Effects of Ca/Ti ratio on morphology control and photocatalytic activity of CaTiO3/Ca(OH)2 composite photocatalyst

A calcium titanate/calcium hydroxide (CaTiO3/Ca(OH)(2)) composite photocatalyst with enhanced activity towards the degradation of organic dyes was synthesized by a simple and direct hydrothermal route through controlling the Ca/Ti molar ratio within the reaction slurry. The photocatalytic performances indicated that the sample generated by Ca/Ti = 4 exhibited the highest photocatalytic activity, which was even higher than that of commercial P25. The enhanced performance of this composite photocatalyst was attributed to the hierarchical concave cuboid structure with high crystallization and high specific surface area, which inhibits the recombination of photogenerated electron and hole pairs, as well as to the combination of CaTiO3 and Ca(OH)(2) which provides OH- to form center dot OH with strong oxidizing properties to promote the separation of photogenerated electron and hole pairs. (C) 2020 Elsevier B.V. All rights reserved.