Fig. 4: Electrochemical stability of Co3O4@C/GPO electrodes.

Chronopotentiometry measurements at j = 10 mA cm–2 in 1 M H2SO4 electrolyte. a 40-Co3O4@C/GPO (>40 h). b 20-Co3O4@C/GPO (2 h). c 30-Co3O4@C/GPO (2 h). d Benchmarking of their activity/stability features (red stars) in comparison with other OER electrocatalysts (black squares) in the same electrolysis conditions according to the data from a previous benchmarking study6. Source data are provided as a Source Data file.