Author: Misriyani, If’all, Ruslan and A. M. J. Putra

DOI: http://doi.org/10.31788/RJC.2026.1939581

Hexavalent chromium (Cr(VI)) is a toxic pollutant commonly found in metal industry wastewater. This studysynthesized Fe 3+ -doped TiO2 nanowires via a single-step hydrothermal method with varied Ti/Fe ratios to developan efficient, reusable photocatalyst for Cr(VI) removal. Characterization (XRD, SEM, PSA, and UV-Vis DRS) confirmed one-dimensional nanowires (50-100 nm diameter, several µm length) with maintained anatase phase, reduced crystallite size, and narrowed band gap (3.2 to 2.3-2.4 eV), enhancing visible-light absorption. The 6Ti/Fe3+ sample achieved over 90% Cr(VI) reduction within 60 minutes under UV-Vis light, with a rate constant (kapp) of 0.0201 min -1 three times higher than pure TiO2 and retained >80% activity after 120 minutes. Its stabilityover multiple cycles confirms high durability. The enhanced performance results from the synergy of band gap narrowing, Fe 3+ electron-trap effects, and efficient charge transport along nanowires, making Fe 3+ /TiO2 nanowires, especiallyat 6Ti/Fe 3+ , a promising photocatalyst for sustainable Cr(VI) detoxification in industrial wastewater.

Keywords: Fe 3+ doped TiO2 nanowire, photocatalytic Cr(VI) removal, hydrothermal synthesis, reusablephotocatalysts, industrial liquid waste treatment.