Conformal deposition of RuO2 on Cu via a galvanic cementation reaction

Chun Lin, Shih Cheng Chou, Kuang Chih Tso, Yi Chieh Hsieh, Ting Shan Chan, Po Chun Chen, Junichi Koike, Pu Wei Wu

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)


We develop a seedless wet chemical process to deposit uniform RuO2 on a Cu substrate. Our approach entails the synthesis of volatile RuO4 colloids in a pH 9 aqueous solution from the oxidation of RuCl5 2− by ClO, followed by a galvanic cementation reaction in which the Cu undergoes a mild oxidation in conjunction with the reduction of RuO4 to produce a dense and conformal RuO2 thin film on the Cu surface. The nature for the chemical reactions and constituents involved are investigated by UV-Vis, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. Both as-deposited and annealed RuO2 films are characterized by scanning electron microscope and X-ray diffractometer. The as-deposited RuO2 film, with a thickness of 199 nm, reveals an amorphous structure and after an Ar annealing, becomes crystalline in rutile phase. In between the RuO2 and Cu, there are presence of CuO from the displacement cementation reaction, and Cu2O from the parasitic Cu corrosion as expected from the Pourbaix diagram. These Cu oxides, with a thickness of 330 nm, provide sufficient adhesive bonding between RuO2 and Cu.

Original languageEnglish
Pages (from-to)D476-D482
JournalJournal of the Electrochemical Society
Issue number10
Publication statusPublished - 2019


Dive into the research topics of 'Conformal deposition of RuO2 on Cu via a galvanic cementation reaction'. Together they form a unique fingerprint.

Cite this