Figure 3.

a) SEM images of the unsupported catalyst, U‐NC, as prepared and b) after 1 hour of CO₂RR at −0.95 V_RHE. d) TEM images of supported Cu nanocube, S‐NC, (23 wt %) catalyst, as prepared and e) after 1 hour of CO₂RR testing at −0.95 V_RHE. c) XRD patterns of the U‐NC catalyst and f) the S‐NC catalysis after initial deposition on a glassy carbon electrode (black), after 1 hour of CO₂RR at −0.66 V_RHE (blue) and after 1 hour at −0.95 V_RHE (red). XRD patterns of the blank glassy carbon plate and of the as prepared catalyst powders are displayed in Figure S7 for reference.