Research Article
TiO2-CdS Nanocomposites: Effect of CdS Oxidation on the Photocatalytic Activity
Table 2
Corrected binding energies (eV) and, in brackets, atomic concentration (%). Also, atomic ratios sulphate to sulphide and Cd or S to Ti are shown.
| | CdS | TiO2-0.5CdS | TiO2-0.2CdS | TiO2-0.1CdS | TiO2-0.03CdS | Assignments |
| C 1s | 285.0 [38.6] | 284.9 [24.2] | 285.0 [28.6] | 284.9 [34.6] | 284.5 [25.2] | CH aliphatic | 286.7 [7.6] | 286.4 [1.9] | 286.6 [3.0] | 286.4 [3.9] | 285.9 [3.5] | C-O | | 288.7 [1.4] | 289.0 [2.1] | 288.9 [2.0] | 288.7 [1.4] | C=O |
| O 1s | | 530.0 [38.3] | 530.1 [37.7] | 529.9 [33.5] | 529.7 [42.6] | TiO2 | 532.1 [14.4] | 531.6 [7.5] | 532.0 [5.6] | 531.8 [5.3] | 531.4 [5.1] | , C=O | 533.8 [3.1] | 533.1 [2.4] | 533.4 [2.8] | 533.1 [2.9] | 532.6 [2.1] | C-O |
| S 2p3/2 | 161.9 [10.5] | 161.5 [0.87] | 161.5 [0.73] | 161.5 [0.40] | 161.5 [0.12] | CdS | S 2p1/2 | 163.1 [5.3] | 162.7 [0.43] | 162.7 [0.36] | 162.7 [0.20] | 162.8 [0.06] |
| S 2p3/2 | 168.5 [0.7] | 168.6 [0.47] | 168.6 [0.22] | 168.5 [0.31] | 168.7 [0.12] | | S 2p1/2 | 169.7 [0.3] | 169.8 [0.23] | 169.8 [0.11] | 169.7 [0.15] | 169.8 [0.06] |
| Cd 3d5/2 | 405.3 [19.5] | 405.3 [2.1] | 405.3 [1.7] | 405.5 [0.7] | 405.7 [0.3] | CdS and CdSO4 |
| Ti 2p3/2 | | 458.8 [13.9] | 458.8 [12.0] | 458.8 [10.9] | 458.8 [13.7] | TiO2 | Ti 2p1/2 | | 464.5 [6.3] | 464.5 [5.2] | 464.5 [5.1] | 464.6 [5.8] |
| Atomic ratio |
| | 0.06 | 0.54 | 0.31 | 0.77 | 1.03 | | Cd/Ti | | 0.11 | 0.10 | 0.05 | 0.01 | | S/Ti | | 0.10 | 0.08 | 0.07 | 0.02 | |
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