N-doped CoO nanowire arrays as efficient electrocatalysts for oxygen evolution reaction

Rational design of cost-effective high-performance electrocatalysts for oxygen evolution reaction (OER) is of great significance for electrochemical water splitting. Herein, we adopt a nitrogen doping method to fabricate self-supported N-doped CoO nanowire arrays (N-CoO) as active electrocatalysts via a facile hydrothermal combined doping method. The N-CoO nanowires are strongly composited with the carbon cloth substrate forming free-standing electrode with reinforced stability and high electronic conductivity. Owing to the increased accessible and electroactive areas, rich/short pathways for charge transfer and enhanced electronic conductivity, the N-CoO electrode exhibits excellent electrocatalytic performance for OER with a low overpotential (319 mV at 10 mA cm(-2 )and 410 mV at 100 mA cm(2)) and a low Tafel slope of 74 mV dec(-1) as well as superior long-term stability with no decay in 24h continuous test in alkaline solution. Our reported design and optimization strategy provide a promising way to construct interesting well-aligned arrays for application in energy storage and conversion. (C) 2018 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.