TY - JOUR

T1 - Femtosecond Laser-Induced Surface Modification of the Electrolyte in Solid Oxide Electrolysis Cells

AU - Marquardt, Tobias

AU - Hollmann, Jan

AU - Gimpel, Thomas

AU - Schade, Wolfgang

AU - Kabelac, Stephan

N1 - Funding information: Acknowledgments: The authors gratefully acknowledge the Energy Research Centre of Lower Saxony (EFZN) for the establishment of a discussion platform within the framework of the Competence Network for Water Electrolysis of Lower Saxony, from which this cooperation emerged. We also thank Kerafol Keramische Folien GmbH for preparing the cells and providing sample electrolytes for preliminary tests. We thank Nicolas Schlüter for providing a calculation tool to optimize the regularization parameter and Nele Geesmann for supporting the performed measurements. The Deutsche Forschungsgemeinschaft (DFG) provided the experimental setup for the electrochemical characterization as part of the major research instrumentation program with contract number INST 187/630-1 FUGG. The publication of this article was funded by the Open Access Fund of the Leibniz Universität Hannover.

PY - 2020/12/12

Y1 - 2020/12/12

N2 - Electrolyte-supported solid oxide cells are often used for steam electrolysis. Advantages are high mechanical stability and a low degradation rate. The aim of this proof of concept study was to use a femtosecond laser to process the electrolyte of an electrolyte-supported solid oxide cell and evaluate the effect of this laser treatment on the electrochemical performance. The femtosecond laser treatment induces a macroscopic and a superimposed microscopic structure. It can be proven that the electrolyte remains gas tight and the electrochemical performance increases independently of the laser parameters. The initial area-specific resistance degradation during a constant current measurement of 200 h was reduced from 7.9% for a non-treated reference cell to 3.2% for one of the laser-treated cells. Based on electrochemical impedance measurements, it was found that the high frequency resistance of the laser-treated cells was reduced by up to 20% with respect to the reference cell. The impedance spectra were evaluated by calculating the distribution of relaxation times, and in advance, a novel approach was used to approximate the gas concentration resistance, which was related to the test setup and not to the cell. It was found that the low frequency polarization resistance was increased for the laser-treated cells. In total, the area-specific resistance of the laser-treated cells was reduced by up to 14%.

AB - Electrolyte-supported solid oxide cells are often used for steam electrolysis. Advantages are high mechanical stability and a low degradation rate. The aim of this proof of concept study was to use a femtosecond laser to process the electrolyte of an electrolyte-supported solid oxide cell and evaluate the effect of this laser treatment on the electrochemical performance. The femtosecond laser treatment induces a macroscopic and a superimposed microscopic structure. It can be proven that the electrolyte remains gas tight and the electrochemical performance increases independently of the laser parameters. The initial area-specific resistance degradation during a constant current measurement of 200 h was reduced from 7.9% for a non-treated reference cell to 3.2% for one of the laser-treated cells. Based on electrochemical impedance measurements, it was found that the high frequency resistance of the laser-treated cells was reduced by up to 20% with respect to the reference cell. The impedance spectra were evaluated by calculating the distribution of relaxation times, and in advance, a novel approach was used to approximate the gas concentration resistance, which was related to the test setup and not to the cell. It was found that the low frequency polarization resistance was increased for the laser-treated cells. In total, the area-specific resistance of the laser-treated cells was reduced by up to 14%.

KW - Distribution of relaxation time

KW - Electrochemical impedance spectroscopy

KW - Femtosecond laser

KW - Solid oxide electrolysis cell

UR - http://www.scopus.com/inward/record.url?scp=85107161901&partnerID=8YFLogxK

U2 - 10.3390/en13246562

DO - 10.3390/en13246562

M3 - Article

VL - 13

JO - Energies

JF - Energies

SN - 1996-1073

IS - 24

M1 - 6562

ER -