| Fuel cell is an advanced technology which is advantageous to the environmental protection, and it is regarded as the green energy transformation technology for the 21st century. However, solid oxide fuel cell (SOFC) is one kind of highest energy conversion efficiency in Fuel cell. Moreover, it can use various fuels like:methane, coal gas, methyl alcohol, ethyl alcohol, petroleum liquid gas and so on, do not need the special fuel depuration installment, also do not built new hydrogenation station look like the polymer electrolyte fuel cell. Therefore, SOFC is quite easy to promote, and the operating cost is low, very suitably in our country's national condition. And it is of advantage to improve energy structure and raise the energy use factor. The development of intermediate temperature solid oxide fuel cell (IT-SOFC) expanded in the connector and the seal material choice scope greatly in traditional SOFC, reduced the material fabrication and the cell manufacture cost greatly. However reduction of the SOFC operating temperature will receive new challenge in the performance of key material and the fabrication technology, and the electrolyte thin film technology and the fabricate electrolyte and the electrode material with high performance are the keys to reduces the SOFC operating temperature and manufacture SOFC with high performance.In this thesis we fabricate Sr and Mg doped lanthallum gallate (LSGM) electrolyte powder and Sr and Mn doped LaCrO3 anode supports which have high catalytic activity. The phase formation, microstructure and the performance of them were tested by X-ray diffraction (XRD), scanning electron microscopy (SEM), electronic differential system (EDS) and four-probe method and so on. Aiming at developing high performance planar anode-supported IT-SOFC. It is found that The LSCM anode films which mix with LSCM precursor material which synthesized by Glycine nitrate Process (GNP) and 8wt.%amylum sintering at 1350℃for 5 hours meets a need of anode support for IT-SOFC. LSGM powder sintering at 1400℃for 20 hours obtained single perovskite phase LSGM which is suitable for use in fabricating targets for magnetron sputtering and in the electrolyte slurry for spin coating method. And they are suitable for fabricating dense electrolyte film.In addition, this paper focuses on two kinds of fabrication methods of film electrolyte, namely radio-frequency (RF) magnetron sputtering and spin coating method.We use RF magnetron sputtering fabricated electrolyte thin film. The effect of different sputtering condition, like sputtering power density, substrate temperature and Ar gas pressure and so on, on the phase formation, structure, deposition rate and microstructure in the film obtained was estimated, and analyzed these factors on the impact of properties of thin films. It is showed that the thin electrolyte membrane annealing at 1000℃for 2 hours can obtained the best performance. Which thickness is about 8um, fabricated in following sputtering condition:the power density is 7.8 W/cm2, substrate temperature is 300℃at the same time and the Ar pressure is 2Pa, after 12 hours of sputtering deposition.In addition, we studied spin coating process for fabricating electrolyte thin film. The effect of various binder and modifier as well as their dosage under a certain rotate speed of spin coater on the performance of LSGM electrolyte film was analyzed. X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), Electronic Differential System (EDS) and other means were used to evaluate the quality of the film. It is showed that the electrolyte films fabricated with the slurry consisted of LSGM powder,3wt.% ethyl cellulose,5wt.% terpineol and ethanol by spin-coating process under operating parameters of 3200r/min and 40s, sintering at 1450℃under 8 hours in Muffle furnace, with thickness about 30μm, and they were well adhered to the anode substrates, and have good density. |
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