Fig. 5: The NO₃RR performance of ZnPc MDE(H) for the electrosynthesis of cyclohexanone oxime.

a ¹H-NMR spectra of standard cyclohexanone (CYC), standard cyclohexanone oxime, electrolytes after electrocatalysis, and electrolytes before electrocatalysis containing 1.0 M KOH + 1.0 M KNO₃ with 6 mM CYC. The yellow boxes indicate the detection of distinct peaks of cyclohexanone oxime in the electrolyte following catalysis, with no other distinctive peaks of side products such as cyclohexylamine. The abbreviation “arb. units” refers to “arbitrary units”. b NH₂OH and cyclohexanone oxime formation FE on ZnPc MDE(H) in NO₃RR with varying concentrations of CYC in 1.0 M KOH + 1.0 M KNO₃ electrolytes at an applied potential of −0.75 V. R_u of ZnPc MDE(H) in the electrolyte with 0, 6, 12 and 40 mM of CYC were 5.2 ± 0.2 Ω, 5.6 ± 0.1 Ω, 5.7 ± 0.1 Ω and 6.0 ± 0.2 Ω. Three individual measurements were taken with various working electrodes, and the average (mean) values are presented with the standard deviation as error bars. c Long-term electrosynthesis for a large amount of cyclohexanone oxime. The bars represent the conversion rate of CYC, and the symbols represent the concentration of CYC or cyclohexanone oxime in the electrolyte. Tested in a flow cell with a constant current of 250 mA using 0.5 L of electrolyte (1.0 M KOH + 1.0 M KNO₃, 40 mM CYC), R_u = 1.2 Ω.