Table 1. XANES Pre-Edge Energies and EXAFS Fitting Data of Co/SiO₂ and Co–Zr/SiO₂.

sample	pre-edge energy (keV)	oxidation state	CN	R (Å)	σ2	E0 (eV)	S02
Co/SiO2 as-prepared	7.7092	+2	3.7 (±0.5)	1.98 (±0.01)	0.005	–8.5 (±2.0)	0.81
Co/SiO2 post-reaction	7.7092	+2	4.0 (±0.8)	1.97 (±0.02)	0.008	–2.0 (±3.2)	0.82
Co–Zr/SiO2 as-prepared	7.7092	+2	5.7 (±0.7)	2.05 (±0.01)	0.009	–7.9 (±1.7)	0.88
Co–Zr/SiO2 post-reaction	7.7092	+2	4.1 (±0.6)	1.99 (±0.02)	0.009	–4.0 (±2.2)	0.86