• Title/Summary/Keyword: electrochemical

Search Result 7,292, Processing Time 0.027 seconds

Applications of Scanning Electrochemical Microscopy

  • Bard, Allen J.;Fan, Fu-Ren F.
    • Analytical Science and Technology
    • /
    • v.8 no.4
    • /
    • pp.1069-1074
    • /
    • 1995
  • The application of scanning electrochemical microscopy to the imaging of surfaces in water and air and to the study of the electrochemistry of single molecules is discussed.

  • PDF

Investigation of Simple Electrochemical Conditions for Generation of Ozonized Water

  • Tanaka, Mutsumi;Kim, Han-Joo;Kim, Tae-Il;Park, Soo-Gil
    • Journal of the Korean Electrochemical Society
    • /
    • v.11 no.3
    • /
    • pp.135-140
    • /
    • 2008
  • An electrochemical generation of ozonized water was investigated by using ${\beta}-PbO_2$ as an anode and tap water as an anolyte. According to the potentiometric ozone detection which utilizes potential differences arisen from a chemical reaction of ozone and iodide, increasing tendency of ozone concentration on electrolysis time could be observed to show the maximum value of 8 ppm at an electrolysis time of 10 min. Ozone could be generated promptly even at an electrolysis time of 10 sec., suggesting great advantages of this electrochemical process in terms of simplicity and readiness that might be applied directly to practical uses including medical and/ or food industries. Influences of electrolysis on the properties and surface conditions of a $PbO_2$ electrode were also discussed from the results of cyclic voltammetry, scanning electron microscope, and X-ray diffractometer.

Consideration on the Non-linearity of Warburg Impedance for Fourier Transform Electrochemical Impedance Spectroscopy

  • Chang, Byoung-Yong
    • Journal of the Korean Electrochemical Society
    • /
    • v.17 no.2
    • /
    • pp.119-123
    • /
    • 2014
  • Here I report on how Fourier Transform Electrochemical Impedance Spectroscopy (FTEIS) overcomes the potential-current linearity problem encountered in the impedance calculation process. FTEIS was first invented to solve the time-related drawback of the conventional impedance technique. The dramatic time reduction of FTEIS enabled the real-time impedance measurement but brought about the linearity problem at the same time. While the conventional method circumvents the problem using the steady-state made by a sufficiently long measurement time, FTEIS cannot because of its real-time function. However, according to the mathematical development reported in this article, the potential step used in FTEIS is proved to avoid the linearity problem. During the step period, the potential and the current are linearized by the electrochemical impedance. Also, Fourier transform of the differentiated potential and current is proved to give the same result of the original ones.

Implementation of Electrochemical Methods for Metrology and Analysis of Nano Electronic Structures of Deep Trench DRAM

  • Zeru, Tadios Tesfu;Schroth, Stephan;Kuecher, Peter
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.12 no.2
    • /
    • pp.219-229
    • /
    • 2012
  • In the course of feasibility study the necessity of implementing electrochemical methods as an inline metrology technique to characterize semiconductor nano structures for a Deep Trench Dynamic Random Access Memory (DT-DRAM) (e.g. ultra shallow junctions USJ) was discussed. Hereby, the state of the art semiconductor technology on the advantages and disadvantages of the most recently used analytical techniques for characterization of nano electronic devices are mentioned. Various electrochemical methods, their measure relationship and correlations to physical quantities are explained. The most important issue of this paper is to prove the novel usefulness of the electrochemical micro cell in the semiconductor industry.

Effects of electrochemical oxidation of carbon fibers on interfacial shear strength using a micro-bond method

  • Kim, Dong-Kyu;An, Kay-Hyeok;Bang, Yun Hyuk;Kwac, Lee-Ku;Oh, Sang-Yub;Kim, Byung-Joo
    • Carbon letters
    • /
    • v.19
    • /
    • pp.32-39
    • /
    • 2016
  • In this work, we studied the effects of electrochemical oxidation treatments of carbon fibers (CFs) on interfacial adhesion between CF and epoxy resin with various current densities. The surface morphologies and properties of the CFs before and after electrochemical-oxidation-treatment were characterized using field emission scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and single-fiber contact angle. The mechanical interfacial shear strength of the CFs/epoxy matrix composites was investigated by using a micro-bond method. From the results, electrochemical oxidation treatment introduced oxygen functional groups and increased roughness on the fiber surface. The mechanical interfacial adhesion strength also showed higher values than that of an untreated CF-reinforced composite.

Electrosynthesis and Electrochemical Properties of Metal Oxide Nano Wire/ P-type Conductive Polymer Composite Film

  • Siadat, S.O. Ranaei
    • Journal of Electrochemical Science and Technology
    • /
    • v.6 no.3
    • /
    • pp.81-87
    • /
    • 2015
  • This study introduces a facile strategy to prepare metal oxide/conducting polymer nanocomposites that may have promising applications in energy storage devices. Ploy aniline/nano wire manganese dioxide (PANI/NwMnO2) was synthesized by cyclic voltammetry on glassy carbon electrode. Morphology and structure of the composite, pure PANI, MnO2 nanowires were fully characterized using XRD and SEM analysis. Electrochemical studies shows excellent synergistic effect between PANI and MnO2 nanowires which results in its capacitance increase and cycle stability against PANI electrode. Specific capacitances of PANI/NwMnO2 and PANI were 456 and 190 F/g respectively. The electrochemical performance of electrodes studied using cyclic voltammetry, Galvanostatic charge/discharge and impedance spectroscopy.

Electrochemically Fabricated Alloys and Semiconductors Containing Indium

  • Chung, Yonghwa;Lee, Chi-Woo
    • Journal of Electrochemical Science and Technology
    • /
    • v.3 no.3
    • /
    • pp.95-115
    • /
    • 2012
  • Although indium (In) is not an abundant element, the use of indium is expected to grow, especially as applied to copper-indium-(gallium)-selenide (CI(G)S) solar cells. In future when CIGS solar cells will be used extensively, the available amount of indium could be a limiting factor, unless a synthetic technique of efficiently utilizing the element is developed. Current vacuum techniques inherently produce a significant loss of In during the synthetic process, while electrodeposition exploits nearly 100% of the In, with little loss of the material. Thus, an electrochemical process will be the method of choice to produce alloys of In once the proper conditions are designed. In this review, we examine the electrochemical processes of electrodeposition in the synthesis of indium alloys. We focus on the conditions under which alloys are electrodeposited and on the factors that can affect the composition or properties of alloys. The knowledge is to facilitate the development of electrochemical means of efficiently using this relatively rare element to synthesize valuable materials, for applications such as solar cells and light-emitting devices.

Micro Electrochemical Machining Characteristics and Shape Memory Effect in Ni-Ti SMA (Ni-Ti SMA의 미세 전해가공특성과 형상기억효과)

  • 김동환;박규열
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.20 no.1
    • /
    • pp.43-49
    • /
    • 2003
  • In this study, micro electrochemical machining method was introduced for accomplishment the fabrication technology of functional parts and smart structures using the Ni-Ti shape memory alloy. From the experimental result, the micro part which has very fine surface could be achieved by use of micro electrochemical process with point electrode method. Concretely, the optimal performance of micro electrochemical process in Ni-Ti SMA was obtained at the condition of approximately 100% of current efficiency and high frequency pulse current. That is, much finer surface integrity and shape memory effect can be obtained at the same condition mentioned above.

Influence of carbon black on electrochemical performance of graphene-based electrode for supercapacitor (슈퍼커패시터를 위한 그래핀 기반 전극의 전기화학적 특성에 대한 카본블랙 도입의 효과)

  • Kim, Ki-Seok;Park, Soo-Jin
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2011.05a
    • /
    • pp.95.1-95.1
    • /
    • 2011
  • In this work, graphene was prepared by modified Hummers method and prepared graphene was applied to electrode materials for supercapacitor. In addition, to enhance the electrochemical performance of graphene, carbon black was deposited onto graphene via chemical reduction. The effect of the carbon black content incorporated on the electrochemical properties of the graphene-based electrodes was investigated. It was found that nano-scaled carbon black aggregates were deposited and dispersed onto the graphene by the chemical reduction of acid treated carbon black and graphite oxide. From the cyclic voltammograms, carbon black-deposited graphene (CB-GR) showed improved electrochemical performance, i.e., current density, quicker response, and better specific capacitance than that of pristine graphene. This indicates that the carbon black deposited onto graphene served as an conductive materials between graphene layers, leading to reducing the contact resistance of graphene and resulted in the increase of the charge transfer between graphene layers by bridge effect.

  • PDF