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β-Bi 2 O 3 and Ni-incorporated β-Bi 2 O 3 nanoparticles with different Ni incorporating amounts (0, 2, and 4 at. wt. %) were successfully synthesized through a viable hydrothermal process. As-synthesized nanoparticles were analyzed by complementary analytical tools such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), UV–visible spectroscopy (UV–Vis), and photoluminescence spectroscopy (PL) for structural, microstructural, compositional, and spectral properties. The photocatalytic performance of synthesized nanoparticles was assessed by subjecting them to visible light irradiation and monitoring the decomposition of rhodamine-B dye. The findings demonstrated that the inclusion of Ni(4%) in β-Bi 2 O 3 nanoparticles significantly enhanced its photocatalytic activity compared to pristine β-Bi 2 O 3 which is desirable for environmental remediation. This improvement may be caused by increased generation of electron-hole (e−-h+) pairs, reduced recombination rate of these pairs, enhanced absorption of visible light, and a decreased band gap energy. To evaluate the specific capacitance characteristics of synthesized electrode materials, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance analyses were conducted. The super capacitance activities of prepared electrode materials were observed in the order of Bi 2 O 3 < Ni(2%)-Bi 2 O 3 < Ni(4%)-Bi 2 O 3. Notably, Ni(4%)-Bi 2 O 3 nanocomposite exhibited higher supercapacitance, which can be attributed to the effective role of appropriate nickel incorporation in Bi 2 O 3. These results suggested that the incorporation of Ni(4%) into β-Bi 2 O 3 to form a nanocomposite showed greater capability as an effective electrode material for advanced energy storage devices, especially supercapacitors. Ni (0,2,4%) incorporated-Bi 2 O 3 nanoparticles were successfully synthesized and characterized through viable techniques. Ni (4%)- Bi 2 O 3 nanoparticles have shown enhanced visible light driven photocatalytic activity against organic dyes for environmental remediation. It also exhibited high supercapacitance desirable for high capacity electrode material employable in supercapacitors. [Display omitted] • Ag NPs-loaded brookite TiO 2 NWs supported on rGO sheets were produced hydrothermally. • Structure and morphology were evaluated by XRD, XPS and SEM/TEM. • Ag–TiO 2 /rGO nanohybrid exhibited an excellent light induced photocatalytic performance. • A suitable schematic mechanism was proposed for photocatalytic degradation of dye. • Ag–TiO 2 /rGO nanohybrid demonstrated fairly high electrochemical electrode material characteristics. [ABSTRACT FROM AUTHOR]

Dissimilar material (Al and steel) tubes have been successfully joined together using magnetic pulse welding technique by setting optimized parameters i.e., discharge voltage and standoff distance. The welded interface has revealed an irregular wavy morphology with melt pockets (max. width ∼20 μm) consisting of intermetallic compound embedded in elemental mixture. High resolution electron microscopy and compositional analysis through energy dispersive x-ray spectroscopy (EDXS) have revealed the formation of 2–3 μm long rod-shaped Fe-Al intermetallic compound. Non-destructive ultrasonic C-scans of the sample welded at 15.5 kV discharge voltage and 1.25 mm air gap have indicated sound welds between the two materials depicting 80% joint integrity while considering the backwall reflection threshold at 50%. The corrosion behaviour at the weld interfaces has been investigated in aqueous solution of 3.5 wt. % NaCl using both potentiodynamic and immersion tests revealing the influence of the intermetallic compound layer on corrosion. [Display omitted] • Non-destructive ultrasonic C-Scan characterization of magnetic pulse welded Al-Steel tubes. • Weld interface consists of 10–20 μm thick melt pockets of Al-Fe intermetallic. • The IMC layer thickness at the interface is directly proportional to the heat input that accelerates the corrosion rate. [ABSTRACT FROM AUTHOR]

An aquatic plant, water hyacinth was used after modification with poly-aniline (PANI@WH) as an adsorbent for removal of Cr (VI) from aqueous solution. The effect of pH, time, dose and concentration on Cr (VI) removal was investigated following batch adsorption process. The adsorption of Cr (VI) on PANI@WH adsorbent followed Freundlich adsorption isotherm as well as pseudo-second-order kinetic model. Maximum adsorption capacity obtained by isotherm has been achieved as 31.45 mgg−1 at 323K. Adsorption of Cr (VI) proceeds through film diffusion rather than intra-particle diffusion. Thermodynamic studies suggested endothermic and spontaneous nature of adsorption due to positive enthalpy and negative Gibbs free energy values. On the basis of the value of mean free energy, Gibb's free energy of adsorption and activation energy obtained in the present investigation suggested that adsorption of Cr (VI) on polyaniline coated water hyacinth occurs through physical adsorption. Surface characterization studies such as Field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared, Brunauer, Emmett and Teller surface area, X-ray photoelectron spectroscopy, X-ray diffractometer, atomic force microscopy and high resolution transmission electron microscopy illustrated adsorption mechanism of the adsorbent. The predicted % removal of Cr (VI) was obtain by response surface methodology model are compared with the experimental % removal of Cr (VI) obtained by batch adsorption process. Prepared composite adsorbent can be reused for several cycles and it gives 85% Cr (VI) removal efficiency even after 4th cycle which shows its good regeneration ability. [Display omitted] • PANI@WH is low cost adsorbent and offered 98.5% Cr (VI) removal. • Freundlich isotherm is followed by Cr(VI) adsorption on PANI@WH. • Cr (VI) adsorption on Cr(VI) on PANI@WH followed physical adsorption. • The adsorption of Cr(VI) on PANI@WH followed pseudo-second-order kinetic model. • FESEM,EDX, and XPS studies confirmed the adsorption of Cr(VI) on PANI@WH. [ABSTRACT FROM AUTHOR]