{"id":{"repo_id":"aachen","oai_identifier":"oai:publications.rwth-aachen.de:59448"},"canonical_url":"https://search.dev.ndltd.org/etd/aachen/oai:publications.rwth-aachen.de:59448","repository":{"repo_id":"aachen","name":"RWTH Aachen University","base_url":"https://publications.rwth-aachen.de/oai2d"},"display":{"title":"Herstellung von dünnen Elektrolytschichten mittels Laserablation und Kathodenzerstäubung für Hochtemperatur-Brennstoffzellen","abstract":"Solid oxide fuel cells (SOFCs) are presently operated at temperatures between 800 and 1000°C. Lowering the operation temperature to 600°C at unchanged power density would increase the durability of the fuel cell stack. Alternative electrolyte materials with a higher electric conductivity and thinner electrolyte films show a possibility to reach this objective. Within this work preferable 1-2 µm thin yttrium oxide stabilised zirconia oxide (YSZ) electrolyte films are deposited using two well known physical vapour deposition (PVD) processes, the pulsed laser deposition (PLD) process and the sputtering process. Alternatively lanthanum gallate films of the system La1-xSrxGa1-yMgyO3-1/2(x+y) (LSGM) are deposited using the PLD process. The films are analysed with regard to the crystal phases, element distribution, crystal growth, morphology and gas tightness. Electrochemical analyses give information about the power density of the fuel cells. A reduction of the YSZ electrolyte film thickness of 7-8 µm to 1.5-2 µm causes an increase of the leakage rate of 1-2 magnitudes. Layer growth models in the literature confirm the morphology of the electrolyte coatings. The typical columnar crystallite structure of PVD films is induced at high process gas pressures. Whereas small pressures promote the growth of dense coatings. By increasing the process gas pressure the transfer of the disordered cubical into the cubical YSZ structure is verified. Partial reduction of the nickel oxide (NiO) grains of the substrate at the film to substrate interface can be proved at little oxygen supply and temperatures > 400°C. The oxygen bound to the NiO diffuse across the YSZ matrix of the substrate into the growing film. Small process gas pressures induce a crystal structure orthogonal to the (100) crystal layer. The concentration ratio of the elements Zr and Y confirm the formation of 8 mol% Y2O3 stabilised ZrO2. No influences of the film thickness on the electric power density of the fuel cells are measured. Amorph deposited LSGM films crystallise after heat treatment in air. At 1200°C only the LSGM phase is formed. Treated films at this temperature are electrochemical characterised afterwards. Ni diffusion from the anode substrate into the electrolyte (12 at%) and further into the cathode (22 at%) cause an electronic short-circuit of the fuel cell after a few minutes. Therefore no current voltage curves are recorded. LSGM is not suitable as an electrolyte material in direct contact with Ni/YSZ anode cermets for solid oxide fuel cell applications.","abstract_html":"Solid oxide fuel cells (SOFCs) are presently operated at temperatures between 800 and 1000°C. Lowering the operation temperature to 600°C at unchanged power density would increase the durability of the fuel cell stack. Alternative electrolyte materials with a higher electric conductivity and thinner electrolyte films show a possibility to reach this objective. Within this work preferable 1-2 µm thin yttrium oxide stabilised zirconia oxide (YSZ) electrolyte films are deposited using two well known physical vapour deposition (PVD) processes, the pulsed laser deposition (PLD) process and the sputtering process. Alternatively lanthanum gallate films of the system La1-xSrxGa1-yMgyO3-1/2(x+y) (LSGM) are deposited using the PLD process. The films are analysed with regard to the crystal phases, element distribution, crystal growth, morphology and gas tightness. Electrochemical analyses give information about the power density of the fuel cells. A reduction of the YSZ electrolyte film thickness of 7-8 µm to 1.5-2 µm causes an increase of the leakage rate of 1-2 magnitudes. Layer growth models in the literature confirm the morphology of the electrolyte coatings. The typical columnar crystallite structure of PVD films is induced at high process gas pressures. Whereas small pressures promote the growth of dense coatings. By increasing the process gas pressure the transfer of the disordered cubical into the cubical YSZ structure is verified. Partial reduction of the nickel oxide (NiO) grains of the substrate at the film to substrate interface can be proved at little oxygen supply and temperatures > 400°C. The oxygen bound to the NiO diffuse across the YSZ matrix of the substrate into the growing film. Small process gas pressures induce a crystal structure orthogonal to the (100) crystal layer. The concentration ratio of the elements Zr and Y confirm the formation of 8 mol% Y2O3 stabilised ZrO2. No influences of the film thickness on the electric power density of the fuel cells are measured. Amorph deposited LSGM films crystallise after heat treatment in air. At 1200°C only the LSGM phase is formed. Treated films at this temperature are electrochemical characterised afterwards. Ni diffusion from the anode substrate into the electrolyte (12 at%) and further into the cathode (22 at%) cause an electronic short-circuit of the fuel cell after a few minutes. Therefore no current voltage curves are recorded. LSGM is not suitable as an electrolyte material in direct contact with Ni/YSZ anode cermets for solid oxide fuel cell applications.","abstract_has_math":false,"creators":["Hobein, Bert"],"institution":"Publikationsserver der RWTH Aachen University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Poprawe, Reinhart"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2003,"date_issued":"2003","date_published":"2003","updated_at":"2026-07-30T19:42:39Z","subjects":["info:eu-repo/classification/ddc/530","Festelektrolyt","Dünne Schicht","Sputtern","Impulslaserbeschichten","Physik","Hochtemperatur-Brennstoffzellen","Elektrolytschichten","Laserablation","Kathodenzerstäubung"],"languages":["ger"],"rights":["info:eu-repo/semantics/openAccess"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-121233%22"],"render_values":[{"text":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-121233%22","href":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-121233%22","code":true}]}]},"links":{"outbound_url":"https://publications.rwth-aachen.de/record/59448","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Poprawe, Reinhart"]},{"key":"dc:creator","label":"Author","values":["Hobein, Bert"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:coverage","label":"Dc Coverage","values":["DE"]},{"key":"dc:date","label":"Dc Date","values":["2003"]},{"key":"dc:publisher","label":"Institution","values":["Publikationsserver der RWTH Aachen University"]},{"key":"dc:relation","label":"Dc Relation","values":["info:eu-repo/semantics/altIdentifier/doi/10.18154/RWTH-CONV-121233","info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-8346"]},{"key":"dc:type","label":"Dc Type","values":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["info:eu-repo/classification/ddc/530","Festelektrolyt","Dünne Schicht","Sputtern","Impulslaserbeschichten","Physik","Hochtemperatur-Brennstoffzellen","Elektrolytschichten","Laserablation","Kathodenzerstäubung"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["ger"]},{"key":"dc:rights","label":"Dc Rights","values":["info:eu-repo/semantics/openAccess"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/record/59448","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-121233%22"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Solid oxide fuel cells (SOFCs) are presently operated at temperatures between 800 and 1000°C. Lowering the operation temperature to 600°C at unchanged power density would increase the durability of the fuel cell stack. Alternative electrolyte materials with a higher electric conductivity and thinner electrolyte films show a possibility to reach this objective. Within this work preferable 1-2 µm thin yttrium oxide stabilised zirconia oxide (YSZ) electrolyte films are deposited using two well known physical vapour deposition (PVD) processes, the pulsed laser deposition (PLD) process and the sputtering process. Alternatively lanthanum gallate films of the system La1-xSrxGa1-yMgyO3-1/2(x+y) (LSGM) are deposited using the PLD process. The films are analysed with regard to the crystal phases, element distribution, crystal growth, morphology and gas tightness. Electrochemical analyses give information about the power density of the fuel cells. A reduction of the YSZ electrolyte film thickness of 7-8 µm to 1.5-2 µm causes an increase of the leakage rate of 1-2 magnitudes. Layer growth models in the literature confirm the morphology of the electrolyte coatings. The typical columnar crystallite structure of PVD films is induced at high process gas pressures. Whereas small pressures promote the growth of dense coatings. By increasing the process gas pressure the transfer of the disordered cubical into the cubical YSZ structure is verified. Partial reduction of the nickel oxide (NiO) grains of the substrate at the film to substrate interface can be proved at little oxygen supply and temperatures > 400°C. The oxygen bound to the NiO diffuse across the YSZ matrix of the substrate into the growing film. Small process gas pressures induce a crystal structure orthogonal to the (100) crystal layer. The concentration ratio of the elements Zr and Y confirm the formation of 8 mol% Y2O3 stabilised ZrO2. No influences of the film thickness on the electric power density of the fuel cells are measured. Amorph deposited LSGM films crystallise after heat treatment in air. At 1200°C only the LSGM phase is formed. Treated films at this temperature are electrochemical characterised afterwards. Ni diffusion from the anode substrate into the electrolyte (12 at%) and further into the cathode (22 at%) cause an electronic short-circuit of the fuel cell after a few minutes. Therefore no current voltage curves are recorded. LSGM is not suitable as an electrolyte material in direct contact with Ni/YSZ anode cermets for solid oxide fuel cell applications."]},{"key":"dc:source","label":"Dc Source","values":["Aachen : Publikationsserver der RWTH Aachen University III, 146 S. : Ill., graph. Darst. (2003). doi:10.18154/RWTH-CONV-121233 = Aachen, Techn. Hochsch., Diss., 2003"]},{"key":"dc:title","label":"Title","values":["Herstellung von dünnen Elektrolytschichten mittels Laserablation und Kathodenzerstäubung für Hochtemperatur-Brennstoffzellen"]}]}],"canonical_facts":{"dc:contributor":["Poprawe, Reinhart"],"dc:coverage":["DE"],"dc:creator":["Hobein, Bert"],"dc:date":["2003"],"dc:description":["Solid oxide fuel cells (SOFCs) are presently operated at temperatures between 800 and 1000°C. Lowering the operation temperature to 600°C at unchanged power density would increase the durability of the fuel cell stack. Alternative electrolyte materials with a higher electric conductivity and thinner electrolyte films show a possibility to reach this objective. Within this work preferable 1-2 µm thin yttrium oxide stabilised zirconia oxide (YSZ) electrolyte films are deposited using two well known physical vapour deposition (PVD) processes, the pulsed laser deposition (PLD) process and the sputtering process. Alternatively lanthanum gallate films of the system La1-xSrxGa1-yMgyO3-1/2(x+y) (LSGM) are deposited using the PLD process. The films are analysed with regard to the crystal phases, element distribution, crystal growth, morphology and gas tightness. Electrochemical analyses give information about the power density of the fuel cells. A reduction of the YSZ electrolyte film thickness of 7-8 µm to 1.5-2 µm causes an increase of the leakage rate of 1-2 magnitudes. Layer growth models in the literature confirm the morphology of the electrolyte coatings. The typical columnar crystallite structure of PVD films is induced at high process gas pressures. Whereas small pressures promote the growth of dense coatings. By increasing the process gas pressure the transfer of the disordered cubical into the cubical YSZ structure is verified. Partial reduction of the nickel oxide (NiO) grains of the substrate at the film to substrate interface can be proved at little oxygen supply and temperatures > 400°C. The oxygen bound to the NiO diffuse across the YSZ matrix of the substrate into the growing film. Small process gas pressures induce a crystal structure orthogonal to the (100) crystal layer. The concentration ratio of the elements Zr and Y confirm the formation of 8 mol% Y2O3 stabilised ZrO2. No influences of the film thickness on the electric power density of the fuel cells are measured. Amorph deposited LSGM films crystallise after heat treatment in air. At 1200°C only the LSGM phase is formed. Treated films at this temperature are electrochemical characterised afterwards. Ni diffusion from the anode substrate into the electrolyte (12 at%) and further into the cathode (22 at%) cause an electronic short-circuit of the fuel cell after a few minutes. Therefore no current voltage curves are recorded. LSGM is not suitable as an electrolyte material in direct contact with Ni/YSZ anode cermets for solid oxide fuel cell applications."],"dc:identifier":["https://publications.rwth-aachen.de/record/59448","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-121233%22"],"dc:language":["ger"],"dc:publisher":["Publikationsserver der RWTH Aachen University"],"dc:relation":["info:eu-repo/semantics/altIdentifier/doi/10.18154/RWTH-CONV-121233","info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-8346"],"dc:rights":["info:eu-repo/semantics/openAccess"],"dc:source":["Aachen : Publikationsserver der RWTH Aachen University III, 146 S. : Ill., graph. Darst. (2003). doi:10.18154/RWTH-CONV-121233 = Aachen, Techn. Hochsch., Diss., 2003"],"dc:subject":["info:eu-repo/classification/ddc/530","Festelektrolyt","Dünne Schicht","Sputtern","Impulslaserbeschichten","Physik","Hochtemperatur-Brennstoffzellen","Elektrolytschichten","Laserablation","Kathodenzerstäubung"],"dc:title":["Herstellung von dünnen Elektrolytschichten mittels Laserablation und Kathodenzerstäubung für Hochtemperatur-Brennstoffzellen"],"dc:type":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]},"updated_at":"2026-07-30T19:42:39Z"}