Ceria: Relation among thermodynamic,electronic hole and proton properties |
| |
| Institution: | 1. CAS Key Laboratory of Materials for Energy Conversion & Collaborative Innovation Center of Suzhou Nano Science and Technology, University of Science and Technology of China, Hefei 230026, PR China;2. Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621900, PR China;3. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, PR China;1. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China;2. University of Chinese Academy of Sciences, Beijing 100039, China;1. Key Laboratory of Processing and Testing Technology of Glass & Functional Ceramics of Shandong Province, School of Materials Science and Engineering, Qilu University of Technology, Jinan, Shandong 250353, PR China;2. College of Mechanical and Electric Engineering, Hebei Agricultural University, Baoding, Hebei 071001, PR China;1. The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, PR China;2. Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources, Wuhan University of Science and Technology, Wuhan 430081, PR China;3. State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Wuhan 430074, PR China;1. University of Bucharest, Faculty of Chemistry, Department of Organic Chemistry, Biochemistry and Catalysis, B-dul Regina Elisabeta 4-12, Bucharest, Romania;2. Université Lyon 1, CNRS, UMR 5256, IRCELYON, Institut de recherches sur la catalyse et l’environnement de Lyon, 2 avenue Albert Einstein, F-69626 Villeurbanne, France |
| |
| Abstract: | The proton solubility and the hole conductivity of the rare earth doped ceria have been examined in their relations to the thermodynamic properties of doped ceria under the assumption that the hypothetical species, LnOOH and LnOO (Ln = Rare earth), can be regarded as constituents for representing protons and holes in the fluorite lattice. Focus is made on the dopant dependence, the host dependence and the temperature dependence in the rare earth doped zirconia(or ceria) fluorite lattice. The chemical potentials of the rare earth dopant are less stabilized in the ceria-based oxides than in the zirconia-based ones. The proton solubility in the ceria-based, zirconia-based, and ceria–zirconia solid solutions has been well interpreted in terms mainly of the hydroxidation energy and the stabilization energy of LnO1.5 in the fluorite lattice. Since the dopant dependence of the stabilization energy of LnO1.5 is stronger than the hydroxidation energy, the proton solubility becomes high in the smaller dopants. To account for less dopant-dependent behavior in the hole conduction, the peroxidation energy is assumed to have about the same dopant dependence as the stabilization energy. The calculated temperature dependences of proton solubility and hole concentration were compared with available experimental data; it has been suggested that holes and protons in ceria reach to saturation levels with lowering temperature. Some discussions are made on the possible explanation on recently observed anomalous hole conductivity in nano-size Ce0.8Gd0.2O1.9 in terms of plausible effects of miscibility gap, associated Gd enrichment, and simultaneous formation of Ce3+ and holes. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
