title: Multi-functional reactively-sputtered copper oxide electrodes for supercapacitor and electro-catalyst in direct methanol fuel cell applications.
abstract: This work reports on the concurrent electrochemical energy storage and conversion characteristics of granular copper oxide electrode films prepared using reactive radio-frequency magnetron sputtering at room temperature under different oxygen environments. The obtained films are characterized in terms of their structural, morphological, and compositional properties. X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscope studies reveal that granular, single-phase Cu2O and CuO can be obtained by controlling the oxygen flow rate. The electrochemical energy storage properties of the films are investigated by carrying out cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy tests. The electrochemical analysis reveals that the Cu2O and CuO electrodes have high specific capacitances of 215 and 272 F/g in 6 M KOH solution with a capacity retention of about 80% and 85% after 3000 cycles, respectively. Cyclic voltammetry and chronoamperometry are used to study the electrochemical energy conversion properties of the films via methanol electro-oxidation. The results show that the Cu2O and CuO electrodes are electro-catalytically active and highly stable.
authors.affiliation: Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
authors.forename: Sambhaji M
authors.initials: SM
authors.lastname: Pawar
authors.affiliation: Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
authors.forename: Jongmin
authors.initials: J
authors.lastname: Kim
authors.affiliation: Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
authors.forename: Akbar I
authors.initials: AI
authors.lastname: Inamdar
authors.affiliation: Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
authors.forename: Hyeonseok
authors.initials: H
authors.lastname: Woo
authors.affiliation: Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
authors.forename: Yongcheol
authors.initials: Y
authors.lastname: Jo
authors.affiliation: Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
authors.forename: Bharati S
authors.initials: BS
authors.lastname: Pawar
authors.affiliation: Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
authors.forename: Sangeun
authors.initials: S
authors.lastname: Cho
authors.affiliation: Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
authors.forename: Hyungsang
authors.initials: H
authors.lastname: Kim
authors.affiliation: Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
authors.forename: Hyunsik
authors.initials: H
authors.lastname: Im