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.