Visible-light-driven photocatalytic behavior of tantalum-oxynitride and nitride

Tantalum oxynitride (TaON) and tantalum nitride (Ta3N5) are investigated in detail as visible-light-responsive photocatalysts. It is found that TaON and Ta3N5 evolve H-2 or O-2 via band-gap excitation in the presence of a sacrificial electron donor or acceptor, respectively. These materials exhibit high stability against photo-corrosion under the reaction conditions for H-2 and O-2 evolution. Structural and physical properties of these photocatalysts were also investigated in detail.