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考察碱土金属氟化物／三氧化二钆在甲烷氧化偶联反应中的催化性能．发现在Ｇｄ＿２Ｏ＿３中添加碱土金属氟化物，Ｃ＿２选择性和收率都有明显提高。当Ｇｄ＿２Ｏ＿３摩尔含量相同时，催化性能按Ｃａ－Ｓｒ－Ｂａ顺序递增，在８０％ＢａＦ＿２／Ｇｄ＿２Ｏ＿３催化剂上Ｃ＿２选择性和收率分别达５９．５％和１８．７％．ＸＲＤ分析结果表明，在含氟催化剂中出现了四方Ｇｄ＿４Ｏ＿３Ｆ＿６新相，其结构与立方ＣａＦ＿２，ＳｒＦ＿２和ＢａＦ＿２相似．可能有利于物相之间的匹配及载流子传递．ＸＰＳ测试发现，催化剂表面上存在着（或Ｏ￣－）物种．与Ｇｄ＿２Ｏ＿３相比，在含氟的催化剂中，Ｏ＿１ｓ结合能较高，表明该吸附氧物种所带电荷较少，对提高Ｃ＿２选择性有利。
The catalytic performance of alkaline earth metal fluoride / gadolinium oxide in methane oxidative coupling reaction was investigated. It was found that the addition of alkaline earth metal fluoride to Gd 2 O 3 significantly improved the selectivity and yield of C 2. When the molar amount of Gd 2 O 3 is the same, the catalytic performance increases in the order of Ca-Sr-Ba. The selectivity and yield of C 2 on the 80% BaF 2 / Gd 2 O 3 catalyst are 59.5% and 18.7%, respectively. The results of XRD analysis show that the tetragonal Gd_4O_3F_6 new phase appears in the fluorine-containing catalyst, and its structure is similar to the cubic CaF_2, SrF_2 and BaF_2. May be conducive to the match between the phase and carrier transfer. The XPS test found that there are (or O ~ -) species on the surface of the catalyst. Compared with Gd_2O_3, the binding energy of O_1s is higher in the fluorine-containing catalyst, indicating that the oxygen species of the adsorbed oxygen species has less charge and is favorable for increasing the C_2 selectivity.