Fig. 3. (A) RDE LSV curves of different catalysts at a rotation rate of 1600 rpm with a scan rate of 10 mV s−1. (B) Polarization curves of all catalysts. The ionic resistance (∼45 Ω) from the solution was determined via iR compensation test. (C) Oxygen electrode activities within the ORR and OER potential windows of various catalysts dispersed on the glass carbon electrode in O2-saturated 0.1 M KOH. (D) OER linear sweep voltammograms of all Co–N/CN catalysts in O2-saturated 0.10 M KOH before and after 1000 cycles.
