One-dimensional cobalt oxide nanotubes with rich defect for oxygen evolution reaction.

For the electrochemcial hydrogen production, the oxygen evolution reaction (OER) is a pivotal half-reaction in water splitting. However, OER suffers sluggish kinetics and high overpotential, leading to the increase of overall energy consumption and decrease of the energy efficiency. In this work, high-quality cobalt oxide porous nanotubes (CoO-PNTs) are easily obtained by simple self-template approach. One-dimensional (1D) porous structure provides the large specific surface area, enough abundant active atoms and effective mass transfer. In addition, CoO-PNTs also own self-stability of 1D architecture, benefitting the their durability for electrocatalytic reaction. Thus, CoO-PNTs with optimal annealing temperature and time reveal the attractive alkaline OER performance (Tafel slope of 56 mV decand 323 mV overpotential at 10 mA cm), which outperform the CoOnanoparticles and benchmark commercial RuOnanoparticles. Furthermore, CoO-PNTs also exhibit excellent OER durability for least 10 h at the 10 mA cm. Overall, CoO-PNTs with low cost can be serve as a highly reactive and economical catalyst for OER.