Facile Synthesis of Fe-Doped CoO Nanotubes as High-Efficient Electrocatalysts for Oxygen Evolution Reaction

Developing high-performance, low-cost, and robust electrocatalysts is of great importance to boost the efficiency of oxygen evolution reaction (OER). Herein, based on the integrated design of chemical composition and geometric structure, Fe-doped CoO nanotubes (NTs) with high OER activity are prepared by a facile template-free approach. The construction of this tubular structure is realized via a simple wet-chemical reaction to prepare solid nanorods as precursor and a subsequent calcination treatment of the precursor to form hollow cavity. The favorable composition and unique hollow structure endow these Fe-doped CoO NTs with remarkable activity toward OER. When used as the electrocatalyst for OER, the Fe-doped CoO NTs show a small overpotential of 282 mV at the current density of 10 mA cm −2 , a low Tafel slope of 78.26 mV dec −1 , and a high turnover frequency of 0.0965 s −1 at the overpotential of 282 mV, which is superior to those of CoO NTs and solid CoO nanoparticles. Moreover, the Fe-doped CoO NTs also exhibit excellent long-term stability of 24 h at the current density of 10 mA cm −2 .