Journal of Materials Science

, Volume 54, Issue 9, pp 7072–7077 | Cite as

Direct measurement of “ready-made” cations in a Ge2Sb3.4Te6.2 film

  • Yusuke Imanishi
  • Toshihiro NakaokaEmail author
Electronic materials


We have successfully observed Faradaic current in cyclic voltammetry of an amorphous Ge2Sb3.4Te6.2 film with Ag electrodes. The Faradaic current peak was attributed to a non-reversible redox process limited by diffusion of Ag cations. The Ag cations can be generated by anodic dissolution under applied bias voltage or may exist before the voltage application as “ready-made” ions. The cyclic voltammetry demonstrated the existence of ready-made Ag cations. The concentration of the ready-made cations was 0.008 mol/cm3, which was about one-tenth of the cations formed by a voltage sweep at 3.6 V/s, and was about one-hundredth of those formed at 0.3 V/s.



This work was supported in part by MEXT KAKENHI Grant Numbers 17K18887 and 18H01480, and Sophia University Special Grant for Academic Research. Part of this work was conducted at Advanced Characterization Nanotechnology Platform of the University of Tokyo, supported by “Nanotechnology Platform” of MEXT.


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Faculty of Science and TechnologySophia UniversityTokyoJapan

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