Electrochemical synthesis of Cu-Fe/brass foil alloy and its oxides under the combustion process as a promising photoelectrode for efficient hydrogen evolution in alkaline solutions

Abstract

Copper, iron, and their alloys are electrochemically prepared on brass foil (77%Cu-33% Zn) plate, from different concentrations of aqueous solution (0.05 to 0.25 M ) of CuCl2 and (0.02 to 0.25 M ) FeCl3, respectively, in which three different concentrations solutions are prepared. XRD, XPS, SEM, and cyclic voltammetry techniques were applied to explore the structures, morphologies, and electrochemical (EC) activities of the deposits. Alloy Oxide with the chemical composition of (30Cu-2.5Fe-35Zn-32.5O) has different phases (CuFeO2 and CuFe2O4) are the major and (Cu-Fe, CuO, ZnO, and Fe2O3) are a minor materials prepared under the combustion reaction. Before combustion, there are two different alloy, the first one is Alloy(I) deposited from solution (0.25M CuCl2 + 0.02M FeCl3) with the chemical composition of (80Cu-2Fe-16Zn-2O) and the second one is Alloy(II) deposited from solution (0.05M CuCl2 + 0.25M FeCl3) with the chemical composition of (60Cu-0.25Fe-36.75Cu-3O) both of them have different phases of Cu, CuO, Fe(OH)2, Fe2O3, Cu-Zn, CuFeO2, and Cu-Fe are confirmed by XRD. The intensity of the peaks depends on Cu%. Furthermore, the high purity of the Cu–Fe alloys was confirmed by EDX techniques. The surface of alloys which are prepared from high concentration of FeCl3 is rough and agglomerated compared to the alloys prepared from high concentrations CuCl2. The H2 evolution reactions (HER) in alkaline solution using these alloys were investigated through electrochemical polarization (ECP) measurements and EC impedance spectroscopies (EISs). alloy(I) with 708 mA Cm− 2 at potential 2.04 V has a high rate of hydrogen production. Also alloy oxide is a burned alloy, tested as a photoelectrode material under a solar simulator with 400 mW cm− 2.It given current density under dark and light are 2.54 mA/Cm2 and 33 mA/cm2, respectively.