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Complex oxides A2BO4 with perovskite-like K2NiF4-type structure are of specialinterest due to their particular crystal structure, outstanding electromagnetic property,preferable stability at high temperature,planar conductor, transport properties betweensemiconductor and metal as well as their ability to catalyze a large number ofoxidation and reduction reactions.Hence, they have become new-style materialswhich have better foreground than ABO3 mixed oxides. Catalytic activity of theA2BO4 mixed meterials directly relate to the cation composition of A-site and B-site,quantivalence of transition metal B-site and crystal structure. At present, somereferences have reported the Cu-based and Ni-based mixed oxides, a few references inrelation to Co-based mixed oxides has been found, so it’s very necessary for us tostudy the Co-based mixed oxides.In the dissertation, the LaSrCoO4 and La1-xAxSrCoO4 mixed oxides were preparedusing polyacrylamide macromolecule gel method. The catalytic oxidation of CO andCalls used as probe reaction, the experiments were carded out in such a way that allfactors affecting the catalytic activities [the different element doped: rare earths（Nd,Ce） and transition metals （Ni,Fe,Mn）, different preparation methods and differentcontent doped of Nd and Ni]. Most of the catalysts were characterized by means ofXRD, IR, BET, H2-TPR, O2-TPD, respectively.LaSrCoO4 catalysts of A-site doped different rare earths （Nd,Ce） and transitionmetals Ni,Fe,Mn) were synthesized by polyacrylamide macromolecule gel method.According to XRD and IR data, most of the catalysts had formed the perovskite-likestructure. With Nd-doping, LaSrCoO4 catalyst have more content of Co3+, quantity ofsurface adsorbed oxygen and lattice oxygen, so enhance catalytic actiities for CO andC3H8 oxidation. Unlike, Ce doped reduces the catalytic activities of LaSrCoO4catalyst.The different preparation methods and Ni （or Nd） doped content seems to bean important factor in structure and catalytic activities of the catalysts..In the paper,polyaerylamide macromolecule gel method, polyglyeol gel method and evaporation-decomposition method were used, and found that the catalyst perpared usingpolyacrylamide macromolecule gel method was shown to be the best active. Becausethe catalyst prepared with this method has bigger surface area, samaller crystal size,more surface adsorbed oxygen and lattice oxygen, and lower activation energybesides, all these seems to be crucial factor in the catalytic activities for oxidation of CO and C3H8. In the catalytic process,where the the content of Nd-doped seems to bevery important, suitable content of Nd-doped increase the catalytic activities of theLaSrCoO4catalyst, since this catalyst reduces crystal size, increases lattice distortionsand lattice oxygen. Fe Doping into LaSrCoO4 catalyst dosen’t change the catalyticactivities greatly. Ni-doped can enhance the catalytic activies, by the reason that it canreduce crystal size, increase the lattice distortions, the content of oxygen vacancy andlattice oxygen, and reduce the activation energy. Ni.（x=0.1-0.7） doped content affectsthe properties of LaSrCoO4 catalyst. Suitable Ni （x=0.3）doping into LaSrCoO4catalyst is favorable for the catalytic activity. This can be interpreted that theLa0.7Ni0.3SrCoO4 catalyst has smaller crystal size and bigger lattice distortions.
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