| A fuel cell is an energy conversion device with a high efficiency and a low pollution. Different from the traditional cells that can only reserve energy, it generates electricity from fuels such as hydrogen, natural gas and other hydrocarbons. The fuel cell is also called a cell because it is composed of electrolyte, anode and cathode, which are the same for a normal cell. The electrolyte is sandwiched by the two electrodes. The fuel cell is also different from the traditional power generation methods. Because it is not limited by the Carnot cycle, fuel cell has advantages of higher energy conversion efficiency and lower polluted gases emission over the traditional generator. Recently with the natural resource exhaustion and environment deterioration, developing efficient and environmental friendly energy techniques is necessary. Since fuel cell just matches such requirements, it attracts the interests all over the world.As the fourth generation fuel cell, a clean energy conversion device,SOFC (Solid Oxide Fuel Cell) has many outstanding advantages, which is better than other fuel cells. Firstly, equipped with all solid components, it eliminates the problems that liquid electrolyte fuel cell faces, such as corrosion and leakage of liquid electrolytes. Secondly, operating at high temperatures, its electrode reaction is so fast that it is unnecessary to use noble metals as electrodes. Thus the cost of the cells can be minimized. At the same time, the high quality heat it emits can be fully used. The overall energy conversion efficiency of the thermal-electric system can be added up to 80%. The most outstanding advantage of SOFC is that it uses a large scale of fuels, from the hydrogen, carbon monoxide to the natural gas or even other combustive gases. Currently the main difficulty that the SOFC faces is the problem caused by high temperature and the ceramic components'match..Decreasing the operating temperature of SOFCs down to intermediate range(500-800℃),which is desirable due to important economical and technological advantages, As the key component of SOFC, anode plays a very important role in the performance of the whole cell. The anode material's properties and the anodic microstructure are determined by the anodic reaction mechanism. To improve the anode performance, proper materials should be selected while perfect preparation technique should be employed at the same time.At present,ABO3 oxides doped with rare element in A sites become one of hot spots .La doped SrTiO3,a mixed conductor,shows high conductivity high,good chemical and good thermal stability,This makes it potentially be used as anode materials for solid oxide fuel cells.Doped SrTIiO3 powders is usually made by solid-state reaction.The powders is coarse size,poor activity and a high sintering temperature manufactured by the solid-state reaction.In this dissertation,the introduction of modern methods of wet chemical sol-gel method (sol-gelmethod) powders were prepared to study the powder phase composition, morphology, particle size and sintering activity,and the properties of the sintered specimen as-prepared were also tested.The results showed the powders made by sol-gel showed uniform particle size and good properties. It has been reported that La-doped SrTiO3 as an anode material of solid oxide has good electrical conductivity properties and chemical stability. Moreover, this material has been found to be dimensionally stable during oxidation–reduction cycling. However, doped SrTiO3 shows poor electro-catalytic activity towards hydrogen and methane, so in the La-doped SrTiO3 add CeO2, so that after the composite material has the advantages of two materials.In this study, the effect of A-site deficiency level on the performance of (La0.4Sr0.6)1-xTiO3-δhas been studied and also been investigated the performance of (La0.4Sr0.6)1-xTiO3-δcomposite anode material with the temperature. Microstructure and performance of CeO2 or SDC and Ni to La0.4Sr0.6TiO3-δhas been studied, CeO2 or SDC and Ni adjusted the microstructure of La0.4Sr0.6TiO3-δand modified electrochemical performance of composite anode material.(1) La doped strontium titanate with A-site deficiency ((La0.4Sr0.6)1-xTiO3-δ)was synthesized by sol-gelmethod. The deficiency limit of A-site in (La0.4Sr0.6)1-xTiO3-δis below 9mol% ,in the air at,1500℃sintered samples. The electrical conductivity of (La0.4Sr0.6)1-xTiO3-δsamples increases with increasing A-site deficient amount. The defect chemistry analysis indicates that the introduction of A-site deficiency results in not only the increase of oxygen vacancy concentration but also allows the increases of strontium vacancies concentration.(2) La-subtituted SrTiO3 materials show high electrical conductivity in reducing atmosphere, a good dimensional and chemical stability upon redox cycling, but the electrocatalytic activity for H2 oxidation is very poor.However, it is possible to improve its activity introducing the addition of CeO2 to La doped SrTiO3 can combine the advantages of these two materials. La-doped SrTiO3-δ(LST)–xCeO2 (x = 0,30, 40, 50) composites were evaluated as anode materials for solid oxide fuel cells in terms of chemical compatibility, electrical conductivity and fuel cell performance in H2. Although the conductivity of LST–xCeO2 composite slightly decreased from 3.329 to 1.474 S cm-1 inH2 at 800℃as the content of CeO2 increased, the fuel cell performance improved from22.1 to 71.37mWcm2 in H2 at 800℃. X-ray diffraction showed that LST had good chemical compatibility with CeO2. Thermal expansion test showed that its thermal expansion behavior was close to that of SDC. All test result demonstrated the potential ability of LST–xCeO2 to be used as SOFC anode.(3) A new ceramic-based multi-component material, containing one electronic conductor La-doped SrTiO3 (LST), one ionic conductor Ce0.85Sm0.15O1.925 (SDC) and a small amount (4 wt.%) of Ni catalyst, was investigated as an alternative anode material for solid oxide fuel cells (SOFC). The ceramic framework LST-SDC-Ni shows good dimensional stability under typical anode conditions and has an electrical conductivity of～2 S cm-1 in H2. Owing to the substantial electrocatalytic activity of the fine and well-dispersed Ni particles in the ceramic framework, the fuel cell LSTN1 and LSTN2 maximum power density obtained at 800℃was 40.16 and 117.41 mWcm2 in H2 atmosphere. Based on these results, the potential ability of LST–xCeO2 to be used as SOFC anode.
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