Nickel and either tantalum or niobium-codoped TiO2 and SrTiO3 photocatalysts with visible-light response for H2 or O2 evolution from aqueous solutions†
Abstract
TiO2
(band gap = 3.0 eV) and SrTiO3
(band gap = 3.2 eV) codoped with nickel and either tantalum or niobium ions showed photocatalytic activities for O2 evolution from an aqueous silver nitrate solution and H2 evolution from an aqueous methanol solution under visible light irradiation (λ > 420 nm). The visible-light responses were due to the charge-transfer transition from the