Highly effective ruthenium-doped mesoporous Ti1−xRuxO2−y crystals for photocatalytic tetracycline degradation

Abstract

TiO₂ nanomaterials are cheap and stable candidates for the photocatalytic degradation of antibiotic residues in water. However, their activity is still limited by insufficient photon absorption and charge extraction. Here, ruthenium-doped mesoporous TiO₂ crystals (Ti_1−xRu_xO_2−y) are prepared by corroding a step-like layered K₂Ti_8−xRu_xO₁₇ precursor. The removal of potassium ions and the reconfiguration of [TiO₆] octahedrons in K₂Ti_8−xRu_xO₁₇ lead to the formation of mesoporous crystals. Meanwhile, the addition of Ru³⁺ can create Ti³⁺ species and oxygen vacancies in situ inside the crystals, extending the photon absorption from the UV to the whole visible region. The mesoporous Ti_0.95Ru_0.05O_2−y crystals show a 98.74% degradation efficiency of tetracycline hydrochloride within 50 min under simulated sunlight (AM 1.5 G 100 mW cm⁻²) illumination. This work offers an effective way for the construction of efficient photocatalysts with high photon absorption and charge extraction simultaneously.