Morphology regulated synthesis of NiFe-layered double hydroxide nanostructures on nickel foam toward efficient oxygen evolution reaction

Developing electrocatalysts with excellent catalytic capability and stability is a major challenge for oxygen evolution reaction (OER). With the aid of F- provided by NH4F, NiFe-LDH in situ grown on Ni foam (NF) with high OER performance was prepared by a simple hydrothermal method. NiFe-LDH/NF-8 only requires a low Tafel slope of 41.9 mV dec-1, and low OER overpotentials of 225 mV and 239 mV to drive the current densities of 50 mA cm-2 and 100 mA cm-2, respectively. Meanwhile, it exhibits eminent stability under the high current density of 100 mA cm-2 for more than 60 hours. The conclusions prove that the high electrocatalytic property of the material is related to the large surface area of nanosheet morphology and stable binding between the NiFe-LDH and the substrate of NF. The dynamic reconstruction mechanism is unraveled to further understand the species variation in OER, which will be helpful to design efficient electrocatalysts.