%0 Journal Article
%A Kornely, M.
%A Menzler, N. H.
%A Weber, A.
%A Ivers-Tiffée, E.
%T Degradation of a High Performance SOFC Cathode by Cr-Poisoning at OCV-Conditions
%J Fuel cells
%V 13
%N 4
%@ 1615-6846
%C Weinheim
%I Wiley-VCH
%M FZJ-2013-03627
%P 506 - 510
%D 2013
%X In this work we investigate the effect of Cr-poisoning at OCV-condition by means of electrochemical impedance spectroscopy (EIS). The anode-supported cell (ASC) is operated in Cr-free environment for the first 70 h of the cell test at 800 °C supplying air to the cathode and a varying mixture of H2O/H2 to the anode. The performance of the cell is determined by current-voltage (CV) measurement after the start up. After an operating time of 70 h in the absence of chromium species a Cr-source was switched on by passing the oxidant (air) through a Crofer22APU powder bed. In order to determine the degradation caused by Cr-poisoning electrical impedance spectra are collected at every 29 h of operating time. After further 275 h at OCV-condition in the presence of Cr-source another CV-curve is measured. A detailed analysis of the measured impedance spectra by the distribution of relaxation times (DRT) enables a separation of the cathode polarization resistance. During the Cr-free operation the cathode polarization shows a constant value. After the Cr-source is switched on a strong increase of the cathode polarization resistance is observed. This unique result shows clearly that Cr-poisoning of an LSM/8YSZ-cathode already takes place at OCV-condition.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000327706700007
%R 10.1002/fuce.201200182
%U https://juser.fz-juelich.de/record/137158