The effects of calcination on sol–gel synthesized Gd2Ti2O7 photocatalyst for degradation of Reactive Brilliant Red X-3B

Tetrabutylammonium hydroxide (TBAOH) was used as a template in the sol to synthesize Gd 2 Ti 2 O 7 . The effects of calcination temperature on the characteristics of the Gd 2 Ti 2 O 7 samples were studied. The crystallite sizes of Gd 2 Ti 2 O 7 prepared at 800, 900 and 1000 °C were calculated to be 33.5, 37.6 and 46.5 nm. The bandgap energies of the Gd 2 Ti 2 O 7 samples were between 3.21 and 3.37 eV when the calcination temperature ranged from 600 to 1000 °C. The Gd 2 Ti 2 O 7 sample obtained at 800 °C had the weakest photoluminescence intensity, i.e., the longest lifetime for the charge carriers. The amorphous samples had large surface area and pore volume but the crystallized Gd 2 Ti 2 O 7 materials had apparently small values. The amorphous materials had very poor activity, and the Gd 2 Ti 2 O 7 sample calcined at 800 °C had the strongest activity on RBR X-3B degradation.