Title data
Donker, Nils ; Ruchets, Anastasiya ; Schönauer-Kamin, Daniela ; Zosel, Jens ; Guth, Ulrich ; Moos, Ralf:
Pulse polarization measurements on the system Pt|YSZ by varying the polarization voltage.
2019
Event: 7th Regional Symposium on Electrochemistry of South-East Europe
, 27.-30. Mai 2019
, Split, Croatia.
(Conference item: Conference
,
Speech
)
Abstract in another language
Most sensors for nitrogen oxides (NOx; NO and NO2) are based on potentiometric (equilibrium and non-equilibrium), amperometric, or impedancemetric principles to detect the concentration of NOx in the atmosphere. All these methods have in common that they reach a steady state value at a constant atmosphere after certain time. In contrast, the pulsed polarization method is a dynamic method and it utilizes the well-known Pt|YSZ-system. Platinum electrodes are screen-printed on both sides of a YSZ substrate for this purpose. Both sensor electrodes are exposed to the same gas atmosphere at the same temperature. Therefore, a potentiometric measurement would result in the voltage difference 0 V. To receive a signal, the sensor is brought out of its equilibrium state. In order to do this, the sensor is polarized with the polarization voltage Upol for a duration t_pol. The sensor then automatically discharges after the voltage source has been removed. It could be shown that the self-discharge accelerates strongly with increasing NOx concentration. After the discharge time tdischarge, the sensor is polarized again for the duration tpol, but with the opposite sign -Upol. Such a cycle with alternating polarization and intermediate discharge is schematically shown in Fig. 1a. A sensor signal can be generated on the basis of the voltage values at a defined point in time in the cycle. Examples for such points in time are schematically marked as U_signal1 and U_signal2. In the case of a perfectly symmetrical sensor design, the magnitude of these voltages is the same in terms of measurement accuracy. In this study, the operation of the pulse polarization with different polarization voltages shall be shown. It can be expected that the voltage and the resulting reactions will have a significant influence on the sensor signal. Some results measured at various polarization voltages (100, 500 and 1000 mV) are shown in Fig. 1b. Here, the voltages 3 seconds after the beginning of each cycle are displayed.
Further data
Item Type: | Conference item (Speech) |
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Refereed: | Yes |
Institutions of the University: | Faculties > Faculty of Engineering Science Faculties > Faculty of Engineering Science > Chair Functional Materials > Chair Functional Materials - Univ.-Prof. Dr.-Ing. Ralf Moos Profile Fields > Advanced Fields > Advanced Materials Research Institutions > Research Centres > Bayreuth Center for Material Science and Engineering - BayMAT Faculties Faculties > Faculty of Engineering Science > Chair Functional Materials Profile Fields Profile Fields > Advanced Fields Research Institutions Research Institutions > Research Centres |
Result of work at the UBT: | Yes |
DDC Subjects: | 600 Technology, medicine, applied sciences > 620 Engineering |
Date Deposited: | 12 Jun 2019 06:51 |
Last Modified: | 12 Jun 2019 06:51 |
URI: | https://eref.uni-bayreuth.de/id/eprint/49459 |