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受主杂质Ｍ（Ｌｉ＋、Ｍｇ２＋、Ａｌ３＋）部分替代ＣａＴｉＯ３中Ｔｉ４＋形成的ＣａＴｉ０．９Ｍ０．１Ｏ３－δ具有稳定的类似ＣａＴｉＯ３的正交晶格结构．掺杂元素的价态变化与样品的ｐ型导电性、活泼氧物种的形成及甲烷氧化偶联（ＯＣＭ）的活性之间有着规律性的依赖关系，即随掺杂元素价态降低，Ｐ型导电性增强，活泼氧物种的浓度增加，Ｃ２选择性和收率也相应提高．其中ＣａＴｉ０．９Ｌｉ０．１Ｏ３－δ的Ｐ型电导最大，它的ＯＣＭ性能也最好，其甲烷转化率为３５．７％，Ｃ２选择性５３．９％，Ｃ２收率１９．２％．ＴＰＲ和ＸＰＳ结果证明掺杂可引起活泼氧物种的形成，活泼氧物种的浓度和它的迁移能力与掺杂元素的价态有关．纯ＣＨ４与催化剂表面晶格氧物种的反应表明，催化剂表面上通常的晶格氧物种Ｏ２－有利于甲烷的完全氧化生成ＣＯｘ，而掺杂引起的活泼氧物种Ｏδ－（０＜δ＜２）有利于甲烷的偶联生成Ｃ２烃．ＣａＴｉ０．９Ｌｉ０．１Ｏ３－δ在１５０ｈ内ＯＣＭ的反应性能稳定，说明杂质Ｌｉ占据晶格中Ｔｉ位置后，可使Ｌｉ的流失速率大大减慢．
The CaTi0.9M0.1O3-δ formed by partial substitution of acceptor M (Li +, Mg2 +, Al3 +) for Ti4 + in CaTiO3 has a stable CaTiO3-like orthorhombic lattice structure. Variations of the valences of the doping elements have a regular dependence on the p-type conductivity of the sample, the formation of the active oxygen species and the activity of the methane oxidative coupling (OCM). That is to say, as the valence of the doping element decreases, the p- Conductivity increases, the concentration of active oxygen species increases, C2 selectivity and yield also increased accordingly. Among them, the conductivity of P type of CaTi0.9Li0.1O3-δ is the largest, and its OCM performance is also the best. The conversion of methane is 35.7%, the selectivity of C2 is 53.9% and the yield of C2 is 19.2%. TPR and XPS results show that doping can lead to the formation of active oxygen species. The concentration of active species and their migration ability are related to valence of doping elements. The reaction of pure CH4 with the lattice oxygen species on the surface of the catalyst showed that O2-, which is usually the lattice oxygen species on the surface of the catalyst, favors the complete oxidation of methane to COx, while the active oxygen species Oδ- (0 <δ <2) Conducive to the coupling of methane to generate C2 hydrocarbons. The reaction performance of CaTi0.9Li0.1O3-δ was stable within 150h, indicating that the loss rate of Li could be greatly slowed down when the impurity Li occupied the Ti site in the lattice.