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采用ＸＲＤ， ＬＲＳ，ＦＴＩＲ， ＵＶＤＲＳ和ＴＰＲ 研究了ＭｏＯ３ 在载体Ｇａ２Ｏ３ 上的分散情况．结果表明： ＭｏＯ３ 的分散状态受Ｇａ２Ｏ３ 表面结构的影响， ＭｏＯ３ 在Ｇａ２Ｏ３ 上的分散容量约为８－４μｍｏｌ／ｍ２ ； 低于该分散容量时， Ｍｏ６ ＋ 主要以高分散态存在于Ｇａ２ Ｏ３ 表面，而高于该分散容量时，除有分散态的Ｍｏ—Ｏ 物种外，还有残余的ＭｏＯ３ 晶相出现．ＴＰＲ 结果表明： ＭｏＯ３ 低于分散容量时，体系中只观察到两个有关钼物种的还原峰（４００ ℃和８５０ ℃） ； 高于分散容量时， 又出现一个新还原峰（５５０ ℃） ．４００ ℃处的峰为分散态钼物种中的Ｍｏ６ ＋ 还原为Ｍｏ４ ＋ ；５５０ ℃处的峰为ＭｏＯ３ 晶相中的Ｍｏ６ ＋ 还原为Ｍｏ４ ＋ ；８５０ ℃处的峰为Ｍｏ４ ＋ 还原为Ｍｏ０ ． 结合嵌入模型对这些实验事实进行了解释．
The dispersion of MoO3 on Ga2O3 was studied by XRD, LRS, FT-IR, UV-DRS and TPR. The results show that the dispersion state of MoO3 is affected by the surface structure of Ga2O3, and the dispersion capacity of MoO3 on Ga2O3 is about 8-4μmol / m2. Below the dispersion capacity, Mo6 + exists mainly on the surface of Ga2O3 in a highly dispersed state. Above this dispersion capacity, in addition to the dispersed Mo-O species, a residual MoO3 crystal phase appears. TPR results show that when MoO3 is below the dispersion capacity, only two reduction peaks (400 ℃ and 850 ℃) of molybdenum species are observed in the system, and a new reduction peak (550 ℃) appears above the dispersion capacity. The peak at 400 ℃ is the Mo6 + reduction of Mo4 + in the dispersed molybdenum species to Mo4 +; the peak at 550 ℃ is the Mo6 + reduction in the MoO3 crystal phase to Mo4 +; the peak at 850 ℃ is the Mo4 + reduction to Mo0. These experimental facts are explained with the embedded model.