fig2

Figure 2. (A) H₂-TPR curves of Ru₁/o-CeO₂-ov, Ru₁/c-CeO₂-ov, and Ru₁/r-CeO₂-ov. EPR (B) and O 1s XPS (C) spectra of x-CeO₂ and Ru₁/x-CeO₂-ov. Deconvoluted O 1s XPS spectra of Ru₁/x-CeO₂-ov (D) and x-CeO₂ (E); Deconvoluted Ce 3d XPS spectra of Ru₁/x-CeO₂-ov (F) and x-CeO₂ (G); (H) Comparison of relative oxygen vacancy contents of Ru₁/x-CeO₂-ov and x-CeO₂. H₂-TPR: Hydrogen temperature-programmed reduction; EPR: electron paramagnetic resonance; XPS: X-ray photoelectron spectroscopy.