Table 2. Electricity generating profile under SP operation with three controlled anode potentials.
SP-H | SP-M | SP-L | ||||
---|---|---|---|---|---|---|
Anode potential (vs SHE) |
+100 mV |
–50 mV |
–200 mV |
|||
Reactor ID | a | b | a | b | a | b |
Phase I (day 55–75) | ||||||
Current (mA)a | 32.2 | 31.2 | 16.2 | 21.1 | 6.9 | 2.5 |
±s.d. | ±3.5 | ±2.6 | ±1.0 | ±4.2 | ±1.8 | ±1.0 |
Current density (mA cm−2)b | 0.325 | 0.315 | 0.163 | 0.213 | 0.069 | 0.026 |
±s.d. | ±0.035 | ±0.026 | ±0.010 | ±0.042 | ±0.018 | ±0.010 |
Max. current density (mA cm−2)b,c | 0.270 | 0.305 | 0.215 | 0.323 | 0.219 | 0.027 |
CE (%)d | 50 | 46 | 40 | 41 | 28 | 12 |
±s.d. | ±5 | ±4 | ±4 | ±4 | ±5 | ±6 |
Phase II (day 135–155) | ||||||
Current (mA)a | 24.2 | 19.9 | 20.0 | 21.7 | 7.0 | 3.5 |
±s.d. | ±2.9 | ±1.4 | ±2.0 | ±1.0 | ±1.0 | ±0.7 |
Current density (mA cm−2)b | 0.260 | 0.214 | 0.215 | 0.233 | 0.075 | 0.038 |
±s.d. | ±0.031 | ±0.015 | ±0.022 | ±0.011 | ±0.011 | ±0.008 |
Max. current density (mA cm−2)b,c | 0.297 | 0.246 | 0.297 | 0.358 | 0.235 | 0.044 |
CE (%)d | 43 | 41 | 43 | 40 | 35 | 21 |
±s.d. | ±3 | ±3 | ±2 | ±3 | ±4 | ±0 |
Abbreviations: CE, coulombic efficiency; SP, set-potential.
Averaged maximum current generation for repeated batch exchanges during SP operation.
Current density was calculated per projected anode surface area.
Maximum current density was determined by linear sweep voltammetry at day 62 (2-month) and at day 152 (5-month).
CE was calculated for each batch under SP operation, and averaged during the periods (phases I and II).