Fig. 6. (a) Cyclic Voltammetry (CV) of the Cu-wire electrode at 50 mV s⁻¹ scan rate sweeping in a potential window from 1.37 V to −1.3 V vs. RHE. (b–d) Effect of oxidative pulses on the FRR on a Cu-wire electrode in a 0.12 M PBS solution at pH_initial = 11.3: (b) electrochemical conversion, (c) Faradaic efficiency, (d) isomerisation and (e) the pH. Conditions: i = −20 mA (j = −5.3 mA cm⁻²), AMVN membrane as separator, constant pH titration with 10 μL min⁻¹ of 0.5 M H₃PO₄, 3 h at room temperature (21 °C).