Effects of current density on preparation and performance of Al/α-PbO₂-CeO₂-TiO₂ composites

Al/α-PbO₂-CeO₂-TiO₂ composite electrodes are prepared by electrowinning. The effects of current density on the thickness, hardness, density, morphology, and elemental composition of Al/α-PbO₂-CeO₂-TiO₂ composites are investigated by metallographic microscopy, micro-hardness testing, scanning electron microscopy and energy dispersive analysis of x-rays. Results show that after incorporating nano-TiO₂ and CeO₂, the thickness increases significantly at a current density of less than 4 mA cm^-2. When the current density is 5.5 mA cm^-2, the micro-hardness values of α-PbO₂ and α-PbO₂-CeO₂-TiO₂ reach 540 and 584 Hv, respectively. The current density measures 4-4.5 mA cm^-2, and the minimum coating densities of α-PbO₂ and α-PbO₂-CeO₂-TiO₂ total 6.03 and 7.21 g cm^-3, respectively.