| Catalyst | peak position of O 1s (eV) | Surface content of O | |
| Lattice oxygen (%) | Hydroxyl (%) | ||
| Au/Mg(OH)2-CeO2 (6.5%) * | 530.44 | 44.02 | 55.98 |
| Au/Mg(OH)2-CeO2 (20%) | 530.58 | 48.70 | 51.30 |
| Au/Mg(OH)2-CeO2 (37.5%) | 531.33 | 56.76 | 43.23 |
| Au/Mg(OH)2-CeO2 (50%) | 531.45 | 50.54 | 49.46 |
| Au/Mg(OH)2 | 531.51 | 33.34 | 66.66 |