NiFe2O4/NiO Nanocomposites as Electrocatalysts for Oxygen Evolution Reaction

NiFe2O4/NiO nanocomposites were prepared by the thermal treatment of a single. source NiFe. layered double hydroxide precursor and were used as electrocatalysts for electrooxidation of water( oxygen evolution reaction, OER). The NiFe2O4/NiO nanocomposites exhibited much higher water oxidation activity and better stability than pure NiFe2O4, NiO and a physical mixture of NiFe2O4 and NiO synthesized by chemi. cal coprecipitation method. A current density of 10 mA/cm(2) was reached at an overpotential of 364 mV in al. kaline media. The good electrocatalytic performance for OER could presumably be attributed to that the well. dispersed heterogeneous structure of the nanocomposites prevented the aggregation of NiFe2O4 and resulted in a higher surface area and a smaller charge transfer resistance compared with the control samples.