Thermal decomposition behavior of nickel-iron hydrotalcite and its electrocatalytic properties of oxygen reduction and oxygen evolution reactions

The thermal decomposition behavior of NiFe layered double hydroxide (LDH) was investigated by thermogravimetric analysis-differential scanning calorimetry (TG-DSC). The calcined product at 500 °C was mainly NiO/FeOx composite oxide, of which FeOx was amorphous oxide; the calcined product at 650 °C was mainly NiO/NiFe2O4 composite oxide. The polarization curves and chronopotentiometry stated that the NiO/FeOx and NiO/NiFe2O4 showed good electrocatalytic OER and ORR activity; the OER activity of NiO/FeOx was better than that of NiO/NiFe2O4; the ORR activity of NiO/NiFe2O4 was better than that of NiO/FeOx.