Table 2. Insertion Energy of the First TM Atom into One Lattice Ce Position Atom (Eads-TM1) and the Second TM Atom (Eads-TM2) with Respect to Corresponding TM Bulk Atomsa.
| TM1/TM-dop-II | Ni | Pd | Pt | Cu | Rh | Zn |
|---|---|---|---|---|---|---|
| Eads (TM1, eV) | –4.79 | –3.62 | –4.04 | –4.20 | –4.24 | –4.79 |
| Eads (TM2, eV) | –2.03 | –1.66 | –0.61 | –1.22 | –1.21 | –3.65 |
| Eads (CH4, eV) | –0.42 | –0.59 | –0.81 | –0.41 | –0.46 | –0.17 |
| Ea (eV) | 0.62 | 0.60 | 0.49 | 0.75 | 0.52 | 1.10 |
| ΔE (eV) | –0.42 | –0.49 | –0.77 | –0.70 | –0.55 | 0.52 |
| r (molecules·site–1·s–1) | 1.41 × 100 | 5.57 × 101 | 3.30 × 104 | 9.42 × 10–2 | 2.12 × 101 | 1.04 × 10–6 |
a
Adsorption energy Eads, activation energy Ea, reaction energy ΔE of CH4 dehydrogenation, and the rate of CH4 dissociation by TM1/TM-dop-II. PCH4 = 0.1 atm, and T = 623 K.