P-Type electronic conduction in CeO2- and LaGaO3-based solid electrolytes

AbstractOxide ion conducting yttria-stabilised zirconia ceramics show the onset of electronic conduction under a small bias voltage. Compositions with a high yttria content undergo a transition from p-type to n-type behavior at voltages in the range 2.4 to 10 V, which also depends on oxygen partial pressure. Surface reactions have a direct influence on bulk electronic conductivities, with possible implications for voltage-induced flash phenomena and resistive switching.

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ELECTRONIC CONDUCTIVITY MEASUREMENTS IN SOLID ELECTROLYTES USING AN ION BLOCKING MICROELECTRODE: NOISE REJECTION BASED ON A MEDIAN FILTER

International Journal of Computational Materials Science and Engineering ◽

10.1142/s2047684113500097 ◽

2013 ◽

Vol 02 (02) ◽

pp. 1350009 ◽

Cited By ~ 1

Author(s):

VEYIS GUNES ◽

JEAN-YVES BOTQUELEN ◽

ODILE BOHNKE

Keyword(s):

Solid Electrolytes ◽

Ionic Conduction ◽

Median Filter ◽

Electronic Conductivity ◽

Conductivity Measurement ◽

Heating System ◽

Electronic Conduction ◽

Oxygen Ion ◽

Noise Rejection

In this paper, a method of electronic conductivity measurement is presented. It combines two well known methods of electrochemistry: cyclic voltammetry and chronoamperometry. This DC technique uses the Hebb–Wagner approach to block ionic conduction (when steady state conditions are reached) and allows electronic conduction of solid electrolytes to be determined. In order to get short diffusion times, a micro contact is used as an ion blocking electrode. However, as the electronic conduction in electrolytes is and should be very low, the current is also very low, typically some tens of nanoamps. Thus, the heating system inevitably generates noise problems that are solved using a median filter. As opposed to other related work, our system allows the determination of the conductivities without any preliminary smoothing or fitting of the curves (since the noise is strongly reduced). Some results with oxygen ion conductors are also given.

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Understanding Metal Propagation in Solid Electrolytes Due to Mixed Ionic–Electronic Conduction

SSRN Electronic Journal ◽

10.2139/ssrn.3834690 ◽

2021 ◽

Author(s):

Qingsong Tu ◽

Tan Shi ◽

Srinath Chakravarthy ◽

Gerbrand Ceder

Keyword(s):

Solid Electrolytes ◽

Electronic Conduction

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Mixed Ionic-Electronic Conduction in N1 Doped Lanthanum Gallate Perovskites

MRS Proceedings ◽

10.1557/proc-496-129 ◽

1997 ◽

Vol 496 ◽

Author(s):

N. J. Long ◽

H. L. Tuller ◽

Lower Hurt ◽

New Zealand

Keyword(s):

Activation Energy ◽

Thermal Expansion ◽

Ionic Conductivity ◽

Electronic Conductivity ◽

Lanthanum Gallate ◽

Electronic Conduction ◽

Similar Magnitude ◽

Ac Impedance Spectroscopy ◽

Dopant Level ◽

P Type

ABSTRACTLanthanum gallate is a promising material for “monolithic” fuel cells or oxygen pumps, i.e. one in which the electrolyte and electrodes are formed from a common phase. We have investigated La1−xSrxGa1–yNiyO3 (LSGNx-y) with x=0.1 and y=0.2 and 0.5 as a potential cathode material for such an electrochemical device. The σ(PO2,T) for LSGN10–20 points to a p-type electronic conductivity at high PO2 and predominantly ionic conductivity at low PO2. LSGN10–50 has an electronic conductivity suitable for SOFC applications of approximately 50 S/cm in air at high temperature. AC impedance spectroscopy on an electron blocking cell of the form M/LSG/LSGN/LSG/M was used to isolate the ionic conductivity in the LSGN10–20 material. The ionic conductivity was found to have a similar magnitude and activation energy to that of undoped LSG material with σi= 0.12 S/cm at 800°C and EA= 1.0 ± 0.1 eV. Thermal expansion measurements on the LSGN materials were characterized as a function of temperature and dopant level and were found to match that of the electrolyte under opeating conditions.

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