Aurivillius compound Bi5Ti3CrO15 as a visible-light-active photocatalyst for hydrogen production from water

Abstract Layered Aurivillius compound Bi5Ti3CrO15 has been synthesized by a hydrothermal method for the application as a photocatalyst to liberate hydrogen from water. Bi5Ti3CrO15 owns a narrow band gap (Eg ∼ 2.46 eV) and shows stable photocatalytic activity under both full range (λ ≥ 250 nm) and visible light illumination (λ ≥ 420 nm). A short hydrothermal reaction time is critical to achieve high photocatalytic activity as defects such as Cr6+ and Bi5+ can be avoided. An AQE as high as 3.66% at 420 nm ± 20 nm has been recorded, warranting promising application in the field of solar energy conversions. DFT calculation reveals the important role of Cr3+cations for visible light sensitivity of Bi5Ti3CrO15.