Synthesis and Characterization of the Cu<sub>0.72</sub>Co<sub>2.28</sub>O<sub>4</sub> Catalyst for Oxygen Evolution Reaction in an Anion Exchange Membrane Water Electrolyzer
Sung‐Min Park, Myeong Je Jang, Yoo Sei Park, Jooyoung Lee, Jae‐Yeop Jeong, Jaehoon Jung, Min-Kwan Choi, Yuseong Noh, Min Ho Seo, Hyung Ju Kim, Juchan Yang, Yang Do Kim, Sung Mook Choi
Abstract
In this study, we investigated the morphological, crystal structural, electronic structural, and electrocatalytic properties of the inverse spinel structured copper cobalt oxide (Cu 0.72 Co 2.28 O 4 ) catalysts. The materials were prepared by coprecipitation using various copper and cobalt precursors, and subsequent oxidation treatment. Electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer Emmett Teller (BET) analyses were employed to characterize the Cu 0.72 Co 2.28 O 4 catalysts. The Cu 0.72 Co 2.28 O 4 catalyst, synthesized with acetate based precursors, exhibited higher activity for the oxygen evolution reaction than commercial precious IrO 2 catalyst. This performance was attributed to its high surface area, sheet morphology and ratio of Co 3+ . The Cu 0.72 Co 2.28 O 4 catalyst also showed excellent stability with a performance of 99% after 300 hours. The Cu 0.72 Co 2.28 O 4 catalyst anode electrode was coupled with a Pt/C cathode electrode to construct an anion exchange membrane water electrolysis (AEMWE) cell. Our AEMWE cell achieved a current density of 644 mA/cm 2 and an energy efficiency of 85% at a cell voltage of 1.8 V in 1M KOH.