Table 1. Differential Enthalpy ΔHads and Differential Gibbs Free Energy ΔGads for Physical Adsorption and Differential Enthalpy of Decomposition ΔHdec (all in kJ/mol) for Molecular Oxygen and Water on Defect-Free (i) PtTe2- and (ii) Pt2Te2-Terminated Pt3Te4 Surfaces and, Moreover, in the Nearness of Te Vacancies in These Surfaces (See Figure 1b,c)a.
| adsorbent | surface termination of Pt3Te4 | site | ΔHads [kJ/mol] | ΔGads [kJ/mol] | ΔHdec [kJ/mol] |
|---|---|---|---|---|---|
| CO | PtTe2 | defect-free | –15.61 | +3.74 | – |
| Te vacancy | –12.72 | +6.63 | |||
| Pt2Te2 | defect-free | –21.07 | –1.72 | – | |
| Te vacancy | –12.59 | +6.76 | |||
| H2O | PtTe2 | defect-free | –25.59 | +5.71 | +405.20 |
| Te vacancy | –20.11 | +11.19 | +428.38 | ||
| Pt2Te2 | defect-free | –26.07 | +5.23 | +173.55 | |
| Te vacancy | –16.48 | +14.82 | –30.18 | ||
| O2 | PtTe2 | defect-free | –42.62 | –31.13 | –51.78 (+1.31) |
| Te vacancy | –33.29 | –21.99 | –69.37 (−30.99) | ||
| Pt2Te2 | defect-free | –40.81 | –29.51 | –98.08 (−27.06) | |
| Te vacancy | –34.99 | –23.69 | –162.98 (−73.58) |
a
In the case of oxygen decomposition, we also report the differential enthalpy of the oxidation of whole surface (in parentheses).