Estimation of surface recombination velocities and bulk carrier lifetime for SrTiO3 using angle-lapped structures

[Display omitted] •We observed carrier lifetimes from the angle-lapped SrTiO3 with the (100), (110) and (111) faces.•We analyzed for dependence of the carrier lifetimes on the thickness of the angle-lapped SrTiO3.•We obtained accurate surface recombination velocities and bulk carrier lifetimes for SrTiO3. Strontium titanate (SrTiO3) is a promising photocatalyst for solar-to-hydrogen conversions. The carrier lifetime τ dominates the energy conversion efficiency in photocatalysts, and the surface recombination velocities Ss have significant effects on τ. To estimate Ss for the (100), (110), and (111) faces of SrTiO3, we employed samples with angle-lapped structures. The microwave photoconductivity decay method was adopted for the measurements, and the thickness dependence of τ was analyzed. Consequently, we obtained a more accurate Ss compared to that obtained in a previous study. We also observed differences in bulk τ among the samples, and this difference reflects the crystalline quality.