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Polycarbonate (PC)-ZnO films with different percentages of ZnO were prepared by a solution stirring technique and subjected to ultraviolet (UV; λ = 254 nm) irradiation. Structural parameters of the samples and the effects of UV irradiation on the surface properties of the PC and PC-ZnO nanocomposites were evaluated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), water contact angle (WCA) measurements, and a Vickers microhardness (HV) tester. The XRD patterns of the nanocomposite films were found to show an increase in crystallinity with the increasing ZnO nanoparticles percentage. The WCA was found to be reduced from 90° to 17° after 15 h of UV irradiation, which could be ascribed to the oxidation of the surface of the samples during the irradiation and exposure of the ZnO nanoparticles, a result that is also supported by the obtained XPS data. The microhardness value of the PC-ZnO films including 30 wt.% ZnO enhanced considerably after UV radiation, which can also be attributed to the exposition of the ZnO nanoparticles after photodegradation of the PC superficial layer of the nanocomposite films. [ABSTRACT FROM AUTHOR]

In this study, the electrochemical hydrogen storage of bentonite composites containing TiO 2 and Au nanoparticles (NPs) has been investigated by cyclic voltammetry (CV) analysis. TiO 2 NPs were first deposited on the bentonite substrate by reflux technique. Au NPs were then prepared by laser ablation in liquid (LAL) method under different laser irradiation times (6, 12, and 18 min), and utilized in the decoration of bentonite/TiO 2 nanocomposite by physical mixing. X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and elemental mapping were carried out in the characterization of the prepared bentonite/TiO 2 /Au nanocomposite. The surface and chemical properties of the acquired nanocomposite were analyzed by Brunauer-Emmett-Teller and Fourier transform infrared spectroscopy, respectively. Electrochemical measurement was performed on stainless steel mesh prefabricated electrodes in 1 M KOH electrolyte solution. The B-T/Au nanocomposite prepared under 12 min laser irradiation displayed the highest hydrogen storage capacity (15 Cg-1). Image 1 • Au nanoparticles were synthesized by LAL. • Bentonite/TiO 2 /Au nanocomposite was fabricated by physical mixing. • Hydrogen storage capacity was attained 15 Cg-1. [ABSTRACT FROM AUTHOR]

In both developing and industrialized/developed countries, various hazardous/toxic environmental pollutants are entering water bodies from organic and inorganic compounds (heavy metals and specifically dyes). The global population is growing whereas the accessibility of clean, potable and safe drinking water is decreasing, leading to world deterioration in human health and limitation of agricultural and/or economic development. Treatment of water/wastewater (mainly industrial water) via catalytic reduction/degradation of environmental pollutants is extremely critical and is a major concern/issue for public health. Light and/or laser ablation induced photocatalytic processes have attracted much attention during recent years for water treatment due to their good (photo)catalytic efficiencies in the reduction/degradation of organic/inorganic pollutants. Pulsed laser ablation (PLA) is a rather novel catalyst fabrication approach for the generation of nanostructures with special morphologies (nanoparticles (NPs), nanocrystals, nanocomposites, nanowires, etc.) and different compositions (metals, alloys, oxides, core-shell, etc.). Laser ablation in liquid (LAL) is generally considered a quickly growing approach for the synthesis and modification of nanomaterials for practical applications in diverse fields. LAL-synthesized nanomaterials have been identified as attractive nanocatalysts or valuable photocatalysts in (photo)catalytic reduction/degradation reactions. In this review, the laser ablation/irradiation strategies based on LAL are systematically described and the applications of LAL synthesized metal/metal oxide nanocatalysts with highly controlled nanostructures in the degradation/reduction of organic/inorganic water pollutants are highlighted along with their degradation/reduction mechanisms. [Display omitted] [ABSTRACT FROM AUTHOR]

In this research, a simple, green, and efficient approach is described to produce novel bentonite/Ag nanocomposite wherein the preparation of Ag nanoparticles (Ag NPs) deployed the laser ablation method in air; Ag NPs are deposited on the bentonite via the magnetic stirring method. The structural and morphological characterization of the as-prepared bentonite/Ag nanocomposite (denoted as B/Ag30, 30 min being the laser ablation time) is accomplished using different methods. Additionally, the catalytic assessment of the ensued composite exhibited excellent catalytic reduction/degradation activity for common aqueous pollutants namely methyl orange (MO), congo red (CR) and 4-nitrophenol (4-NP) utilizing NaBH 4 as reductant. Furthermore, the recycling tests displayed the high stability/reusability of B/Ag30 nanocomposite for at least 4 runs with retention of catalytic prowess. [Display omitted] • Application of laser ablation in air medium for the synthesis of Ag nanoparticles. • Ag nanoparticles were loaded on the bentonite substrate via the magnetic stirring method. • Bentonite/Ag nanocomposite degrade methyl orange, congo red and 4-nitrophenol in an aqueous medium with NaBH 4. [ABSTRACT FROM AUTHOR]