Pyrochlore-structural Nd 2 Ta 2 O 5 N 2 photocatalyst with an absorption edge of over 600 nm for Z-scheme overall water splitting.

A pyrochlore-structural oxynitride Nd 2 Ta 2 O 5 N 2 with a visible light absorption edge of ca. 620 nm was explored for photocatalytic water splitting. Dual functions of Nd 2 Ta 2 O 5 N 2 were confirmed by proton reduction and water oxidation half-reactions through separately loading Pt or CoO x as a cocatalyst in the presence of the corresponding sacrificial reagent. Finally, the platinum modified sample (Pt/Nd 2 Ta 2 O 5 N 2 ) was prepared and employed as the H 2 -evolving photocatalyst to fabricate an effective photocatalytic Z-scheme overall water splitting together with PtO x /WO 3 as the O 2 -evolving photocatalyst and IO 3 - /I - as shuttle ions under visible light irradiation.