Search

Bismuth based metal oxides are regarded as potential candidates for fabricating photoelectrodes due to their cost-effectiveness, high stability, and significant light absorbing capability. Hence, our present study focuses on rendering an extensive evaluation of nano-sized bismuth tungstate (Bi2WO6) as photoanodes for photoelectrochemical water splitting activity. Bismuth tungstate nanoparticles have been prepared by a facile solvothermal route, and their structural, morphological, elemental composition, and optical properties have been characterized by employing powder X-ray diffraction analysis (PXRD), high-resolution scanning electron microscope (HRSEM), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectroscopy (UV-DRS) technique. For Bi2WO6 sample, the onset potential obtained for OER under dark and light conditions are ηdark = 0.83 V and ηlight = 0.71 V vs. Ag/AgCl respectively. The magnitude of photocurrent density at 1.23 V vs. RHE has been measured as 0.17 µA/cm2. From the Mott–Schottky plot, the flat band potential (Efb) for Bi2WO6 photocatalyst has been obtained as − 0.38 V vs. Ag/AgCl. Nanosized Bi2WO6 exhibited low onset potential, good photocatalytic stability, and suitable band edge potentials facilitating them to act as an efficient photoanode under stimulated solar light irradiation. [ABSTRACT FROM AUTHOR]

The general objective of this research was to study the effect of initial concentration of reactants and ultrasonic irradiation power impacts on the nanostructure of copper (II) coordination polymer of {[Cu3(L)(NO3)2(DMF)(H2O)].3(DMF)}n(1) [H4L = N2,N6-bis[(E)-(2-hydroxyphenyl)imino)methyl)pyridine-2,6-dicarboxamide]. Different characterization methods utilized to determine the nanoparticles of compound 1 and thermal gravimetric (TGA) and differential thermal analyses (DTA) give us thermal stability of the nanoparticles. Reducing the concentration of initial reactants together with the increasing power of ultrasound irradiation can lead to obtaining nanoparticles of compound 1 with uniformed morphology and small particle size. Bandgap energy calculation revealed that as particles size decreases, nanoparticles of compound 1 shift to the blue light wavelengths. Thermal decomposition of the nanoparticles of compound 1 at 400 ºC under an air atmosphere led to the synthesis of phase-pure CuO nanoparticles that are characterized by scanning electron microscope (SEM) and X-ray powder diffraction (XRD) analyses. The CuO nanoparticles obtained in this research appear to be highly dispersed with a particle size of around 23 nm. [ABSTRACT FROM AUTHOR]

Pure SnO2 and doped SnO2 nanoparticles with 2 wt.% ruthenium, 2 wt.% vanadium, and 2 wt.% antimony were synthesized via sol–gel and coprecipitation methods. The obtained doped and undoped dried powders after calcination treatment at different temperatures (973–1223 K) were studied. The structural and morphological characterization of the prepared samples was performed by X-ray powder diffraction (XRD), scanning electron microscope (SEM), differential thermal/thermogravimetric analysis (DTA-TG), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectrum (XPS) and particle size distribution analysis. The effect of structural and morphological properties of the highly additive doped elements nanocrystalline SnO2 powders was discussed. The resulting particles were crystalline oxide particles in the nanometric range (8–31 nm). It was found that the amount of additive played important roles in the particle size effect of nanocrystalline SnO2. Particle size distribution of antimony-doped SnO2 are finer and narrower, and that of vanadium-doped, ruthenium-doped, and undoped SnO2 nanocrystallines are comparatively larger and broader in size distribution. [ABSTRACT FROM AUTHOR]

In this study, Copper-Polyaniline nanocomposite (Cu-PAni) has been synthesized by gamma radiolysis as a novel method and was confirmed by different analytical techniques such as Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), X-ray powder diffraction (XRD). The copper nanoparticle completely covered by a layer of polyaniline with different thickness. The particle mean size was determined from XRD by using the Debye-Scherrer's formula and the particle size was found to be 21 nm. The thermal conductivity of the nanofluid has been measured at different nanofluids volume fractions of 0.2%, 0.4%, 0.6%, 0.8% and 1.0%. The effect of nanofluid temperature on the nanofluid properties is measured in the range from 10 °C to 90 °C. The thermal conductivity ratio of the Copper-Polyaniline nanocomposites water nanofluid increases 107% at nanofluid temperature of 10 °C and 159% at 90 °C for a volume fraction of 1.0%. The Cu-PAni nanocomposite is a potential material for thermal conductivity enhancement of water based nanofluid. [ABSTRACT FROM AUTHOR]

The effect of Zn0.95Ni0.05O nanoparticles addition on the superconducting properties of (Cu0.25Tl0.75)Ba2Ca3Cu4O12−δ superconducting phase was studied. Superconducting samples of type (Zn0.95Ni0.05O)x(Cu0.25Tl0.75)Ba2Ca3Cu4O12−δ, x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0 wt%, were prepared via a single step of solid-state reaction technique at 850 °C under ambient pressure. X-ray powder diffraction, scanning electron microscope, and energy dispersive X-ray were used for samples characterization. The superconducting properties were investigated using the electrical resistivity and DC magnetization measurements. The results showed that the addition of nano-Zn0.95Ni0.05O up to x = 0.6 wt% enhanced the phase formation and improved the superconducting transition temperature Tc in contrary for x > 0.6 wt%, Tc was decreased as x increased. Low field magnetization measurement, H = 20 Gauss, was conducted to the samples to determine the magnetic superconducting transition temperature Tc-mag. Both Tc and Tc-mag were found to have the same behavior with increasing x, whereas the values of Tc-mag were slightly lower than that for Tc values. [ABSTRACT FROM AUTHOR]

Fluoride removal from living entities is the foremost task as it is a non-biodegradable and harmful pollutant mostly found in groundwater. Nowadays, the application of nanoparticles as an adsorbent of fluoride is becoming an intense research due to its high surface area. In the present study, zeolitic imidazolate framework-8 (ZIF-8) nanoparticles adsorption behavior and its efficiency in fluoride removal from an aqueous phase were studied. Various structures, sizes and morphologies of nanoparticles were investigated by Fourier-transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscope, transmission electron microscopy, Raman spectroscopy and zeta seizer. By varying process parameters such as contact time, adsorbent dosage, stirring rate, temperature, and pH, batch adsorption was carried out. The optimum conditions for fluoride removal by ZIF-8 nanoparticles were found as contact time 15 min, adsorbent dosage 0.06 g/L, agitation rate 400 rpm, temperature 20 °C, pH 8. Pseudo-second order in kinetic study showcases that the regression coefficient was found to be 0.99. The experimental data of Langmuir isotherm model of adsorption system reveal the adsorption capacity of 90 mg/g which has better adsorption capacity than other adsorbents. The isothermal multistage adsorption was also studied to understand the mechanism of adsorption of ZIF-8 nanoparticles for fluoride removal. The result in the present work gives a promising adsorbent for the fluoride removal. [ABSTRACT FROM AUTHOR]