Study on Synthesis and Characterization of Cu-Ni Doped TiO<sub>2</sub> by Sol-Gel Hydrothermal

Abstract

Titania (TiO 2 ) as a semiconductor has been intensively studied during the last decades. Regardless of its superior photocatalytic performance and extensive environmental applications, it has a wide bandgap which lead to a photocatalytic activity only in ultraviolet (UV) irradiation. To shift the activity of TiO 2 to visible region, a series of monometallic and bimetallic doped TiO 2 was prepared with 10wt% total metals loading. The photocatalysts were synthesized by sol-gel associated via hydrothermal method. The properties of the photocatalysts such as crystal size, surface morphology, total surface area, chemical state of the elements, and bandgap were investigated by using thermogravimetric analysis (TGA), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and BrunauerEmmettTeller (BET) measurement. XRD analysis showed that all samples displayed anatase (101) as a main phase of TiO 2 with average crystal size between 10-16 nm in a good agreement with the TEM results. The FESEM images show spherical particles less than 20 nm in size. The BET results indicated that all samples are mesoporous. The band gap of Ni-Cu/TiO 2 is reduced to 2.65 eV with more absorbance in the visible region compared to those of cu/TiO 2 and Ni/TiO 2 .