Evaluation of the electrical capacitance of M,O2/O2− interfaces (M=Pt, Au, Pd, In2O3; O2− = zirconia based electrolyte) exhibiting constant phase element behavior

Abstract

Abstract. The behavior of the electrode systems M,O2/O 2 (M = porous Pd, Pt, A and den~ ln20~ ; 0 2. = ZrO2-based single-crystal solid electrolyte) was studied by means of impedance measurements. The examination of the Pt,O2/O 2 electrode system showed that the constant phase element (CPE) can be attributed to a nonuniform distribution of current at the electrode surface. It was observed that the CPE parameters n and B in the expression YCPE = B ( j03 )" may be related by B = (Cd0" (R~2) "~ ,where Cd~ is the double layer capacitance and Rn the resistance of the electrolyte in the cell. Then, Cj~ of the electrode -electrolyte interface could be determined. The specific Cd~ of the oxidized noble metals and india electrodes is nearly one order of magnitude lower than Ca~ of the electrodes in the metallic state. The Cd~ value of all the electrodes studied depends little or is independent of temperature and oxygen pressure. It is concluded that the Helmholtz model of double layer structure does not contradict the Cjj behavior.

All-solid-state electric-double-layer transistor based on oxide ion migration in Gd-doped CeO2 on SrTiO3 single crystal

“…The Pt/GDC interface of the STO-Pt cell had extremely high capacitance, averaging 252 lF cm À2 , which is relatively close to the 150 lF cm À2 predicted by Kuzin et al, who investigated the EDL capacitance of bulk oxide ion conductors with porous metal and oxide electrodes. 17 The difference between the capacitance at the Pt/GDC interface of the Pt-Pt cell, averaging 247 lF cm À2 , and that at the Pt/GDC interface of the STO-Pt cell, 252 lF cm À2 , was not significant, indicating that the orientation of the preferential growth of GDC had little effect on the capacitance. The capacitance at the GDC/STO interface, averaging 14 lF cm À2 , was higher than that of a microporous SiO 2 EDLT using proton migration, 2.14 lF cm À2 , 8 and comparable to that of an ionic-liquid EDLT, 13 lF cm À2 .…”