Defects play an important, and in many cases dominant role in the physical and chemical properties of many oxide materials. In this work, we show that the surface Ti3+ defects in SrTiO3 (STO), characterized by electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS), directly impact the photocatalytic activity of STO. O2 species are found to absorb preferentially on Ti3+ defect sites. Hydrogen evolution under ambient air diminishes with the increase in the concentration of surface Ti3+. This is explained by the over accumulation of Pt cocatalyst on the site of surface Ti3+ defect after the removal of adsorbed O2.
Revised: April 9, 2020 |
Published: January 1, 2018
Citation
Chen H., Z. Feng, W. Zhang, Y. Du, and G. Li. 2018.Negative impact of surface Ti3+ defects on the photocatalytic hydrogen evolution activity of SrTiO3.Applied Physics Letters 112, no. 1:Article No. 013901.PNNL-SA-131501.doi:10.1063/1.5009321