Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (54권1호 1-11)

Electrochemical properties of porous AuCu dendrite surface for the oxygen reduction reaction in alkaline solutions

알칼리 수용액에서 산소환원반응에 대한 다공성 AuCu 덴드라이트 표면의 전기화학적 특성 평가

김민영;이종원;조수연;박다정;정현민;이주열;이규환;
Kim, Min-Yeong;Lee, Jong Won;Cho, Soo Yeon;Park, Da Jung;Jung, Hyun Min;Lee, Joo Yul;Lee, Kyu Hwan;

한국재료연구원 표면기술본부 전기화학연구실;
Department of Electrochemistry, Surface Technology Division, Korea Institute of Materials Science(KIMS);

DOI : 10.5695/JKISE.2021.54.1.1

Abstract

Porous dendrite structure AuCu alloy was formed using a hydrogen bubble template (HBT) technique by electroplating to improve the catalytic performance of gold, known as an excellent oxygen reduction reaction (ORR) catalyst in alkaline medium. The rich Au surface was maximized by selectively electrochemical etching Cu on the AuCu dendrite surface well formed in a leaf shape. The catalytic activity is mainly due to the synergistic effect of Au and Cu existing on the surface and inside of the particle. Au helps desorption of OH- and Cu contributes to the activation of O2 molecule. Therefore, the porous AuCu dendrite alloy catalyst showed markedly improved catalytic activity compared to the monometallic system. The porous structure AuCu formed by the hydrogen bubble template was able to control the size of the pores according to the formation time and applied current. In addition, the Au-rich surface area increased by selectively removing Cu through electrochemical etching was measured using an electrochemical calculation method (ECSA). The results of this study suggest that the alloying of porous AuCu dendrites and selective Cu dissolution treatment induces an internal alloying effect and a large specific surface area to improve catalyst performance.

Keywords

oxygen reduction reaction;AuCu;alloy;etching;porous surface;dendrite;