| Solid oxide fuel cell (SOFC) is system of electrical power generation with high application value,which has many merits such as high power conversion efficiency,environment friendly,having fewer requests for fuels,needing not noble metal as catalyst and so on. At present,one of the major directions is reducing the operating temperature down to the intermediate/low temperature range below 800℃so that increasing the stabilization,enlarging the range of the materials,and reducing the cost of SOFC,especially being propitious to the commercial application of SOFC in future. One of the key technique issues of SOFC operating at intermediate temperature is the fabrication of high quality electrolyte membrane , the membranes are usually supported by anode supporters. It is very important to investigate the contents,preparing technique and micro structure of the anode supporter in detail,so the main contents of this thesis are the investigations about anode supported for yttria-stabilized- zirconia (YSZ) electrolyte.In this paper,NiO powder synthesized by the precipitation method, YSZ (8 mol% Y2O3-stabilized ZrO2) powders with a average particle size of microns and pore formers were mixed together then pressed into anode supporter. The pore formers'role is to increase the porosity in anode supporter so as to optimize the anode structure and improve the performance of the cell. The different pore formers including flour and active carbon with different weight ratio were added into anode powder,respectively. The effects of different pore formers were studied to determine best pore former and the weight ratio of all pore formers was also optimized.The results suggested that the activated carbon pore former could influence the total sintering shrinkage of anode obviously rather than adjusting the porosity,so active carbon should be used to adjust the sintering shrinkage. Although the variation of the content of flour pore former could hardly affect the sintering shrinkage,it could produce the more porosity and hardly affecting the sintering shrinkage. Based on these conclusions,an idea of composite pore former with flour and activated carbon was presented to adjust both sintering shrinkage and porosity synchronously.The shrinkage curve indicated that the anode-CF composed of NiO,YSZ,flour and activated carbon with weight ratio of 5:5:2.5:0.5 had the nearest total shrinkage (20.4%) to that of YSZ. The anode and electrolyte matched well. The porosity of anode was 34% measured by Archimedes method and it can match the request of SOFC anode supporter well. The YSZ electrolyte was prepared by spinning coating technique on this anode supporter. Sm0.2Ce0.8O1.9 (SDC)-impregnated La0.7Sr0.3MnO3 (LSM) cathodes were deposited on the YSZ films to form the single cells. The cell was tested with air as oxidant and H2 as fuel and the voltage-current curve indicating that the performance of cell was well,there was no concentration polarization in high current density region,so the porosity of anode was in reason. The maximum power densities of the single cell were 688 and 1122 mW/cm2 at 700 and 800℃,respectively.In order to increase the electrochemical or catalytic activity,the anode activated layer (AAL) composed with NiO and YSZ (Tosoh) was prepared between the anode and electrolyte using slurry spin coating method. We studied the influences of the thickness of AAL to the anode supporter and the performance of single cell. AAL increased the electrochemical or catalytic activity of anode,and decreased the impendence between anode and electrolyte. The maximum power density of the single cell with an AAL was 662 mW/cm2 at 700℃,which was much higher than that without AAL about 150%.
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