The Effect of Alkaline Earth Metal Ion Dopants on Photocatalytic Water Splitting by NaTaO3 Powder

Alkaline earth metal ions (Ca, Sr, and Ba) are doped into a NaTaO3 photocatalyst, yielding fine particles and surface structures with nanometer-scale steps. The formation of the surface nanostep structure depends on the amount of doped Sr and Ba. The photocatalytic water splitting over NaTaO3 is enhanced: NaTaO3 doped with 0.5 and 1.0 mol% of Sr shows high activities for photocatalytic water splitting without loading of a co-catalyst, and the photocatalytic activity is further improved by loading with a NiO co-catalyst.