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以ＭｏＯ_３为前身化合物，在Ｈ_２／Ｎ_２混合气氛中利用程序升温反应方法制备了钝化后比表面为 １１５ ｍ~２· ｇ~（－１）的γ－Ｍｏ_２Ｎ粉末催化剂．在低温条件下，该催化剂显示出良好的 ＣＯ氧化反应活性．借助Ｘ射线电子能谱（ＸＰＳ）、电子自旋共振（ＥＰＲ）及激光Ｒａｍａｎ光谱（ＬＲＳ）技术对氮化铝的表面钝化层进行了表征，结果表明其中钼以混合价态存在并得到了Ｍｏ~（５＋）（ｇ＝１．９３２，ｇ／／＝１．８９２）存在的证据，同时还发现了超氧负离子Ｏ~－（２_）（ｇ＝２．００１，Ｒａｍａｎ吸收峰１１２４ Ｃｍ~（－１））的存在．研究表明，它的产生与 ＭＯ~（５＋）／ＭＯ~（４＋）氧化还原电对的转换存在着协同性， Ｏ~－（_２）可能是 ＣＯ氧化反应的活性氧种．
Γ-Mo_2N powder catalyst with a specific surface area of 115 m 2 · g -1 was prepared by a programmed temperature-programmed reaction in a H 2 / N 2 mixed atmosphere with MoO 3 as the precursor. The catalyst shows good CO oxidation reactivity at low temperature. The surface passivation layer of aluminum nitride was characterized by X-ray photoelectron spectroscopy (XPS), electron spin resonance (EPR) and laser Raman spectroscopy (LRS). The results show that molybdenum exists in a mixed valence state (5) (g = 1.932, g // = 1.892). At the same time, it was also found that the superoxide anion O ~ - (2 _) (-1)). The results show that there is synergy between its production and conversion of MO ~ (5 +) / MO ~ (4+) redox couple. O ~ - (_2) may be the active oxygen species of CO oxidation reaction.