Electrodeposition of aluminum and aluminum-magnesium alloys at room temperature

Electrodeposition of aluminum from benzene-tetrahydrofuran-AlCl3-LiAlH4 was studied at room temperature. Galvanostatic electrolysis was used to investigate the effect of various parameters on deposit morphology and crystal size, including current density, temperature, molar ratio of benzene/tetrahydrofuran and stirring speed. The deposit microstructure was adjusted by changing the parameters, and the optimum operating conditions were determined. Dense, bright and adherent aluminum coatings were obtained over a wide range of current densities (10-25 mA/cm(2)), molar ratio of benzene and tetrahydrofuran (4:1 to 7:8) and stirring speeds (200-500 r/min). Smaller grain sizes and well-adhered deposits were obtained at lower temperatures. Aluminum-magnesium alloys could potentially be used as hydrogen storage materials. A novel method for Al-Mg deposition was proposed by using pure Mg anodes in the organic solvents system benzene-tetrahydrofuran-AlCl3-LiAlH4. XRD shows that the aluminum-magnesium alloys are mainly Al3Mg2 and Al12Mg17.