Low-temperature sintering and enhanced stability of fluorine-modified BaZr0.8Y0.2O3-δ synthesised by a sol-gel alkoxide route
Sol-gel synthesis using alkoxides is employed to obtain fluorine-modified BaZr0.8Y0.2O3-δ nanopowders with Ba excess at 750 °C. Possible effects of F loss at high temperature were limited on densifying at the low temperature of 1200 °C for 4 h on addition of ZnO as sintering agent. The presence of F...
| Authors: | , , , , |
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| Format: | article |
| Status: | Published version |
| Publication Date: | 2023 |
| Country: | España |
| Institution: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repository: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/350349 |
| Online Access: | http://hdl.handle.net/10261/350349 https://api.elsevier.com/content/abstract/scopus_id/85140227465 |
| Access Level: | Open access |
| Keyword: | Barium zirconate BZY Proton-conducting perovskites Protonic ceramic cells Sol-gel |
| Summary: | Sol-gel synthesis using alkoxides is employed to obtain fluorine-modified BaZr0.8Y0.2O3-δ nanopowders with Ba excess at 750 °C. Possible effects of F loss at high temperature were limited on densifying at the low temperature of 1200 °C for 4 h on addition of ZnO as sintering agent. The presence of F in sintered samples was confirmed by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry. XPS and Raman spectroscopy indicated that F doping of BZY inhibits carbonate formation. Conductivity measurements for prolonged periods in wet H2-containing and CO2-containing atmospheres at 500 °C also demonstrated chemical stability. The temperature dependence of the electrical conductivity of sintered samples in wet and dry N2 and O2 indicates that the grain-boundary dominates the electrical behaviour to 500 °C, above which the bulk process dominates. Ionic conduction is prevalent at low temperature, with a transition to a mixed ionic-electronic conducting behaviour at 450 °C. |
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