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Metals with high hardness and corrosion resistance are widely used in many industrial applications. The hardness and corrosion resistance can be enhanced by combining the metal with other metals forming alloys. In this study Ni was combined with W to form Ni-W alloy using the electrodeposition method and tributylmethylammonium methyl sulfate (MTBS) is used as an additive to improve the hardness and the corrosion resistance. The hardness and corrosion resistance of Ni-W alloy synthesized using the electrodeposition method without and in the presence of MTBS are examined. The formation of Ni-W alloy was determined by X-Ray Diffraction (XRD), Ni-W alloy's hardness - by microhardness-Vickers and their corrosion resistance using Electrochemical Impedance Spectroscopy (EIS). The crystallite size of synthesized Ni-W alloy without and in the presence of MTBS before heat treatment is 4.7 nm and 3.5 nm, and after heat treatment is 20.4 nm and 24.7 nm, respectively. The hardness of synthesized Ni-W alloy without and in the presence of MTBS before heat treatment is 678 ± 48 HV and 871 ± 105 HV, and after heat treatment it is 1081 ± 41 HV and 1456 ± 136 HV, respectively. EIS measurement results show that Ni-W alloy without MTBS has a bit higher corrosion resistance (Rct = 763 Ω cm²) than Ni-W alloy with MTBS (Rct = 688 Ω cm²). [ABSTRACT FROM AUTHOR]

Dyes used in textile industry contained organic compounds that cause water pollution. Photodegradation is a common method applied for dyes treatment in wastewater. Metal oxides had been widely used as photocatalyst for organic pollutant degradation in water. However, metal oxides exhibit wide band gap and fast charge (hole and electron) recombination time which decrease the photocatalytic activity. Metal-Organic Frameworks (MOFs) has been developed as an alternative photocatalyst that could decrease the recombination time and lower the band gap. Copper and zirconium-based MOFs with 1,4-benzenedicarboxylic (BDC) linker known as CuBDC and UiO-66, respectively, were used as photocatalyst for the degradation of methyl orange (MO). The photocatalytic activity of CuBDC and UiO-66 was investigated by determining the degradation rate of MO under visible and UV light. CuBDC and UiO-66 were successfully synthesized by solvothermal method and characterized by Powder X-Ray Diffraction (PXRD) to identify the phase and UV-Vis Diffuse Reflectance Spectra (UV-vis DRS) to determine the band gap. The degradation percentage of MO with CuBDC under visible and UV light were 3.6 and 3.3 %, respectively, while the degradation percentage of MO with UiO-66 under visible and UV light were 6.6 % and 36.4 % in 40 min reaction. UiO-66 exhibited a better photocatalytic activity than CuBDC for the degradation of MO under visible and UV light. [ABSTRACT FROM AUTHOR]