Self-assembly of three-dimensional SrTiO3 microscale superstructures and their photonic effect

3D SrTiO3 microscale superstructures (STOMSs) have been prepared via hydrothermal synthesis and multiple (five times) crystallization process. Branches and trunks on STOMSs show perfect corn-like structures, and each side of the trunks could be considered as grating-analogous structures. These well-ordered trunks along with gratings constitute 3D hybrid microstructures that contribute to light diffraction, and the colorful photonic effects of light diffraction are thought to be due to refractive index modulations in three dimensions. The colors of STOMSs can be tuned from yellow to cyan by changing the growth cycle. This special optical performance could broaden the application scope of SrTiO3.