Electrochemistry
Online ISSN : 2186-2451
Print ISSN : 1344-3542
ISSN-L : 1344-3542
Volume 80 , Issue 11
Showing 1-25 articles out of 25 articles from the selected issue
Preface
Communications
  • Hiroshi SADAMURA, Noriko SUZUKI, Yasushi KANZAKI
    2012 Volume 80 Issue 11 Pages 876-878
    Published: November 05, 2012
    Released: November 05, 2012
    JOURNALS OPEN ACCESS
    The endoscope is one of the most extensively used medical devices. Endoscopes are deterged with extreme care because they are inserted directly in the body. Electrochemical disinfection using a palladium-coated carbon cloth electrode was applied to deterge a rod-shaped tool as a potential endoscope-deterging method because it required no toxic agent, did not cause secondary pollution, and provided an eco-friendly disinfection system. The anodic polarization of palladium in an NaCl-containing solution led to the effective generation of disinfective ClO and the simultaneous gas evolution caused natural convection that increased the disinfection efficacy. Electrochemical degreasing could also be attained by alternating between positive and negative electrode polarities.
    Download PDF (664K)
  • Chihiro OBAYASHI, Mitsuru ISHIZAKA, Takayoshi KONISHI, Hirohisa YAMADA ...
    2012 Volume 80 Issue 11 Pages 879-882
    Published: November 05, 2012
    Released: November 05, 2012
    JOURNALS OPEN ACCESS
    Layered Manganese and aluminum double hydroxides (Mn-Al LDH) were electrochemically synthesized on a Ni, or a Pt substrate by galvanostatic electrochemical reduction of Mn(NO3)2 and Al(NO3)3 aqueous solutions mixtures. The obtained XRD data indicated that the interlayer spacing of the Mn-Al LDH was 0.87 nm and was in good agreement with that reported for NO3/Mn-Al LDH. The contents of trivalent cation, Al3+, in the products were almost identical to those in the corresponding electrolyte solutions. During electrochemical oxidation and reduction of NO3/Mn-Al LDH precipitated from a Mn(NO3)2 and Al(NO3)3 aqueous solutions 3:1 mixture in a 2 mol dm−3 KOH solution, Al contents in the NO3/Mn-Al LDH deviated products decreased by ca. 0.2. Although the dissolution of Al3+ in the LDHs occurred at the first electrochemical oxidation in a 2 mol dm−3 KOH solution, reversible redox peaks were observed at around −0.2 V vs. Hg/HgO after 2nd cycle of CVs.
    Download PDF (1408K)
  • Junji SUZUKI, Naoyuki ISHIDA, Masumi FUKUMA, Takayuki UCHIDA
    2012 Volume 80 Issue 11 Pages 883-885
    Published: November 05, 2012
    Released: November 05, 2012
    JOURNALS OPEN ACCESS
    EDLC and Li-ion Capacitor are attractive devices for accumulation of electricity. Their electrodes are made mainly from activated carbon. SATO-KOMUSHO Corporation has made activated carbon from used-cotton-towels. If it could be used for their electrode material, it would be good for the local industry. Hence, we have researched the possibility of carbonized used-cotton-towels as an electrode material. This research investigated an optimum compounding ratio by changing the ratio of a binder and conductive additives in order to obtain an essential capacity of the carbon material. Its capacity was ca. 100 F g−1 and proved to be as large as that of current commercial electrode.
    Download PDF (855K)
Articles
  • Junichi OGAWA, Satoshi NISHIKAWA, Toshikazu HASEGAWA, Shogo MORI
    2012 Volume 80 Issue 11 Pages 886-890
    Published: November 05, 2012
    Released: November 05, 2012
    JOURNALS OPEN ACCESS
    In order to apply stepped light-induced transient measurements of photocurrent and voltage (SLIM-PCV) to obtain electron diffusion coefficients and lifetimes in dye-sensitized solar cells (DSCs), electron density gradient in the electrode must be small so that the density can be approximated as a constant value. In this paper we prepared DSCs with two different dyes with various thicknesses of TiO2 electrodes, and apply SLIM-PCV with two different wavelengths of the lasers. Required conditions of the DSCs for the measurements and methods to check the validity of the measurements are discussed.
    Download PDF (671K)
  • Takeshi YANE, Akira KOYAMA, Kenta HIRAMATSU, Yoshitaka ISOGAI, Keigo I ...
    2012 Volume 80 Issue 11 Pages 891-897
    Published: November 05, 2012
    Released: November 05, 2012
    JOURNALS OPEN ACCESS
    We have designed an electrodeposition system employing multiple rotating disc electrodes (RDE) in a single electrochemical bath, with an aim to develop a mean to obtain homogeneous zinc oxide (ZnO) thin films with a high reproducibility, as the reaction is known to be strongly limited by mass transport. Substrates such as F-doped SnO2 (FTO) coated glass having no electric conduction on the back side were furnished into a geometry of RDEs employing conductive and insulating tapes. The shape of the active electrode area was determined through tests. Also, the influence of the position of the RDE in the electrochemical bath was tested. Having confirmed that neighboring RDEs do not interfere each other, eight RDEs were placed like a roulette in a single electrolytic bath. The resulting eight ZnO samples electrodeposited by using the eight RDE system were almost identical with the standard deviation of less than 0.3% for their thickness.
    Download PDF (1534K)
  • Hidenobu SHIROISHI, Shinjiro HAYASHI, Minoru YONEKAWA, Ryo SHOJI, Itar ...
    2012 Volume 80 Issue 11 Pages 898-903
    Published: November 05, 2012
    Released: November 05, 2012
    JOURNALS OPEN ACCESS
    An electrochemical recycling process of the noble metal such as Pt and Ru from the membrane electrode assemblies (MEAs) in fuel cells was investigated for the environment-friendly process without aqua regia. The dissolution rate of Pt in HCl solution was about 50 times as fast as those in H2SO4 and HClO4 solutions. The Pt dissolution rate increased linearly with HCl concentration. Pt dissolution under fluctuating potential using saw-tooth wave is 15 times faster than that under constant potentials. The electrochemical dissolution method can also be applied to the dissolution of Pt and Ru in the PtRu catalysts. The chemical methods using aqua regia, HCl-H2O2 mixed solution, and HCl only were also investigated for the comparison as the electrochemical methods. The Pt dissolution rate decreased according to the order of aqua regia > 11.3 M HCl-0.36 M H2O2 > 1 M HCl-10.3 M H2O2 > 1 M HCl. The vaporization rate of oxidants (NOCl and Cl2) from aqua regia at 333 K was 40 times as fast as that at 298 K by a spectrochemical method.
    Download PDF (1076K)
  • Katsuhiko TSUNASHIMA, Masahiro FUKUSHIMA, Masahiko MATSUMIYA
    2012 Volume 80 Issue 11 Pages 904-906
    Published: November 05, 2012
    Released: November 05, 2012
    JOURNALS OPEN ACCESS
    Novel room-temperature ionic liquids based on trialkylphosphonium cations and their physicochemical characterizations are presented in this report. It was found that ionic liquids based on trialkylphosphonium cations together with bis(trifluoromethylsulfonyl)amide anion were lower melting, lower viscous and more conductive than the corresponding trialkylammonium ionic liquids. Particularly, triethylphosphonium bis(trifluoromethylsulfonyl)amide exhibited the lowest viscosity and highest conductivity in the trialkylphosphonium-based ionic liquids. The protic ionic liquid electrolyte based on triethylphosphonium bis(trifluoromethylsulfonyl)amide also showed relatively high conductivity when compared to the corresponding ammonium ionic liquid electrolyte.
    Download PDF (473K)
Technological Report
  • Dahai XIA, Jiangbo SHI, Wenqi GONG, Rongji ZHOU, Zhiming GAO, Jihui WA ...
    2012 Volume 80 Issue 11 Pages 907-912
    Published: November 05, 2012
    Released: November 05, 2012
    JOURNALS OPEN ACCESS
    The corrosion types of Q235 carbon steel and nuclear grade 304 stainless steel (304 NG SS) in different solutions are investigated by electrochemical noise (EN) technique. EN data are analyzed by using phase space reconstruction theory. With the obtained correlation dimension from the phase space reconstruction, the chaotic behavior of EN is quantitatively evaluated. It is concluded that local corrosion shows a higher correlation dimension while passivation shows a lower correlation dimension. We propose that the correlation dimension increases with the complexity and uncertainty of the signals from passivation to local corrosion, which is the physical meaning of correlation dimension for EN.
    Download PDF (1718K)
Notes
Topic
 
Salon
 
 
feedback
Top