Fig. 4: ESAE reaction analysis over Cu-PCC and Cu-C.

a Schematic illustration of the equipment used in the DEMS analysis. b, c LSV curves and the corresponding DEMS signals of Cu-PCC and Cu-C. d, e Square wave potentials and the corresponding DEMS signals of Cu-PCC and Cu-C. R: 1.5 ± 0.1 Ω.