In this study, six sol‐gel copper/magnesium substituted derivatives of 58S‐BG, that is, a mol% series of 60SiO2–4P2O5–5CuO–(31–x) CaO/xMgO (where x = 0, 1, 3, 5, 8, and 10), were synthesized as new multifunctional bioactive glasses (BGs). Afterwards, the effect of MgO/CaO substitution on the in vitro formation of nanohydroxyapatite (HA), osteoblast‐like cell responses, and bioactive glasses antibacterial performance were studied. X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) results revealed that Cu‐substituted 58S‐BG consisting of 5 mol% MgO (BG‐5/5) had capability of the formation of HA on its surface while, Cu‐substituted 58S‐BGs consisting 8 mol% and 10 mol% MgO (BG‐5/8 and BG‐5/10) displayed lower bioactivity. The In vitro investigations proved that the highest values of both differentiation and proliferation of MC3T3‐E1 cells can be obtained from a 5 mol% MgO substituted BG. Furthermore, these novel Cu/Mg‐substituted 58S‐BGs displayed antibacterial effect against methicillin‐resistant staphylococcus aureus bacteria. Taken together, the results suggest the equally substituted BG‐5/5 (ie., the one consists of 5 mol% of both CuO and MgO) as a promising candidate for bone tissue engineering, among all newly designed BGs in this work, owing to its desirable cell proliferation, ALP activity, and antibacterial properties.

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This study aimed to evaluate the corrosion properties of different samples coated by the laser-cladding method to find the optimal laser parameters. Thereby, potentiodynamic polarization (Tafel) and electrochemical impedance tests were performed to assess the corrosion resistance of coated samples. Consequently, the corrosion morphology of tested samples was inspected by scanning electron microscopy. The results demonstrated that the laser power directly correlates with pitting corrosion and defects on the surface of the samples. Moreover, when molybdenum and chromium ions are increased in the electrolyte solution, the passive and protective layers are more durable, as the ions are sited within the holes and defects, reducing the surface corrosion rate.

In this study, the electrocatalytic activity of nickel foam, which is activated by cobalt, molybdenum, and nickel phosphide nanostructures, is prepared by the plasma hydrothermal method for use in the release of hydrogen and oxygen. The morphology and crystallographic structure of the synthesized phosphide specimens were examined by means of scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction. Moreover, the electrolysis activity for these sets of specimens was investigated using the Tafel polarization curve or linear sweep voltammetry, cyclic voltammetry, as well as by means of the electrochemical impedance spectroscopy technique. Preliminary results show that nickel phosphide presents the highest electrocatalytic activity than the other phosphides developed in this research. In this regard, it presents an electrocatalytic activity to release hydrogen and oxygen of around −1.7 and 0.82 mV, which is measured at a current density of 100 mA·cm−2, respectively.

In this research, copper-tin alloy nanoparticles were made by a mechanical alloying method and were examined by two well-known and common bactericidal tests, optical density, and colony-forming units count in terms of bactericidal properties. To confirm the results, two different percentages were used as Sn-50Cu and Sn-83Cu, and standard amounts of these alloys were added to the Escherichia coli bacterial culture medium. The results of optical density show that with the addition of more values to the culture medium for bacteria, witnessing the destruction of bacteria, and also the results of colony counting tests can be seen that the number of colonies has decreased over time, even close to zero, which means the environment is free of bacteria. These standard values were different for both alloys; for the Sn-50Cu alloy, the maximum value was 4.5 mg, and for the Sn-83Cu alloy, it was 2.75 mg, which did not make any difference with the addition of these nanoparticles to the bacterial culture medium.