Liu CTseng C.-YWang Y.-CI-CHUN CHENGJIAN-ZHANG CHEN2022-11-162022-11-16202219961944https://www.scopus.com/inward/record.uri?eid=2-s2.0-85128316929&doi=10.3390%2fma15072603&partnerID=40&md5=61ef4b94c623a6f577794f9e55a94822https://scholars.lib.ntu.edu.tw/handle/123456789/625328In this paper, low-pressure 95%Ar–5%H2, pure Ar, and 95%Ar–5%O2 plasmas were used for post-treatment of ruthenium (Ru) deposited on nickel foam (NF) (Ru/NF). Ru/NF was then tested as a catalyst for a hydrogen evolution reaction. Significant improvement in electrocatalytic activity with the lowest overpotential and Tafel slope was observed in an alkaline electrolyte (1 M KOH) with 95%Ar–5%O2 plasma processing on Ru/NF. Linear scanning electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV) also indicate the lowest interfacial impedance and largest electrical double layer capacitance. Experimental results with 0.1 M phosphate buffered saline (PBS) and 0.5 M H2SO4 electrolytes were also demonstrated and compared. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.catalyst; electrolysis; hydrogen evolution reaction; plasma; ruthenium (Ru)Cyclic voltammetry; Electrocatalysts; Electrolytes; Hydrogen; Potassium hydroxide; Ruthenium compounds; Electrocatalytic activity; Hydrogen evolution reactions; Low pressure plasma; Low pressures; Nickel foam; Overpotential; Post treatment; Ruthenium; Tafel slopes; ]+ catalyst; Rutheniumjournal article10.3390/ma150726032-s2.0-85128316929