Virtual Booth

The contamination of water by toxic hexavalent chromium, Cr(VI), is a critical global concern due to its carcinogenic nature. Effective removal at the point of discharge is essential, often achieved by reducing Cr(VI) to the less harmful Cr(III) using photocatalysts. This study synthesized mixed-oxide zirconia-hematite (ZrO2-Fe2O3) nanotube arrays via the anodization of a zirconium-iron alloy foil at 40 V for 20 minutes, followed by annealing at 600 °C. The photocatalytic performance was evaluated against pristine Fe2O3 and ZrO2 nanotubes for the remediation of Cr(VI) under natural sunlight. Results indicated that the ZrO2-Fe2O3 nanotubes achieved 100% removal of a 10 ppm Cr(VI) solution within 1 hour in dark conditions, driven by strong surface adsorption. Furthermore, the catalyst removed 86% of a high-concentration 70 ppm solution within 3 hours. This superior performance is attributed to the synergistic effects of enhanced adsorption capacity and improved electron-hole separation within the mixed-oxide heterostructure, highlighting its potential for industrial wastewater treatment.