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应用原位傅里哀变换红外光谱方法，分别在４００～４５０℃、常压、高空速（１２０００～１４４００ｈ．ｓ．ｖ．ｇ．）的Ｈ２、Ｎ２／３Ｈ２或Ｎ２气氛的动态条件下，检测了双促进氨合成铁催化剂上的化学吸附物种，并分别在Ｄ２、Ｎ２／３Ｄ２或１５ＮＨ３／Ｈ２气氛中，进行了常规同位素验证实验．结果表明，催化剂表面的主要含氮化学吸附物种是分子态的Ｎ２．ａｄ，其ｕ（Ｎ－Ｎ）＝２０３６ｃｍ－１（ｓ），２０１２ｃｍ－１（ｗ）和１９３５ｃｍ－１（ｗ），而不是原子态的Ｎａｄ，其ｕ（Ｆｅ－Ｎ）＝１０８７ｃｍ－１（ｖｗ），和ＮＨａｄ其ｕ（Ｆｅ－Ｎ）＝８８６ｃｍ－１（ｖｗ），表面有相当量的化学吸附氢存在，其ｖ（Ｆｅ－Ｈ）＝２０５６ｃｍ－１（ｓ），１９５０ｃｍ－１（ｍｓ），１９３１ｃｍ－１（ｍ），１９０２ｃｍ－１（ｗ），９１５ｃｍ－１（ｓ，桥式）等．作为与报道过的激光拉曼光谱的互补研究，本结果支持了以缔合式途径为主、解离式途径为次的平行竞争缔合式合成氨催化反应机理．
In situ Fourier transform infrared spectroscopy was used to detect the dynamic changes in the atmosphere of H2, N2 / 3H2 or N2 at atmospheric pressure and high airspeed (12000-14400 h.s.v.g.) At 400-450 ℃ respectively. The double-promoted chemosorbent species on the ammonia synthesis iron catalyst were carried out routine isotope verification experiments in D2, N2 / 3D2 or 15NH3 / H2 atmosphere respectively. The results show that the main nitrogen-containing chemisorption species on the catalyst surface are molecular N2. ad with u (Fe-N) = 1087 cm -1 (u-N) = 2036 cm -1 (s), 2012 cm -1 (w) and 1935 cm -1 (w) (v-Fe) = 2056cm-1 (s), 1950cm-1 (ms) and von Fe-N = 886cm- ), 1931 cm-1 (m), 1902 cm-1 (w), 915 cm-1 (s, bridge) and the like. As a complementarity study with reported laser Raman spectra, the results support the parallel competitive associative catalytic reaction mechanism of ammonia synthesis, which is dominated by the association pathway and the second is the dissociation pathway.