Abstract: The perovskite-like LaSrCoO₄ mixed oxides with K₂NiF₄ structure were prepared by the gelatin,
polyglycol gel and polyacrylamide gel methods and used successfully for CO and C₃H₈ oxidation. These samples were investigated by using the
XRD, TEM, BET, TPR and TPD methods. The effects of preparation methods on structure and performance of LaSrCoO₄ were studied. The results indicate
that all La_2-xSr_xCoO₄ have tetragonal K₂NiF₄ structure, their structure and catalytic activities change with the change of the
preparation methods. T* phase appears in LaSrCoO₄ prepared by the polyacrylamide gel method, and the lower the calcination temperature is,
the more the T* phase appears. At the order of LaSrCoO₄ prepared by gelatin method, polyglycol gel method and polyacrylamide gel method,
their BET surface areas, oxygen vacancies, mobile lattice oxygen and catalytic activities gradually increase, in addition, the lower calcination temperature is advantageous to these changes.

Key words: LaSrCoO₄, perovskite-like, preparation method, oxidation