An economic approach to produce iron doped TiO2 nanorods from ilmenite for photocatalytic applications

Highlights: • Fe-doped TiO₂ was made from natural ilmenite ore via a very cost-effective synthetic pathway. • The photocatalytic performance of Fe-doped TiO₂ under simulated solar light was significantly better than pristine TiO₂ • The effect of iron dopant in synthesised Fe-doped TiO₂ and potential photoreaction mechanism were studied. -- Abstract: Titanium dioxide (TiO₂) is one of the most promising photocatalytic materials, but its practical applications are always limited since it could only be excited in the UV range and has low photocatalytic efficiency due to its wide band gap and fast recombination rate. To overcome these problems, transition metals have been used as dopants to improve the photocatalytic performance of titanium dioxide. However, previous investigations have shown that doping by hydrothermal, sol-gel or other synthetic pathways in the catalyst synthesis are difficult to scale-up for mass production. In this work, ilmenite (FeTiO₃), the most abundant titanium mineral, was used as the raw material to produce iron-doped titanium oxide nanorods by an economic acid treatment approach. Compared with commercial titanium oxide nanomaterials, the photocatalytic performance for Rhodamine B (RHB) degradation of as-prepared materials were significantly improved and could be activated by visible light irradiation. The results from characterization also show the band gap and recombination rate are modified by the iron dopant. This work provides a possible method which can significantly reduce the cost for producing iron doped TiO₂ in high yield for photocatalytic applications.