Effects of calcination temperature on sol-gel synthesis of porous La2Ti2O7 photocatalyst on degradation of Reactive Brilliant Red X3B

The effects of calcination temperature on properties of porous lanthanum titanate using PEG4000 template in a sol-gel route were studied. Photocatalytic degradation of Reactive Brilliant Red X3B on the materials was evaluated. Monoclinic La2Ti2O7 was synthesized in all the samples. The growing up of La2Ti2O7 crystals leads to apparent increases in crystallite size and cell volume with increasing calcination temperature. The Eg values for the samples are 3.38, 3.40, 3.33 3.36 and 3.44 eV when calcination temperature increases from 600 degrees C to 1,000 degrees C. High temperature calcination leads to apparent loss of both specific surface area and pore volume, although the average pore size is nearly unchanged. The decoloration efficiency by adsorption is in close relationship to the surface area of the materials. The sample prepared at 900 degrees C has the maximum photocatalytic activity on degradation of Reactive Brilliant Red X3B in aqueous solution. A continuous loss of degradation efficiency is observed after recycling of the material due to complex reasons.