Cobalt nanorods decorated titanium oxide arrays as efficient and stable electrocatalyst for oxygen evolution reaction. (10th November 2021)

• Record Type: Journal Article
• Authors: Yang, Chenhui; Makabu, Cynthia Mulanga; Du, Xiaohang; Li, Jingde; Sun, Daolai; Liu, Guihua
• Is Part Of: Electrochimica acta. Volume 396(2021)
• Publication Date: 2021-11-10
• Subjects: Titanium oxide -- Cobalt nanorod -- Oxygen evolution reaction -- Anodic oxidation; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2021.139213
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Oxygen evolution reaction (OER) is a key process in many electrochemical energy conversion technologies, such as water electrolysis and zinc-air batteries. However, the efficiency of these electrocatalysis processes is usually hindered by the slow OER kinetics. Meanwhile, the oxidative reaction condition of OER also poses a great challenge for the long-term stability of OER catalysts. In this work, through anodic oxidation, hydrothermal reaction and calcination, a self-supported, efficient and stable OER catalyst (Co@TiO2 /Ti) was developed by loading Co nanoparticles on TiO2 nanotube array rooted on Ti foil. The TiO2 array substrate not only offers good corrosion resistance under the strong oxidative reaction condition of OER, but also provides an increased surface area for depositing the catalytic active Co-based catalysts. As a result, the Co@TiO2 /Ti catalyst shows excellent OER activity exhibiting an overpotential of 382 mV (j=50 mA cm −2 ) and onset potential of 1.46 V vs. RHE in 1M KOH solution. Importantly, it also achieves a high stability at high current density operating condition. In addition, post-OER reaction characterizations show that the Co nanoparticles were oxidized into Co3 O4 crystals, suggesting that the latter was the real component in catalyzing OER reaction. The self-supported efficient and stable catalyst and the insights revealed in the real OER catalysis phase advanced the development of OER catalysts. Graphical abstract: Image, graphical abstract .