Effects of phosphate precursors on morphology and oxygen evolution reaction activity of NiFe (oxy)hydroxide on nickel foams

NiFe (oxy)hydroxides nanosheets were synthesized on nickel foams via co-precipitation and electrochemical activation. It is found that the phosphate precursors (Na 3 PO 4 , Na 2 HPO 4 and NaH 2 PO 4 ) have diverse effects on the morphology and thus the oxygen evolution reaction activity of the formed final catalysts. The resulting NiFe (oxy)hydroxides nanosheets prepared with Na 2 HPO 4 demonstrate a low overpotential of 205 mV to achieve a current density of 50 mA/cm 2 with a Tafel slope down to 30 mV/dec in 1 mol/L KOH, and remain stable for 20 h during stability test.