Fig. 3: Understanding reaction sites and mechanisms in the DOP.
a Calculated adsorption energy (Ead) of different sites on the catalyst surface towards PDS and BPA. b, c Calculated charge density difference for PDS and BPA absorption, respectively, on different sites on the Cu-N-C surface. Yellow and blue isosurfaces represent charge accumulation and depletion in the space, respectively. d Schematic of the possible detailed reaction process facilitated by the CuN2 sites on Cu-N-C@GF electrodes during the DOP. e Monitoring of removal performance towards different organic pollutants using the double-chamber reactor. Reaction conditions: PDS, 10 mM; pollutants, 5 μM; NaCl, 0.5 wt‰. Experiments were conducted in triplicate, and the error bars represent the arithmetic mean ± standard deviation. f Schematic of the potential differences (ΔE1, ΔE2) generated between the electrode Cu-N-C@GF with the respective co-existence of organics/PDS. g Comparison of the BPA removal ratio in the DOP system with different catalytic electrodes: Cu-N-C@GF, CuO@GF and CNTs@GF. Conditions: BPA, 5 μM; PDS, 10 mM; NaCl, 0.5 wt‰. Experiments were conducted in triplicate, and the error bars represent the arithmetic mean ± standard deviation. h Comparison of the measured potential differences between the two ends, under different electrode-based double-chamber systems.
