Table 1 Rates, reversibility and the degree of rate control (DRC) of the ten elementary steps of the microkinetic model
From: On the origin of multihole oxygen evolution in haematite photoanodes
Parameters: | C(h+) = 1 ML | C(h+) = 10−2 ML | ||||
|---|---|---|---|---|---|---|
\({E}_{{{{\rm{diff}}}}}^{{{{\rm{h}}}}}\) = 0.29 eV | Θ(*O1−) = 0.13 ML | Θ(*O1−) = 7.4 × 10−3 ML | ||||
Eapp = 0.18 eV | Eapp = 0.21 eV | |||||
\({{{\mathcal{O}}}}\)(C(h+)) = 1.15; 𝒪(Θ(*O1−)) = 3.07 | \({{{\mathcal{O}}}}\)(C(h+)) = 2.94; 𝒪(Θ(*O1−)) = 3.00 | |||||
Reaction | Rate (s–1) | kb/kf | DRC | Rate (s–1) | kb/kf | DRC |
1: *OH− + h+ + OH− → *O1− + H2O | 6.32 × 101 | 1.48 × 10–1 | 0.89 | 1.56 × 10–2 | 9.81 × 10–1 | 0.05 |
2: *O1− + h+ + OH− → *OOH− | 2.00 × 10–1 | 1.24 × 10–7 | 0.00 | 1.95 × 10–7 | 3.92 × 10–8 | 0.00 |
3: *OOH− + h+ + OH− → *OO− + H2O | 1.07 | 8.83 × 10–6 | 0.02 | 2.83 × 10–6 | 6.40 × 10–2 | 0.00 |
4: *OO− + h+ + OH− → O2 + *OH− | 2.08 × 10–4 | 9.00 × 10–17 | 0.00 | 7.03 × 10–9 | 1.77 × 10–13 | 0.00 |
5: *OO− + *O1− + H2O → O2 + 2*OH− | 2.14 × 101 | 3.65 × 10–16 | 0.00 | 5.20 × 10–3 | 5.66 × 10–13 | 0.00 |
6: 2*O1− + H2O → *OOH− + *OH− | 5.56 × 10–16 | 5.80 × 10–6 | 0.00 | 4.77 × 10–23 | 2.76 × 10–7 | 0.00 |
7: 3*O1− + H2O → *OO− + 2*OH− | 2.16 × 10–9 | 5.04 × 10–12 | 0.00 | 3.92 × 10–14 | 1.18 × 10–9 | 0.00 |
8: 2*O1− + OH− → *OOH− + *O2− | 8.73 × 10–1 | 4.27 × 10–1 | 0.00 | 2.63 × 10–6 | 9.94 × 10–1 | 0.00 |
9: 3*O1− + OH− → *OO− + *OH− + *O2− | 2.04 × 101 | 4.98 × 10–22 | 0.09 | 5.19 × 10–3 | 3.34 × 10–21 | 0.94 |
10: *O2− + h+ → *O1− | 2.12 × 101 | 2.39 × 10–3 | 0.00 | 5.20 × 10–3 | 4.12 × 10–1 | 0.00 |
