For A-site substituted AA'BO₃ perovskite, the doped A' element is easy to migrate to the surface and form segregation of A'O_x, which could partially block active B sites and thus reduce catalytic activity. In the present work a La_0.8Sr_0.2CoO_3-δ perovskite-type solid was first prepared and then treated with acetic acid to eliminate SrO segregation on its surface. The obtained catalyst (LCSO-a) possessed a significantly enhanced catalytic activity for toluene oxidation in the 220–260 °C range. This promotion effect might be attributed to the increase in the concentration of active surface oxygen species and the reduction in their binding strength. In addition, the LCSO-a catalyst showed very good stability and water resistance.

对于A位取代的A'BO ₃钙钛矿，掺杂的A'元素易于迁移至表面并形成A'O _x偏析，这可能会部分阻断活性B位，从而降低催化活性。在目前的工作中，La _0.8 Sr _0.2 CoO3 _-δ首先制备钙钛矿型固体，然后用乙酸处理以消除表面上的SrO偏析。所获得的催化剂（LCSO-a）在220–260°C的范围内具有显着增强的甲苯氧化催化活性。这种促进作用可能归因于活性表面氧种类的浓度增加和它们的结合强度降低。另外，LCSO-a催化剂显示出非常好的稳定性和耐水性。