Plasma-Deposited Ru-Based Thin Films for Photoelectrochemical Water Splitting

• Published in: Catalysts Vol. 10; no. 3; p. 278
• Main Authors: Lukasz Jozwiak, Jacek Balcerzak, Jacek Tyczkowski
• Format: Journal Article
• Language: English
• Published: MDPI AG 01-03-2020
• Subjects: oxygen evolution reaction; plasma deposition; ruthenium oxide; thin-film catalyst; water splitting
• ISSN: 2073-4344
• DOI: 10.3390/catal10030278

Plasma-enhanced chemical vapor deposition (PECVD) was used to produce new Ru-based thin catalytic films. The surface molecular structure of the films was examined by X-ray photoelectron spectroscopy (XPS). To determine the electro- and photoelectrochemical properties, the oxygen evolution reaction (OER) process was investigated by linear sweep voltammetry (LSV) at pH = 13.6. It was found that Ru atoms were mainly in the metallic state (Ru0) in the as-deposited films, whereas after the electrochemical stabilization, higher oxidation states, mainly Ru+4 (RuO2), were formed. The stabilized films exhibited high catalytic activity in OER-for the electrochemical process, the onset and η10 overpotentials were approx. 220 and 350 mV, respectively, while for the photoelectrochemical process, the pure photocurrent density of about 160 mA/cm2 mg was achieved at 1.6 V (vs. reversible hydrogen electrode (RHE)). The plasma-deposited RuOX catalyst appears to be an interesting candidate for photoanode material for photoelectrochemical (PEC) water splitting.