122nd General Meeting of the KCS

Type Symposium
Area Electrochemical Energy Conversion and Storage: Progress and New Challenges
Room No. Room 320
Time THU 16:30-:
Code ELEC1-3
Subject Corrosion engineering toward high-performance electrodes for oxygen evolution and water splitting
Authors Byungkwon Lim
Sungkyunkwan University, Korea
Abstract Corrosion is generally considered to be an undesirable process that leads to damage and failure of a material, typically a metal or alloy, but understanding and control of surface processes involved in corrosion may enable its utilization in a more productive way. We show that simply by corroding Ni foam in an aqueous solution, it is possible to produce high-performance oxygen evolution electrodes. When Ni foam was corroded in water or an aqueous solution containing NaCl, a dense array of Ni(OH)2 nanosheets was produced on the surface of the foam. When corroded in the presence of RuCl3, the nanostructured surface composed of Ni(OH)2 nanosheets decorated with ultrasmall RuO2 nanoparticles was obtained. At an applied voltage of 1.7 V, the combination of these two nanostructured surfaces yielded a water-splitting current density more than three times that obtained on the commercial Pt wire electrodes. Futhermore, we also fabricated a high-performance OER electrode consisting of a dense array of ternary NiFeCo layered double hydroxide (LDH) nanosheets by corroding a Ni foam in an aqueous solution containing Fe3+ and Co2+ cations. This electrode exhibited a small overpotential of 170 mV at current density of 10 mA cm−2 in 1 M KOH. This OER electrode was coupled with a CoP-based hydrogen evolution reaction electrocatalyst to construct an alkaline electrolyzer, which achived the current density of 10 mA/cm2 only at an applied voltage of 1.49 V in 1 M KOH. It is anticipated that our approach could also be extended to fabricate ternary or higher LDH electrodes with desired compositions for OER and other catalytic applications.
E-mail blim@skku.edu