Comparison of electrochemical performance of our catalyst Co-doped FeO_x NRs film for OER in alkaline condition with that published relating to iron oxides-based electrocatalysts.

Anodic catalysts	Overpotential at 10 mA cm−2, mV	Current density, mA cm−2	Tafel slope, mV dec−1	Stability, h	Electrolyte conc., M	Ref.
10%Co3O4@2%FeOx/G-110	1.55 V vs. RHE	50 mA cm−2 at 1.55 VRHE	63	25 h	1.0 M KOH	65
SC/FeOx-NBs/FTO	1.50 V vs. RHE	120 mA cm−2 at 1.50 VRHE	54	24 h	0.5 M KOH	46
CoOx + Fe3+ (0.3 mM) catalyst	1.55 V vs. RHE	∼750 mA cm−2 at 1.55 VRHE	27.6	25 h at 10 mA cm−2	1.0 M KOH	47
Fe–Mn–O NSs/CC	1.50 V vs. RHE	100 mA cm−2 at 1.55 V vs. RHE	63.9	12 h at 10 mA cm−2	1.0 M KOH	62
NiFe-LDH NSs	1.50 V vs. RHE	200 mA cm−2 at 1.60 VRHE	47	20 h	N2-saturated 1 M KOH	66
Fe–NiO–Ni CHNAs	1.475 V vs. RHE	120 mA cm−2 at 1.475 VRHE	∼43.4	24 h at 10 mA cm−2	1.0 M KOH	67
P–CoSe2/N–C	1.48 V vs. RHE	70 mA cm−2 at 1.45 VRHE	36	10 h at 10 mA cm−2	Alkaline medium	50
Co-doped FeO/FTO NRs	1.54 V vs. RHE	30 mA cm−2 at 1.65 VRHE	61	12 h at 1.55 VRHE	Air-saturated 1 M KOH	Our work