FeOOH/Ni heterojunction nanoarrays on carbon cloth as a robust catalyst for efficient oxygen evolution reaction

Developing catalysts based on transition metal-based materials for oxygen evolution reaction (OER), which are cheap and efficient, is one of the keys to increase the rate of electrolysis of water to produce hydrogen. Herein, we successfully synthesize iron hydr(oxy)oxide nano-arrays on carbon cloth (FeOOH@CC), and then metallic nickel is electrodeposited on its surface to fabricate FeOOH/Ni heterojunction nanoarrays. Notably, the optimal FeOOH/Ni heterojunction nanoarrays catalyst shows high electrocatalytic performance toward OER with a small overpotential of 257.8 mV at 50 mA cm⁻², a Tafel slope of 30.8 mV dec⁻¹ and outstanding long-term stability in alkaline media. The superior OER performance could be ascribed to the introducing of metallic nickel. The nickel in-situ grows on the surface of FeOOH, which not only can improve the conductivity of FeOOH, but also cooperate with FeOOH to form the FeOOH/Ni heterogeneous interfaces for further enhancing OER electrocatalytic activities. This work provides a simple and efficient strategy of interface engineering to fabricate oxyhydroxide/metal heterojunction nanoarrays as high-efficiency OER catalysts.