Electrodeposition of High-Surface-Area IrO2 Films on Ti Felt as an Efficient Catalyst for the Oxygen Evolution Reaction

Yu Jin Park; Jooyoung Lee; Yoo Sei Park; Juchan Yang; Myeong Je Jang; Jaehoon Jeong; Seunghoe Choe; Jung Woo Lee; Jung-Dae Kwon; Sung Mook Choi

doi:10.3389/fchem.2020.593272

Electrodeposition of High-Surface-Area IrO₂ Films on Ti Felt as an Efficient Catalyst for the Oxygen Evolution Reaction

Front Chem. 2020 Oct 23:8:593272. doi: 10.3389/fchem.2020.593272. eCollection 2020.

Authors

Yu Jin Park^{1

2}, Jooyoung Lee¹, Yoo Sei Park^{1

2}, Juchan Yang¹, Myeong Je Jang¹, Jaehoon Jeong¹, Seunghoe Choe¹, Jung Woo Lee², Jung-Dae Kwon¹, Sung Mook Choi¹

Affiliations

¹ Surface Technology Division, Materials Center for Energy Department, Korea Institute of Materials Science, Changwon, South Korea.
² Department of Materials Science and Engineering, Pusan National University, Busan, South Korea.

Abstract

Under acidic conditions, IrO₂ exhibits high catalytic activity with respect to the oxygen evolution reaction (OER). However, the practical application of Ir-based catalysts is significantly limited owing to their high cost in addition to the scarcity of the metal. Therefore, it is necessary to improve the efficiency of the utilization of such catalysts. In this study, IrO₂-coated Ti felt (IrO₂/Ti) electrodes were prepared as high-efficiency catalysts for the OER under acidic conditions. By controlling the surface roughness of the Ti substrate via wet etching, the optimum Ti substrate surface area for application in the IrO₂/Ti electrode was determined. Additionally, the IrO₂ film that was electrodeposited on the 30 min etched Ti felt had a large surface area and a uniform morphology. Furthermore, there were no micro-cracks and the electrode obtained (IrO₂/Ti-30) exhibited superior catalytic performance with respect to the OER, with a mass activity of 362.3 A $g_{Ir}^{- 1}$ at a potential of 2.0 V (vs. RHE) despite the low Ir loading (0.2 mg cm^-2). Therefore, this proposed strategy for the development of IrO₂/Ti electrodes with substrate surface control via wet etching has potential for application in the improvement of the efficiency of catalyst utilization with respect to the OER.

Keywords: electrodeposition; iridium oxide; oxygen evolution reaction; surface area; wet etching.