Decrease in the double layer capacitance by faradaic current

• Aoki Koichi Jeremiah

• Chen Jingyuan

• Zeng Xiangdong

• Wang Zhaohao

抄録

This study describes the reverse of the well-known double layer effects on charge transfer kinetics in the relationship between a cause and an effect. The reversible redox reaction of a ferrocenyl derivative decreased the capacitive values of the double layer impedance up to negative values, corresponding to an inductive component. This observation was disclosed by the subtraction of the real admittance from the imaginary admittance, which can extract the net double layer capacitance from the Warburg impedance. The inductance-like behavior is caused due to two reasons: (i) the double layer capacitance in the polarized potential domain is determined by the low concentrations of the fieldoriented solvent dipoles that are considered as the conventionally employed redox concentrations and (ii) the double layer capacitance is caused by the orientation of the dipoles in the same direction as that of the electric field, whereas the redox reaction generates charge in the direction opposite to the field. The faradaic effect was demonstrated via the ac-impedance data obtained for the ferrocenyl compound in a KCl solution in the unpolarized potential domain between 1 Hz and 3 kHz frequency. The negative admittance was proportional to the frequency. The theory of negative capacitance was presented by combining the mirror-image surface charge with the Nernst equation.

収録刊行物

• RSC Advances

  RSC Advances (7), 22501-22509, 2017-07

  Royal Society of Chemistry

キーワード

• negative capacitance
• interplay of Faradaic reaction and double layer capacitance
• redox reaction of ferrocenyl derivative
• ac impedance with frequency-dependence

詳細情報

• CRID: 1570009752921290368
• NII論文ID: 120006324023
• ISSN: 20462069
• Web Site: http://hdl.handle.net/10098/10219
• 本文言語コード: en
• データソース種別:
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