OER performance of Ni_xCo_1−xO_y in 1.0 M KOH solution compared with literature.

Catalyst	Electrolyte	η 1 @1 mA cm−2 (mV)	η 10 @10 mA cm−2 (mV)	Tafel slope (mV dec−1)	Ref.
NixCo1−xOy	1.0 M KOH	339	404	52.7	This work
CuO-from Cu-EA	1.0 M KOH	370	475	90	2
Co3O4	0.1 M KOH	—	450	89	5
F-Ni-2	1.0 M KOH	—	330	53	7
F-NiAl LDH-NF	1.0 M KOH	—	250	77	7
PtNi/Mn2O3–NiO	0.1 M KOH	—	529	140	8
RuO2/Co3O4	1.0 M KOH	—	305	69	14
Ir/Ni oxide	1.0 M KOH		264	31	15
NiCo2O4 nanoflowers	1.0 M KOH	—	383	137	18
NiCo2O4 hollow nanospheres	1.0 M KOH	—	428	141	18
MoO3/Ni–NiO	1.0 M KOH	347 @100 mA cm−2	—	60	19
10% Ni-doped Mn3O4	1.0 M KOH	235 @5 mA cm−2	283	165	20
NG02 (NiFe2O4/rGO 2 : 5 wt%)	1.0 M KOH	—	302	63	21
NiO/NF	1.0 M KOH	—	310	54	22
NiCo2O4	1.0 M KOH	—	292	62	23
NiCo2O4/rGO (nanonet)	0.1 M KOH	—	450	53	25
NiCo2O4/rGO (microsphere)	0.1 M KOH	—	510	62	25
NiMoO4 nanorods	1.0 M KOH	—	340	45.6	27
Cu2O–Cu hybrid foams	1.0 M KOH	—	250	67.52	28
Ni–Fe oxide	0.1 M KOH	420 @50 mA cm−2	328	42	29
Co0.25Ni0.75Fe2O4	1.0 M KOH	380 @5 mA cm−2	450	50.5	32
Co0.5Ni0.5Fe2O4	1.0 M KOH	418 @5 mA cm−2	477	73.0	32
Co0.75Ni0.25Fe2O4	1.0 M KOH	401 @5 mA cm−2	460	52.2	32