Effects of pH on morphosynthesis and photocatalytic activity of calcium titanium oxides via a facile aqueous strategy

By controlling pH values, calcium titanium oxides with various morphologies had been synthesized via a simple hydrothermal route. No surfactants or templates were involved in the shaping process. The results found that pH values had a crucial effect on the crystal phase and shape evolution of the samples. With increasing pH values, the obtained sample changed from one-dimension (1D) CaTi2O5 rod or shuttle-like shape to two-dimension (2D) CaTi2O4(OH)2 nanosheets, and then to three-dimension (3D) CaTiO3 aggregated prisms, butterfly-like dendrites and cross cubic shapes. The formation mechanism was proposed for the evolution of phase and morphology. 3D CaTiO3 butterfly-like sample showed good photocatalytic activity due to unique morphology, enhanced light harvesting and large surface area.