2020 Volume 18 Pages 32-37
Orthorhombic-type sodium tantalite (NaTaO3) is one of the most promising photocatalyst for hydrogen generation via water splitting reaction with ultraviolet-irradiation. In this research, we prepared NaTaO3 crystal from KTaO3 substrate via solid-state K+−Na+ alkaline cation substitution. In the transmission electron microscopy (TEM) observation revealed the perovskite-type KTaO3 crystal phase is transformed into the orthorhombic crystal phase via simple heating of KTaO3 substrate with Na2O2. Atomic scale scanning TEM imaging with energy dispersive X-ray spectroscopy (EDS) are supported that this phase transformation clearly based on the topotactic alkaline cation substitution with K+ and Na+ at a common Ta-O basic lattice structure.