Modified sol-gel/hydrothermal method for the synthesis of microsized TiO2 and iron-doped TiO2, its characterization and solar photocatalytic activity for an azo dye degradation

TiO2 and iron-doped TiO2 microsized powder is prepared by sol-gel method combined with hydrothermal treatment as an alternative to obtain high specific area under controlled conditions. Synthesis parameters such as temperature of hydrothermal treatment (125 degrees C-210 degrees C), calcination temperature (500 degrees C-900 degrees C), and calcination time (1 h-9 h) along with operational parameter as solution pH (3, 7 and 9) in the solar photocatalytic reaction are assessed. TiO2 and iron-doped TiO2 micro powders are characterized by XRD studies, FE-SEM, specific area BET and photocatalytic activity by basic orange 2 (BO2) mineralization under solar irradiation. Results showed that ultrafine anatase microspheres are generated by sol-gel/hydrothermal treatment. Iron-doped TiO2, prepared by consecutive steps such as sot-gel/hydrothermal treatment at 200 degrees C, washed with ethanol, followed by calcination at 600 degrees C and dried with a rotary evaporator, showed the highest discoloration and mineralization of BO2. Outstanding performance is observed when compared with commercial TiO2 (Hombikat). (C) 2018 Elsevier B.V. All rights reserved.