Research Of Anode Reaction Performance Of SOFC Feeded With CH₄-H₂ And Anode Material

Solid oxide fuel cell (SOFC) is an all solid-state energy conversion device operated at high temperatures with the advantage of high efficiency, little pollution and no expensive metal catalyzer. SOFC attracts more and more attention all over the world for lack of power resources and environmental pollution. However, at present, there are so many basic problems about SOFC were not solved.This thesis mainly researched the anode reaction of Ni/YSZ anode feeded with CH₄ and the restrain effect of H₂ to carbon deposition which feeded with CH₄-H₂ through the studies about the actuality of the SOFC, and the Cu-Ce-Zr-O anode material was prepared which long-term stability was reaserched.The main work and conclusions of this paper are as follows:(1) The output performance of SOFC was increased along with the increasing of stress and temperature when feeded with CH₄-H₂ .The main reaction of anode was CH₄ partial oxidation at open circuit and operation temperature of 800℃～1000℃; added H₂ can restrained the extent cracking of CH₄, and the carbon deposition was decreased along with the increasing of the amount of H2.(2) The electronic performance of SOFC has the best value when the ratio of CH₄:H₂ reached a fixed value at different CH₄ concentration; the best ratio value of CH₄:H₂ were 1:4, 1:2 and 1:1.5 which CH₄ concentration were 12.7%, 16.4% and 20.0%, respectively; the performance of cell will be decreased when the best ratio value was increased or decreased; retaining the best ratio value of CH₄:H₂, the electronic performance of SOFC also has the best value when N₂ concentration were 28.6%, 42.5% and 50%, respectively.(3) Co-precipitation and citric acid sol-gel were used to prepare the 10%CuO-Ce_0.15Zr_0.85O₂ catalyzer, respectively. The single cells were also prepared with Cu-Ce-Zr-O anode material. From XRD pattern we can see that two catalyzer prepared with different technics were well crystallized at 600℃and 800℃, respectively. The characteristic apex of cubic and orthorhombic phase of ZrO₂ can be found in XRD pattern, and the cubic phase is the main phase. Through SEM analysis we found that these two method all can prepare fine anode, compared with the method of Co-precipitation the particles size of catalyzer prepared with technology of citric acid sol-gel is smaller and the porosity is more enough, which anode structure is the better one of them. For prevent the crack of electrolyte substrate, compound cathode was prepared with technology of slurry coating and co-sintering. Compared with conventional single cell with Ni/YSZ anode, the output performance of the cell prepared with technology of co-precipitation is lower. Think from the aspect of stabilization of the cells, the cells prepared with these two technologies have good stabilization and durability.