Construction of Flower-like FeCo2O4 Nanosheets on Ni Foam as Efficient Electrocatalyst for Oxygen Evolution Reaction

Developing efficient transition metal oxide electrodes is essential to energy conversion and storage. In this work, flower-Like FeCo2O4 nanosheets supported on Ni foam were synthesized by facile hydrothermal and calcination treatment. Various temperatures influence the morphologies and oxygen evolution reaction activities. Especially, FeCo2O4/NF-120 °C catalysts showed the best oxygen evolution reaction (OER) activity due to the fact that 3D Ni foam provided good conductive substrate-forming FeCo2O4 nanosheets, which enhanced the electrochemical stability and facilitated the transport of electrolyte and release of oxygen. In addition, the synergistic effect between Fe and Co also enhanced active sites and promoted the OER catalytic performance. The flower-like FeCo2O4/Ni electrodes showed a low overpotential of 124 and 339 mV at the current density of 10 and 50 mA cm−2 for OER, respectively. Also, they displayed a low tafel slope of 43.78 mV dec−1 and good stability in alkaline electrolyte. This research could promote the design of low-cost electrocatalysts for OER.