| Solid oxide fuel cell (SOFC) is an electrochemical device with all solid-state structure. SOFC can convert the chemical energy in fuels directly to electricity. SOFC, as one of the most attractive energy conversion system, is the focus of global investigation because of its high efficiency, low pollution and fuel flexibility. However, currently, there are some problems to be solved such as the performance of anode catalyst and fabrication on single cell.Combining the state of relative researches and existing problems, the research’s aim of this paper is to improve performance of IT-SOFC single cells. There are two parts studied in the paper:one is simple and efficient method preparation of electrolyte film, and the other is to form catalysts with excellent catalytic properties and good resistance to carbon deposition. The method preparation of electrolyte film is to use electrolyt powders and nitrate solution by spray-coated method and axial compression method. Anode materials were synthesized by polyol method and hard template method. With ethylene glycol as the solvent and reductant, Ni/Cu powder and coating materials related were formed. With activated carbon fiber as hard template, YSZ hollow fibers and coating materials related were formed. The main works and conclusions of this paper are follows:(1) Combining spray-coated method and axial compression method, YSZ film was fabricated. Anode supported planar SOFC single cells were made with NiO-YSZ/YSZ/LSM. The electrochemical performances of the single cells were tested separately using H2as fuel. The results show that the surface of YSZ film was a dense homogeneous surface with a grain size of2～3um. The fracture micrograph shows YSZ film thickness of4-5um. YSZ film was densified after firing at1400℃. Testing temperatures were800℃,750℃,700℃and650℃. With H2as fuel, the open-circuit voltage and the highest power density of single cell were1.0017V,1.0264V,1.0378V,1.0506V and375.471mW·m-2,333.821mW·cm-2,254.828mW·cm-2,186.152mW·cm-2, respectively. This indicates that the performance of cell with single cell was good.(2) The Ni0.8Cu0.2material made by polyol method consisted of nickel and copper and didn’t discover the alloy phase. The particles were small and constant. The microstructure of YSZ powder made by hard template method was hollow fibers structure. Ni0.8Cu0.2can be nicely coated on the surface of YSZ powder and YSZ hollow fibers.(3) The single cells with different anode, which were prepared by the materials above, were tested for electrochemical performances used H2and CH4as fuel separately. The results show that three materials had good catalytic performance and the single cell with Ni0.8Cu0.2coating YSZ hollow fibers anode was the best performance. With CH4as fuel, the Carbon Deposition sTab.ility and of the single cells were tested. After operated continuously10h, the performance of single cells didn’t degrade and the surface of anode didn’t change significantly. There weren’t found carbon deposition and Ni agglomeration. The results indicates that three materials had good resistance to carbon deposition and Ni0.8Cu0.2coating YSZ hollow fibers anode material was better than others. |
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