Fig. 4. Photocatalytic H₂ evolution and photoexcited charge dynamics of Pt-modified BaTaO₂N photocatalysts.

a Photocatalytic performance of H₂ evolution on different Pt-modified BaTaO₂N photocatalysts from an aqueous methanol solution. Conditions: Pt-modified BaTaO₂N photocatalyst, 0.1 g; cocatalyst, 0.3 wt% in total (sequential decoration method: 0.1 wt% by impregnation–reduction and 0.2 wt% by photodeposition); 10 vol% aqueous methanol solution, 150 mL; light source, 300 W Xenon lamp equipped with a cut-off filter (λ ≥ 420 nm); reaction system, Pyrex top-illuminated vessel connected to the closed gas-circulation system without evacuation of gas products. b, c Transient absorption decays corresponding to electron dynamics (b) and hole dynamics (c) in different Pt-modified BaTaO₂N photocatalysts probed at 11000 cm⁻¹ (910 nm, 1.36 eV) and 15400 cm⁻¹ (649 nm, 1.91 eV), respectively.