Sri Wahyuni, Sri Kadarwati, M. Alauhdin, Addy Rachmat, Nuril Huda, Eka Siti Rinjani, Ridho Prasetyo
The synthesis of mixed-phase anatase-rutile TiO2 has been carried out to improve its light response and photocatalytic activity. The synthesis of mixed-phase TiO2 was performed through a sol–gel method in an alkaline solution and followed by a hydrothermal process in an autoclave at a temperature of 150◦C for 3 h. A 60 mL of 0.5 M HNO3 then was added into the TiO2 precipitate followed by the addition of various amount (0 mL, 10 mL, and 20 mL) of H2O2 30%. The suspension was homogenized by a sonication for 30 min to obtain an anatase-rutile mixture phase. The resulted mixed-phase TiO2 was further labelled as A0, A1, and A2, respectively. The High-Score analysis showed that the phase composition of TiO2 was 9.4% anatase, 90.6% rutile (A0); 17% anatase, 83% rutile (A1); and 49.6% anatase, 50.4% rutile (A2). The spectra of diffuse-reflectance showed a shift in the band gap energy from 3.17 eV (fully anatase) TiO2 to 2.75-2.86 eV in A0, A1, and A2 mixed-phase TiO2. These results suggested that the photocatalytic activity of A1 and A2 mixed-phase TiO2 would take place in the early visible-light region (ʎ > 400 nm). The photocatalytic examination of the mixed-phase TiO2 under LED and UV irradiation resulted in a decrease in the rhodamine-B (Rh-B) concentration of up to 92%. However, the photocatalytic activity of mixed-phase TiO2 did not outperform that of the fully anatase TiO2, achieving 98% reduction in Rh-B concentration. © 2026, Magister Program of Material Sciences, Graduate School of Sriwijaya University. All rights reserved.
Chemistry Study Programme, the Faculty of Mathematics and Natural Sciences, Universitas Negeri Semarang, Central Java, Semarang, 50229, Indonesia; Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Sriwijaya, South Sumatra, Ogan Ilir, 30662, Indonesia; Departement of Chemical Engineering, Universitas Diponegoro, Central Java, Semarang, 50275, Indonesia
