent copper (nZVCu) functionalized hydroxyapatite (HA) and alginate beads were synthesized and used for the removal of As3+ from aqueous solution. The characterization by X-ray diffraction, scanning electron microscopy, X-ray energy dispersive spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, high resolution transmission electron microscopy, BET surface area analysis, thermogravimetric analysis, and Fourier transform infrared spectroscopy revealed successful formation of the AC/nZVCu/HA-alginate, nZVCu/HA-alginate, AC/HA-alginate, and HA-alginate beads. The scanning electron microscopy and surface analysis revealed the prepared beads to be highly mesoporous which led to the maximum adsorption of As3+, i.e., 13.97, 29.33, 30.96, and 39.06 mg/g by HA-alginate, AC/HA-alginate, nZVCu/HA-alginate, and AC/nZVCu/HA-alginate beads, respectively. The thermogravimteric analysis showed the nZVCu/HA-alginate beads to be highly stable while the AC composite beads as the least stable to heat treatment. The HA-alginate beads achieved 39% removal of As3+, however, removal efficiency was promoted to 95% by coupling AC and nZVCu with HA-alginate beads at a reaction time of 120 min. The removal of As3+ by the prepared AC & nZVCu coupled HA-alginate beads was promoted with increasing [As3+] 0 and [AC/nZVCu/HA-alginate] 0. The pH of aqueous solution significantly influenced the removal of As3+ by AC/nZVCu/HA-alginate beads and maximum removal was achieved at pH 5.8. Freundlich adsorption isotherm and pseudo-second-order kinetic models were found to best fit the removal of As3+ by the synthesized beads. The high performance of AC/nZVCu/HA-alginate beads in the removal of As3+ even after seven cyclic treatment as well as least leaching of Cu ions into aqueous solution suggest enhanced reusability and stability of HA-alginate beads by coupling with AC and nZVCu. The results suggest that the synthesized beads have good potential for the removal of As3+ from aqueous solutions. Image 1 • Characterization techniques proved nZVCu and AC coupled HA-Alginate beads formation. • Coupling AC and nZVCu enhanced performance and reusability of HA-Alginate beads. • Removal of As3+ best fitted Freundlich isotherm and pseudo-second-order models. • Removal of As3+ was significantly affected by the pH of aqueous solution. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) has been synthesized by modified Hummers' method and characterized by Fourier transform infrared spectroscopy, ultraviolet visible spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, X-ray diffraction technique and Raman spectroscopy. GO characterized using Fourier transform infrared spectra shows that the graphite powder is strongly oxidized by resilient oxidants and the oxygen atoms are present in form of functional groups such as COOH, O–H, C–O–C, and C = O, bonds. GO pellets were prepared to study its dielectric properties as a function of frequency. Dielectric permittivity and electrical conductivity of GO strongly depends upon the extent of temperature. [ABSTRACT FROM AUTHOR]

The alumina-silica nano-sorbent with different alumina-silica ratio were synthesized from thermal power plant fly ash and scrap aluminium foil by alkali extraction, followed by precipitation and calcination. The adsorbent were used successfully for Ni(II) adsorption. The nano-sorbent was characterized by X-ray fluorescence analysis (XRF), X-ray diffraction analysis (XRD), Fourier Transform Infrared spectroscopy (FTIR), Brunauer-Emmet-Teller (BET) analysis, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HR-TEM). In the BET analysis, the proposed nano-sorbent was found to be mesoporous type with a surface area of 136.18 m2/g, which was about 65 times greater than that of fly ash. The adsorption isotherm confirmed a monolayer adsorption and the kinetic result explained that the chemisorption was predominating in presence of external film and intra-particle pore diffusion. The nature of the adsorption process was observed to be spontaneous and endothermic, at low Ni(II) initial concentration by thermodynamic analysis. The optimal values of the process parameters of equilibrium isotherms, namely pH, initial concentration and temperature were determined. The maximum adsorption capacity of proposed alumina-silica adsorbent for Ni(II) was found to be of 49.754 mg/g. Unlabelled Image • Alumina-silica nano-sorbent produced from fly ash. • Nano-sorbent used for removing Ni(II) from waste water. • Optimal operating condition determined through experiments. • Modeling study evaluates adsorption isotherm, kinetics and thermodynamics. [ABSTRACT FROM AUTHOR]

In this research, a novel, biodegradable and environmentally friendly catalyst composed of nickel nanoparticles supported on DNA was prepared and fully characterized by Fourier transform infrared spectroscopy, high resolution transmission electron microscopy, energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy, UV–vis spectroscopy, inductively coupled plasma optical emission spectroscopy, and elemental analysis. The catalyst exhibited remarkable catalytic activity and chemoselectivity for the reduction of various substituted nitroarenes with sodium borohydride (NaBH4) as the source of inexpensive hydride in water at room temperature. High turnover frequency and selectivity were observed for the reduction of all tested substrates. Interestingly, the catalyst could be recovered conveniently for multiple recycling reactions with sustained activity. Furthermore, nearly no nickel species was leached out from the catalyst during the course of reaction, proving the true heterogeneity in the present catalytic protocol. The reduction of various nitroaromatic compounds into their corresponding amines is achieved by DNA supported nickel nanoparticles with the sodium borohydride as the reducing agent in water at room temperature. [ABSTRACT FROM AUTHOR]

• Polyaniline and Tl 2 O 3 -SiO 2 /polyaniline have been successfully synthesized • Polyaniline and Tl 2 O 3 -SiO 2 /polyaniline showed substantial protection performances for C-steel in HCl • The incorporation of Tl 2 O 3 -SiO 2 nanoparticles with polyaniline improve its protection ability • SEM/EDX emphasizes film formation of Tl 2 O 3 -SiO 2 /polyaniline nanocomposite on the steel surface after immersion The current approach discussed a synthesis and characterization of polyaniline (PANI) and two modified loading of 5, 10% Tl 2 O 3 -SiO 2 / PANI, in which Tl 2 O 3 -SiO 2 nanoparticles (NPs) were modified with PANI forming nanocomposites. The composite formation and structure were confirmed by X-ray diffraction (XRD), UV–vis absorption spectra (UV–vis), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), High resolution transmission electron microscopy (HR-TEM), and dynamic light scattering (DLS) technique. The prepared polymer (PANI) and its nanocomposites (Tl 2 O 3 -SiO 2 /PANI) were examined as a corrosion protective layer for carbon steel in 2.0 N HCl at different temperature (30–60 °C) by different electrochemical methods including potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) measurements. PANI inhibited the corrosion of carbon steel, yielding maximum protection capacity of 89%, which were further increased to 96% by the modification with Tl 2 O 3 -SiO 2 nanocomposites. The SEM/EDX investigations confirmed the presence of Tl 2 O 3 -SiO 2 / PANI nanocomposites film covering the metal surface. [ABSTRACT FROM AUTHOR]

• CuWO 4 /rGO nanocomposite was synthesized using sonochemical method and characterized spectral and electrochemical techniques. • The modified CuWO 4 /rGO immobilized GCE shows a high electrocatalytic activity towards the oxidation of nicotine. • Amperometric technique is adopted to identify low detection of nicotine in the presence of cigarette and urine samples. A novel and selective electrochemical sensing of nicotine is studied using copper tungstate decorated reduced graphene oxide nanocomposite (CuWO 4 /rGO) nafion (Nf) immobilized GC electrode (GCE). The CuWO 4 /rGO nanocomposite is synthesized using sonication method and characterized by HR-TEM (High resolution transmission electron microscopy), SEM (Scanning electron microscopy), FT-IR (Fourier transform infrared spectroscopy), SAED (Selected area of electron diffraction pattern), XRD (X-ray diffraction), Raman spectroscopy, Thermo gravimetric analysis (TGA) and EDX (Energy dispersive X-ray diffraction) techniques. The CuWO 4 /rGO/Nf immobilized GCE shows better electrocatalytic response for the detection of nicotine as compared to bare GCE. A better selectivity and sensitivity is achieved using CuWO 4 /rGO/Nf immobilized GCE to detect 0.1 µM nicotine in the presence of 100-fold excess concentrations of different interferents. The present CuWO 4 /rGO/Nf immobilized GCE electrochemical sensor exhibits an ample range of sensing from 0.1 µM to 0.9 µM and the low detection limit is found to be 0.035 µM (S/N = 3). Comparable results are achieved for the determination of nicotine in various real samples such as cigarettes (Gold flake and Wills) and urine samples with improved recoveries. [ABSTRACT FROM AUTHOR]

• The compositions of the films were estimated. • Refractive index for silicon and stoichiometric silicon nitride were found. • The blue shift of the PL peak to the higher energies was observed. • The silicon nanoparticle size ranges from about 0.7–1.0 nm. Plasma enhanced chemical vapor deposition (PECVD) technique was used to deposit silicon nitride (SiN x) thin films. The silane (SiH 4) and ammonia (NH 3) were used as reactant gases. Both the flow rates of the NH 3 and SiH 4 gases were changed but total flow rate kept constant to obtain the different ratio nitrogen (N) in the SiN x films. Fourier transform infrared spectroscopy (FTIR) was used to get information about absorption ratios of the films and the bond types in the films. The refractive index of the films was obtained from ellipsometry measurements. From FTIR measurements and ellipsometry measurements, refractive index for amorphous silicon (Si) and refractive index for stoichiometric SiN x were found as 3.27 and 1.91, respectively. The photoluminescence (PL) measurements were used to see the luminescent of the amorphous Si nanoparticles which were occurred spontaneously during deposition process. High resolution transmission electron microscopy (HRTEM) was used to analyze the Si nanoparticle size. [ABSTRACT FROM AUTHOR]

• New covalent bonding methods of Dawson phosphotungstic acid (P 2 W 17) onto graphene oxide (GO). • Photocatalytic mechanism of GO/P 2 W 17 was revealed. • Covalent bonding of P 2 W 17 onto GO enhances fastness and photocatalytic activity. In this study, single lacunary Dawson type tungstophosphate (P 2 W 17) was modified with γ-(2,3-epoxypropoxy)propyltrimethoxysilane (EPO) to prepare P 2 W 17 -EPO containing epoxy groups, and graphene oxide (GO) was modified with 3-aminopropyltrimethoxysilane to prepare GO-NH 2 containing amino groups. Then, P 2 W 17 was covalently bonded onto the surface of GO through the reaction of P 2 W 17 -EPO with GO-NH 2 for the preparation of GO/P 2 W 17 composite photocatalysts, and their compositions and structures were characterized by the Fourier transform infrared spectroscopy, thermogravimetric analysis, X-Ray diffraction spectroscopy, X-ray photoelectron spectroscopy, high resolution transmission electron microscopy, electrochemical impedance spectroscopy and BET analysis. The photocatalytic activity of GO/P 2 W 17 for methylene blue (MB) was also investigated. The results show that the covalent bonding of P 2 W 17 to GO results in an increase in the specific surface area, a reduction in the charge transfer impedance, and an increase in the transfer of photoinduced electrons. GO/P 2 W 17 can effectively degrade MB in water under UV light and its photocatalytic activity is significantly higher than that of EPO-P 2 W 17 , which can be attributed to the synergetic effects of adsorption and photocatalytic degradation. GO speeds up the separation of photoexcited electron hole pairs of P 2 W 17 during photocatalytic process. Besides, GO/P 2 W 17 also has good reusability and its reuse for 6 times results in only a slight decrease in the degradation rate of MB. It is concluded that the covalent bonding of P 2 W 17 onto GO can improve the photocatalytic activity of P 2 W 17. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cobalt (Co2+) –doped SnO 2 nanoparticles (NPs) used to degrade organic dyes. • Co-doped SnO 2 NPs showed 90% of degradation is achieved for brilliant green (BG) dye within 120 min in the presence of sunlight. • Positive impact of Co2+ on the conductive and electrochemical performance of SnO 2. • Excellent anodic material for supercapacitor applications. Pure and Cobalt (Co)-doped SnO 2 nanoparticles (NPs) were synthesized by a facile hydrothermal method. The SnO 2 NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), Energy dispersive spectra (EDS), High resolution transmission electron microscopy (HRTEM), UV –Visible spectroscopy (UV–Vis), Photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS). The photocatalytic (PC) results of Co-doped SnO 2 NPs showed a higher degradation efficiency than the pure SnO 2 NPs. The electrode made of Co-doped SnO 2 exhibited a maximum specific capacitance (Cs) of 317F/g at the current density of 5A/g. The device gave the retention of 89.95% after 1000 continuous charge /discharge cycles. The experimental results demonstrated that the optimum concentration of Co-doped SnO 2 NPs is an excellent bifunctional material for photocatalytic (PC) and supercapacitor (SC) applications. [ABSTRACT FROM AUTHOR]

• Synthesis of eco-friendly low cost, energy-saving, nontoxic TiO 2 -Al 2 O 3 composites. • Degradation of malachite green and eosin Y dyes. • Removal mechanism trailed by pseudo second order kinetics with R2 =0.963 and ΔH of -54.44 kJ mol−1 indicated the exothermic method. • Achieving 85–90% removal for malachite green and eosin Y dyes in 60 mins. Hazardous containing different groups of dyes from various industries are extremely dangerous and causing unfavorably susceptible dermatitis, skin diseases, transformation, and malignant growth. To overcome the hazards caused by water pollution, eco-friendly composites (TiO 2 -Al 2 O 3) of titanium oxide (TiO 2) and alumina (Al 2 O 3) were synthesized with different proportional ratios (0.25/1, 0.16/1, 0.125/1, and 0.1/1) by kneading method and characterized through X-ray diffraction, scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet-Visible (UV–Vis) spectrophotometry and high resolution transmittance electron microscopy (HR-TEM). Experimental finding showed that the sample TiO 2 / Al 2 O 3 with a molar-ratio of 0.1/1 had the higher photodegradation efficacy for malachite green and from the ratio 0.1/1, the higher photodegradation efficiency was achieved for eosin Y. The comparative studies of TiO 2 -Al 2 O 3 samples were done for basic malachite green and acidic eosin Y and it was estimated that due to adsorbent, Al 2 O 3 surface basicity it showed the highest adsorption for acidic eosin Y and hence had a higher photo degradation removal up to 90% for the eosin Y than for the basic malachite green with 80% photo degradation removal. Reaction mechanism for photodegradation were finest to define by Langmuir isotherms which trailed by pseudo-second order kinetics. The t/q t vs t plots for pseudo-second order kinetic produced high regression coefficients (R2 =0.963), which stated the adsorbate sorption's followed the pseudo second order kinetics. Thermodynamic parameters of dye degradation were calculated by the Van't Hoff equation that indicated the adsorption method was exothermic. The ΔH֯ parameters were found to be -54.44 kJ mol−1. The negative ΔH֯ recommended the exothermic biosorption process. Residuals plots for responses, interaction plots for responses and inter-contour plots were utilized to study the optimum points. Furthermore, accredited to experimental results and a reaction mechanism is planned for the photodegradation of organic dyes with TiO 2 -Al 2 O 3 photocatalyst. Thus the broad band gap of inert semiconductor TiO 2 can be narrower by heterogeneous coupling with Al 2 O 3 through kneading method and showed the excellent photodegradation of organic dyes in the visible region without producing any secondary pollutant. [Display omitted] [ABSTRACT FROM AUTHOR]

Maslinic acid is a naturally occurring dihydroxy, mono-carboxy bioactive triterpenoid. Its bulky structure was the main hindrance in the path of biological activity. Sodium and potassium salts of nano-sized triterpenoid maslinic acid were prepared from maslinic acid and its self-assembly property was studied in aqueous and aqueous-organic binary liquid mixtures. Morphology of the compounds studied by Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), High Resolution Transmission Electron Microscopy (HRTEM), Optical Microscopy, Fourier Transform Infrared Spectroscopy (FTIR) and X-ray diffraction (XRD) revealed vesicular morphology of the self-assemblies. Selective cytotoxicity was performed in leukemic (K-562 and KG-1a) and PBMC cells. Among the three self-assemblies (maslinic acid 1 , sodium maslinate 2 and potassium maslinate 3), sodium maslinate 2 showed better antileukemic efficacy. Sodium maslinate 2 induced apoptosis in leukemic cells by elevating ROS levels and disrupting the cellular antioxidant system. From the in-silico studies, it was confirmed that 2 interacted with extrinsic and intrinsic apoptotic proteins of leukemic cells and killed those cells by inducing apoptotic pathways. The compounds 1 , 2 and 3 showed significant antibacterial efficacy against E.coli strain through binding with several periplasmic membrane fusion protein (MFP) and limiting the efflux system leading to arrestation of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

Highlights • Coating CdS QDs with chitosan improve the material biocompability. • Loading sesamol into CdS@CTS. • Improve stability and decrease IC 50 of sesamol for cancer cells treatment. Abstract Natural products continued to be the treasure trove for the discovery of anticancer drugs. The activity of certain natural products significantly increased with the use of novel drug delivery systems (DDS). Aiming to improve the activity of a natural cytotoxic agent; Sesamol, it was loaded onto cadmium sulfide (CdS) quantum dots (QDs) modified chitosan (CTS). The formed complex Sesamol-CdS@CTS was characterized using X-ray diffraction, UV-Vis absorption spectroscopy, thermogravimetric analysis, dynamic light scattering, Zeta-potential, Fourier transform infrared spectroscopy, fluorescence emission, high resolution transmission electron microscopy, and selected area electron diffraction. The concentration effect of Cd2+ and chitosan on the particle size of CdS QDs was investigated. The cytotoxic activity assay showed that Sesamol-CdS@CTS was more effective against cancer cells compared to the drug alone. The results showed that the half maximal inhibitory concentration values (IC 50) of CdS@CTS, Sesamol, and Sesamol-CdS@CTS were 1730 ± 54, 495 ± 16.4, and 117 ± 3.2 μg/mL, respectively. Our results indicated that CdS@CTS exhibited high loading efficiency, and can be used for drug delivery. [ABSTRACT FROM AUTHOR]

To obtain solid-state photoluminescent core–shell-structured carbon dots@silica (C-dots@SiO2) nanocomposites, the C-dots were synthesized by microwave irradiation and were dispersed in SiO2 through sol–gel technique. Then, the excellent fluorescent property with excitation-independent feature and the core–shell structure of C-dots@SiO2 nanocomposites were successfully characterized through the fluorescence spectroscopy, ultraviolet–visible absorption spectroscopy (UV-Vis), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The as-prepared C-dots@SiO2 powder was mixed with reduced iron powder and then applied to latent fingermark detection. The latent fingermarks on several surfaces labeled with C-dots@SiO2 fingermark powders emitted blue fluorescence under 365 nm UV light and exhibited high contrast between the background and the ridges. Additionally, the C-dots@SiO2 fingermark powder as a fluorescent label for enhancing latent fingermarks demonstrated greater advantages as compared to the conventional fluorescent fingermark powder especially for latent fingermark deposited on porous surfaces. The solid-state photoluminescent core–shell-structured carbon dots@silica (C-dots@SiO2) nanocomposites were successfully fabricated by microwave assisting and sol–gel technique. The C-dots@SiO2 nanocomposite fingermark powders clearly indicated well-defined papillary ridges even for sweat pores, and thus have been expected to be an ideal fluorescent label for latent fingermark visualization. [ABSTRACT FROM AUTHOR]

Abstract Here we demonstrate the extension of applicability of high resolution Attenuated Total Reflection Fourier transform infrared μ-mapping (ATR μ-FTIR) to the investigation of the diffusion of a conservation treatment, ammonium oxalate, within painted plasters. The method demonstrates its potentiality in situations where high lateral resolution is required and the compounds are not easily detectable with conventional analytical techniques. It was applied successfully to explore the interaction between ammonium oxalate solutions and the carbonatic matrix at the microscale. The reaction of the carbonatic aggregate particles was assessed as well as the influence of the treatment parameters on the penetration depth. High resolution ATR μ-FTIR represents a new spectroscopy imaging modality expanding the portfolio of chemically specific analytical tools. [ABSTRACT FROM AUTHOR]

Electro chemical performance. [Display omitted] • SnO 2 nanoparticles are synthesized by a simple hydrothermal method. • The crystallite size of prepared SnO 2 nanoparticles are 25 nm. • 74 % of degradation is achieved for brilliant green (BG) dye within 120 min in the presence of sunlight. • The specific capacitance of 183 fg−1 was measured in the pure SnO 2 nanoparticles. • After 1000 charge discharge cycles, 79.79% capacitance retention was observed. Herein, photocatalytic activity of pure SnO 2 nanoparticles (NPs) were investigated using degradation of Alizarin Red S (AR S), Brilliant Green (BG) and Methyl Orange (MO) dyes under direct sunlight irradiation. Additionally, electrochemical performance of SnO 2 NPs were studied. Sodium hydroxide (NaOH) and tin (IV) chloride pentahydrate (SnCl 4 ·5H 2 O) were used to synthesize SnO 2 NPs through a hydrothermal process. The prepared samples were characterized by thermogravimetry/differential thermal analysis (TG-DTA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), high resolution scanning electron microscopy (HR-SEM), high resolution transmission electron microscopy (HR-TEM), ultraviolet–visible diffuse reflectance spectroscopy (UV-DRS), photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS). After 120 min of sunlight exposure the maximum degradation of AR S, BG and MO dyes had reached to 39, 74 and 59 % respectively. It was found that the BG dye exhibited better photocatalytic degradation. Cyclic voltammeter (CV), galvanic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS) were measured to study the electrochemical performance of SnO 2 NPs. The nanostructured SnO 2 electrode revealed a favourable specific capacitance of 183 Fg−1 at a current density of 5 Ag−1. It had an excellent cycling stability of 79.69 % retention over 1000 charging and discharging cycles. [ABSTRACT FROM AUTHOR]

Sunstar rose ZnO nanoflowers morphology was synthesized using the surfactant-assisted reflux technique. The synthesized 3D ZnO nanoflowers were subjected to various characterization techniques (X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV–Vis diffuse reflectance spectroscopy (UV-DRS), Photoluminescence (PL) spectroscopy, Raman spectra, thermogravimetry analysis (TGA), differential thermal analysis (DTA), X-ray photoelectron spectrometer (XPS), N 2 adsorption-desorption isotherms (BET), field emission scanning electron microscopy (FESEM), energy dispersive X-rays analysis (EDAX) and high resolution transmission electron microscopy (HRTEM)). The sunstar rose morphology was achieved under reflux conditions; the heating throughout the material uniformly allowed the nanoflowers to grow along the c-axis due to the temperature, and surfactant also plays a significant role in the shape of the flowers, as confirmed by FESEM and HRTEM analysis. Further, the synthesized 3D ZnO nanoflowers were utilized the photocatalytic activity was investigated for the degradation of hazardous organic dyes like cationic (Methylene blue (MB)) and anionic (Indigo Carmine (IC)) under sunlight. Overall, it was observed that the degradation of MB and IC was found to be 99.5 (50 min) and 98% (60 min), respectively. ZnO nanoflowers are an efficient photocatalyst for MB compared to IC, as MB degrades faster than IC, which takes less time for degradation. Moreover, shown through photocatalytic processes that synthesized ZnO nanoflowers were highly recyclable, suggesting their potential application in environmental remediation. After the fourth cycle, the effective degradation of MB and IC was 78 and 70%, respectively. The radical quenching test shows that ZnO exhibits charge migration, which may account for its high photoactivity. [Display omitted] • Surfactant-assisted reflux was employed to synthesize ZnO sunstar rose nanoflowers morphology for the first time. • Organic dyes like cationic Methylene blue (MB) and anionic Indigo carmine (IC) show effective degradation under sunlight. • The observed degradation of MB and IC was 99.5% (50 min) and 98% (60 min) under the same conditions, respectively. • The photocatalytic degradation efficiency of MB and IC was observed to be 78% and 70% after four cycles. [ABSTRACT FROM AUTHOR]