Present work is focused on synthesis and characterization of super paramagnetic nanoparticles which showed a high adsorption capacity of dyes which are the first contaminant to be recognized in wastewater of different industries such as paper and textiles. One of these dyes is congo red which is an anionic diazo dye with two azo groups. Magnetite (Fe3O4) nanoparticles were prepared successfully by Sol–Gel method by using ferric nitrate (Fe (NO3)39H2O) and ethylene glycol (C2H6O2) as precursors which were annealed at different temperatures. The obtained nanoparticles were characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Vibrating Sample Magnetometer (VSM) and Zeta Potential. The phase structures, particle sizes and morphologies of Fe3O4nanoparticles were determined by XRD and TEM. VSM shows the magnetic properties of nanoparticles. The results indicate that the obtained nanoparticles are single phase and the particle size and coercivity value of Fe3O4nanoparticles increased with the increase in annealing temperatures. Zeta Potential determined the surface charge of nanoparticles and the results show that nanoparticles can adsorb congo red. The adsorption capacity was evaluated using both the Langmuir and Freundlich adsorption isotherm models.

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The effects of process conditions on Fischer–Tropsch Synthesis (FTS) product distributions were studied using a fixed-bed microreactor and a Co–Mn/CNT catalyst. Cobalt and Manganese, supported on Carbon Nanotubes (CNT) catalyst were prepared by a Strong Electrostatic Adsorption (SEA) method. CNT supports were initially acid and thermally treated in order to functionalize support to uptake more Co clusters. Catalyst samples were characterized by Transmitted Electron Microscope (TEM), particle size analyzer, and Thermal Gravimetric Analysis (TGA). TEM images showed catalyst metal particle intake on CNT support with different Co and Mn loading percentage. Performance test of Co–Mn/CNT in Fischer–Tropsch synthesis (FTS) was carried out in a fixed-bed micro-reactor at different pressures (from 1 atm to 25 atm), H2/CO ratio (0.5–2.5), and reduction temperature and duration. The reactor was connected to the online Gas Chromatograph (GC) for product analysis. It was found that the reaction conditions have the dominant effect on product selectivity. Cobalt catalyst supported on acid and thermal pre-treated CNT at optimum reaction condition resulted in CO conversion of 58.7% and C5+ selectivity of 59.1%.

Nanostructure perovskites such as LaMO3 (where M = transition metal such as Mn, Co, Ni, and Fe) have captured attention in materials science fields due to their promising catalytic properties. In this study, the LaCoO3 perovskite nanoparticles were synthesized by a two‐step route via the sol–gel autocombustion method. In this method, lanthanum nitrate and cobalt nitrate were used as metals sources, after dissolving in distilled water. PVP was used as a surfactant, while urea and glycine were applied as fuel. The sol was formed at the stirring stage at 60°C, and then continued to gelation through water evaporation at 90°C, to end up in the autocombustion state. The product of combustion was washed, centrifuged three times, and heat‐treated at 600°C for 2 h. Synthesized nanoparticles were characterized by scanning electron microscopy, X‐ray powder diffraction (XRD), and particle size analyzer. Characterization results show that nanoparticles were synthesized in a narrow size range, below 100 nm, with perovskite structure using sol–gel autocombustion method; these particles were spherical in shape and without visible porosity on the surface. The purity and crystalline size of nanoparticles were studied through XRD analysis indicating that variation in these parameters depends on the fuel and fuel‐to‐oxidizer ratio, as impurities decreased by increasing the fuel ratio, for both glycine and urea. In addition, using glycine is demonstrated to result in better purity as compared with urea as fuel.

Copper oxide nanoparticles have been received attraction due to their unique properties and potential future applications. In present work nanostructure Copper (II) oxide (CuO) spherical nanoparticle synthesized by solution combustion method and the influence of different fuel and condition on the properties of CuO particle was investigated. Crystalline phase and size indicated by applying XRD and particle size distribution studied further using DLS. Scanning electron microscopy (SEM) was used for morphological study and EDAX analysis shows composition of CuO particles. Nanostructure of copper (II) oxide particle studied further by Transmission electron microscopy (TEM) and selected area electron diffraction (SAED) applied for detail study on crystalline structure of particles.

Due to the extraordinary mechanical, thermal, and electrical properties of graphene, graphene oxide (GO), and reduced graphene oxide (rGO), these materials have the potential to become ideal nanofillers in the electrodeposited nanocomposite coatings. This article provides an overview of literature on the improvements of properties associated with graphene, GO, and rGO-reinforced coatings, along with the processing parameters and mechanisms that would lead to these improvements in electrodeposited metal matrix nanocomposite coatings, where those affected the microstructural, mechanical, tribological, and anti-corrosion characteristics of coatings. The challenges associated with the electroplating of nanocomposite coatings are addressed. The results of this survey indicated that adding graphene into the plating bath led to a finer crystalline size in the composite coating due to increasing the potential development of specific crystalline planes and the number of heterogeneous nucleation sites. This consequently caused an improvement in hardness and in tribological properties of the electrodeposited coating. In graphene reinforced metallic composites, the severe adhesive wear mechanism for pure metallic coatings was replaced by abrasive wear and slight adhesive wear, where the formation of a tribolayer at the contact surface increased the wear resistance and decreased friction coefficient. Furthermore, superhydrophobicity and smaller grain size resulted from embedding graphene in the coating. It also provided a smaller cathode/anode surface ratio against localized corrosion, which has been found to be the main anti-corrosion mechanism for graphene/metal coating. Lastly, the study offers a discussion of the areas of research that need further attention to make these high-performance nanocomposite coatings more suitable for industrial applications.

Recently, nanostructure perovskite oxides such as LaMO3 (M=Co, Ni, Fe, . . . ) received attention in academic researches due to its catalytic properties. In this research, the LaCoO3 perovskite nanoparticles have been synthesized by single-step route via the sol-gel auto-combustion method. The precursors used in this method were lanthanum nitrate and cobalt nitrate, as metals sources dissolved in distilled water and also using PVP as a surfactant, Urea and glycine as an oxidizer. The sol formed at stirring stage at 60°C continued by gelation through the water evaporation at 90°C and then auto-combustion occurred. Product of combustion step was washed and centrifuged three times and later calcined at 600°C for 2 h. As synthesized nanoparticles are characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and particle size analyzer (PSA). The characterization results proved the synthesis of nanoparticles below 100 nm with perovskite structure in narrow size distribution by using this method. The purity and size of nanoparticles vary depending on the fuel and fuel to oxidizer ratio.

Environmental pollution such as hexavalent chromium has been extremely released into the environment and significantly increased global concern. Hexavalent chromium has carcinogen and mutagen effect on organisms. In this study magnetite (Fe 3 O 4 ) nanoparticles were successfully synthesized by sol-gel method with the purpose of removing Cr(VI) from waste water. The phase structures, morphologies, particle sizes, chemical composition, and magnetic properties of magnetite nanoparticles have been characterized by X-ray diffraction, scanning electron microscopy, energy -dispersive analysis by X-ray spectrometer and vibrating sample magnetometer. Synthesized magnetite nanoparticles demonstrated high capacity of hexavalent chromium adsorption. The maximum adsorption of Cr(VI) by Fe 3 O 4 nanoparticles occurred at pH 8.2. The adsorption efficiency of Cr(VI) was explained in terms of Freundlich and langmuire equations.