Journal of the Korean Electrochemical Society (전기화학회지)

The Korean Electrochemical Society (한국전기화학회)
권호 표지
DOI QR코드

DOI QR Code

Basic theory of Dielectric Relaxation Spectroscopy and Studies of Electrolyte Structure

유전체 이완 분광법의 원리 및 이를 이용한 전해액 미시구조 연구

  • 구본협 (대구경북과학기술원에너지공학전공) ;
  • 황순욱 (대구경북과학기술원에너지공학전공) ;
  • 이호춘 (대구경북과학기술원에너지공학전공)
  • Received : 2019.05.10
  • Accepted : 2019.05.21
  • Published : 2019.05.31
Download PDF
⟨ Previous Next ⟩

Abstract

To examine the solution structure of electrolytes, it is very important to understand ion-ion and ion-solvent interactions. In this review, we introduce the basic principle of dielectric relaxation spectroscopy (DRS) and studies of electrolyte structure. DRS is a type of impedance method, which measures the dielectric properties of electrolytes over a high frequency domain at levels of tens of GHz. Therefore, DRS provides information on the different polar chemical species present in the electrolyte, including the type and concentration of free solvents and ion pairs with dipole moments. The information of DRS is complementary to the information of conventional analytical techniques (Infrared/Raman spectroscopy, nuclear magnetic resonance (NMR), etc.) and thus enables a broad understanding of electrolyte structure.

전해질의 미시 구조분석을 위해서는 이온-이온 및 이온-용매 상호작용을 이해하는 것이 매우 중요하다. 이 총설은 유전체 이완 분광법(Dielectric relaxation spectroscopy)의 기본 원리와, 이를 이용한 전해질 구조 연구 사례를 소개하고자 한다. 유전체 이완 분광법은 임피던스법의 일종으로서, 수십 GHz 수준의 높은 주파수 영역에 걸쳐 전해질의 유전 특성을 측정한다. 이를 통해, 유전체 이완 분광법은 전해질 내 존재하는 다양한 극성 화학 종, 즉, 쌍극자 모멘트(Dipole moment)를 갖는 자유 용매(Free solvent) 및 이온쌍(Ion pair)의 종류와 농도에 대한 정보를 제공한다. 유전체 이완 분광법이 제공하는 정보는 기존 분석 기법(적외선 분광법(Infrared), 라만 분광법(Raman) 및 핵자기 공명 분광법(Nuclear magnetic resonance) 등)이 제공하는 정보들과 상호보완적 관계에 있으며, 이러한 종합적 분석을 통해 전해질 구조에 관한 깊은 이해가 가능하다.

Keywords

JHHHB@_2019_v22n2_53_f0001.png 이미지

Fig. 1. Parallel plate capacitor with direct current (DC) voltage source.

JHHHB@_2019_v22n2_53_f0002.png 이미지

Fig. 2. Parallel plate capacitor with alternating current(AC) voltage source.

JHHHB@_2019_v22n2_53_f0003.png 이미지

Fig. 3. Frequency response of dielectric mechanisms.

JHHHB@_2019_v22n2_53_f0004.png 이미지

Fig. 4. Dipole rotation in electric field.

JHHHB@_2019_v22n2_53_f0005.png 이미지

Fig. 5. Permittivity, ε′ (v) spectra and dielectric loss, ε″ (v) spectra of water at 25oC.

JHHHB@_2019_v22n2_53_f0006.png 이미지

Fig. 6. Total permittivity, η″ (v) , permittivity, ε′ (v) spectra, and dielectric loss, ε″ (v) spectra of 0.1 M Fe(ClO4)2 at 25oC. The slashed areas show the contributions of the ion pair (IP) and free water molecule relaxation process to ε″ (v).

JHHHB@_2019_v22n2_53_f0007.png 이미지

Fig. 7. Permittivity, ε′ (v) , and dielectric loss, ε″ (v) of 1 M LiBF4-PC compared with the spectrum calculated with Debye equation. The slashed areas show the contributions of the SIP, CIP and free PC solvents (PC and PC') relaxation process to ε″ (v).

Table 1. Possible ionic species in non-aqueous system, and their activity for Raman spectroscopy and DRS.

JHHHB@_2019_v22n2_53_t0001.png 이미지

References

  1. J. O. M. Bockris, A. K. Reddy and M. Gamboa-Aldeco, "Modern Electrochemistry: An Introduction to an Interdisciplinary Area", Plenum Press, New York (1998).
  2. J. M. Barthel, H. Krienke and W. Kunz, "Physical Chemistry of Electrolyte Solutions: Modern Aspects", Springer, New York (1998).
  3. R. Buchner, G. T. Hefter and P. M. May, 'Dielectric Relaxation of Aqueous NaCl Solutions', J. Phys. Chem. A, 103, 1-9 (1999). https://doi.org/10.1021/jp982977k
  4. F. H. Stillinger Jr and R. Lovett, 'Ion-Pair Theory of Concentrated Electrolytes. I. Basic Concepts', J. Chem. Phys., 48, 3858-3868 (1968). https://doi.org/10.1063/1.1669709
  5. C. Bættcher, "Theory of Electric Polarization. Vol. 1: Dielectric in Static Fields", Elsevier, New York (1973).
  6. Von C. F. J. Bottcher and P. Bordewijk, "Theory of Electric Polarization. Vol. 11. Dielectrics in Time-Dependent Fields", Oxford, New York (1978).
  7. A. Schonhals and F. Kremer, "Broadband Dielectric Spectroscopy", Springer, Berlin (2012).
  8. R. Buchner and G. Hefter, 'Interactions and Dynamics in Electrolyte Solutions by Dielectric Spectroscopy', Phys. Chem. Chem. Phys., 11, 8984-8999 (2009). https://doi.org/10.1039/b906555p
  9. E. Cavell, P. Knight and M. Sheikh, 'Dielectric Relaxation in Non Aqueous Solutions. Part 2.-Solutions of Tri (n-Butyl) Ammonium Picrate and Iodide in Polar Solvents', J. Chem. Soc. Faraday Trans., 67, 2225-2233 (1971). https://doi.org/10.1039/TF9716702225
  10. Y. Yamada, K. Furukawa, K. Sodeyama, K. Kikuchi, M. Yaegashi, Y. Tateyama and A. Yamada, 'Unusual Stability of Acetonitrile-Based Superconcentrated Electrolytes for Fast-Charging Lithium-Ion Batteries', J. Am. Chem. Soc., 136, 5039-5046 (2014). https://doi.org/10.1021/ja412807w
  11. K. Yoshida, M. Nakamura, Y. Kazue, N. Tachikawa, S. Tsuzuki, S. Seki, K. Dokko and M. Watanabe, 'Oxidative-Stability Enhancement and Charge Transport Mechanism in Glyme-Lithium Salt Equimolar Complexes', J. Am. Chem. Soc., 133, 13121-13129 (2011). https://doi.org/10.1021/ja203983r
  12. T. Doi, Y. Shimizu, M. Hashinokuchi and M. Inaba, '$LiBF_4$-Based Concentrated Electrolyte Solutions for Suppression of Electrolyte Decomposition and Rapid Lithium-Ion Transfer at $LiNi_{0.5}Mn_{1.5}O_4$/Electrolyte Interface', J Electrochem. Soc., 163, A2211-A2215 (2016). https://doi.org/10.1149/2.0331610jes
  13. T. Doi, R. Masuhara, M. Hashinokuchi, Y. Shimizu and M. Inaba, 'Concentrated $LiPF_6/PC$ Electrolyte Solutions for 5-V $LiNi_{0.5}Mn_{1.5}O_4$ Positive Electrode in Lithium-Ion Batteries', Electrochim. Acta, 209, 219-224 (2016). https://doi.org/10.1016/j.electacta.2016.05.062
  14. R. Buchner, G. Hefter, P. M. May and P. Sipos, 'Dielectric Relaxation of Dilute Aqueous NaOH, $NaAl(OH)_4$, and $NaB(OH)_4$', J. Phys. Chem. B, 103, 11186-11190 (1999). https://doi.org/10.1021/jp992551l
  15. S. Hwang, D.-H. Kim, J. H. Shin, J. E. Jang, K. H. Ahn, C. Lee and H. Lee, 'Ionic Conduction and Solution Structure in LiPF6 and LiBF4 Propylene Carbonate Electrolytes', J. Phys. Chem. C, 122, 19438-19446 (2018). https://doi.org/10.1021/acs.jpcc.8b06035
  16. J. Barthel, M. Kleebauer and R. Buchner, 'Dielectric Relaxation of Electrolyte Solutions in Acetonitrile', J. Solution Chem., 24, 1-17 (1995). https://doi.org/10.1007/BF00973045
  17. P. Eberspacher, E. Wismeth, R. Buchner and J. Barthel, 'Ion Association of Alkaline and Alkaline-Earth Metal Perchlorates in Acetonitrile', J. Mol. Liq., 129, 3-12 (2006). https://doi.org/10.1016/j.molliq.2006.08.007
  18. A. Placzek, G. Hefter, H. M. Rahman and R. Buchner, 'Dielectric Relaxation Study of the Ion Solvation and Association of $NaCF_3SO_3$, $Mg(CF_3SO_3)_2$, and $Ba(ClO_4)_2$ in N, N-Dimethylformamide', J. Phys. Chem. B, 115, 2234-2242 (2011). https://doi.org/10.1021/jp1116307
  19. B. Wurm, M. Münsterer, J. Richardi, R. Buchner and J. Barthel, 'Ion Association and Solvation of Perchlorate Salts in N, N-Dimethylformamide and N, N-Dimethylacetamide: A Dielectric Relaxation Study', J. Mol. Liq., 119, 97-106 (2005). https://doi.org/10.1016/j.molliq.2004.10.015
  20. N. Ottosson, J. Hunger and H. J. Bakker, 'Effect of Cations on the Hydrated Proton', J. Am. Chem. Soc., 136, 12808-12811 (2014). https://doi.org/10.1021/ja503635j
  21. N. Agmon, 'The Grotthuss Mechanism', Chem. Phys. Lett., 244, 456-462 (1995). https://doi.org/10.1016/0009-2614(95)00905-J
  22. S. Cukierman, 'Et tu, Grotthuss! and Other Unfinished Stories', Biochim. Biophys. Acta, 1757, 876-885 (2006). https://doi.org/10.1016/j.bbabio.2005.12.001
  23. R. Buchner, T. Chen and G. Hefter, 'Complexity in "Simple" Electrolyte Solutions: Ion Pairing in $MgSO_4(aq)$', J. Phys. Chem. B, 108, 2365-2375 (2004). https://doi.org/10.1021/jp034870p
  24. A. Tromans, P. M. May, G. Hefter, T. Sato and R. Buchner, 'Ion Pairing and Solvent Relaxation Processes in Aqueous Solutions of Sodium Malonate and Sodium Succinate', J. Phys. Chem. B, 108, 13789-13795 (2004). https://doi.org/10.1021/jp048575w