Perovskite-type La2Ti2O7 nriesoporous photocatalyst

Crystalline particles of mesoporous La2Ti2O7, a perovskite-type material, were prepared by hydrothermal synthesis at 210 degrees C in the presence of structure directing agent. Crystallization and simultaneous sintering occurred in the time course of the hydrothermal treatment, resulting in the improvement in crystallinity with a sacrifice of the decrease in surface area. The photocatalytic property was evaluated by hydrogen evolution from water with methanol sacrificial agent. The increase and the decrease of the material in crystallinity and surface area were responsible for the photocatalytic activity: the activity was improved by crystallization but the concurrent decrease in surface area (increase in size) of crystalline particles was disadvantageous. (C) 2012 Elsevier Inc. All rights reserved.