Restructured <scp>Co‐Ru</scp> alloys via electrodeposition for efficient hydrogen production in proton exchange membrane water electrolyzers
Taegyeom Lee, Yoonsu Park, Hoyoung Kim, Yun‐Kun Hong, Eunseo Hwang, Minyoung Kim, Soo‐Kil Kim, Don‐Hyung Ha
Abstract
The design of robust and high-performance hydrogen evolution reaction (HER) catalysts is crucial for the scalable production of hydrogen by electrochemical water splitting. In this work, we fabricated hierarchically porous Co-Ru catalysts with excellent catalytic activity and durability in acidic media. The morphology of the Co-Ru catalysts was successfully controlled through an optimized electrochemical process. Among all Co-Ru samples prepared in this study, the Co72Ru28 catalyst exhibited the largest catalytic surface area, as well as excellent HER activity (overpotential of 26.4 mV at −10 mA cm−2) and durability. X-ray photoelectron spectroscopy measurements revealed the electron transfer between Co and Ru, indicating that the formation of the Co-Ru alloy improved the activity and durability of the catalyst. Furthermore, a proton exchange membrane water electrolyzer (PEMWE) prepared with the Co72Ru28 sample showed excellent performances (3.4 A cm−2 at 2.0 Vcell), illustrating the promising potential of the present Co-Ru catalysts as cathode materials for PEMWE systems.