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以纯ＮｉＯ为模型催化剂考察了乙烷氧化脱氢（ＯＤＨＥ）性能，发现非化学计量氧的存在与反应的活性及选择性密切相关．ＴＧＡ研究结果表明，５００℃制备的样品具有ｘ≈６％的非化学计量氧．Ｈ２ＴＰＲ结果表明，非化学计量氧与晶格氧的可还原性明显不同；Ｏ２ＴＰＤＭＳ又把非化学计量氧区分为两个氧物种，Ｏ－２和Ｏ－（或Ｏ２－２）．脉冲试验结果表明，非化学计量氧对ＯＤＨＥ制乙烯是选择性反应的活性氧物种，晶格氧是完全氧化反应的活性氧物种．一旦催化剂中非化学计量氧耗尽并动用晶格氧时，催化剂便有Ｎｉ０生成，表现出自催化性能，使反应活性迅速提高，但产物均为ＣＯ２，ＣＯ，ＣＨ４等完全燃烧或裂解产物．为保持有较高的乙烯收率，反应处于稳态时Ｎｉ必须处于高价态．电导测定结果表明，优良的ＯＤＨＥ催化剂应有Ｐ型半导性．
Pure NiO was used as catalyst to investigate the performance of ODHE. It was found that the existence of non-stoichiometric oxygen was closely related to the activity and selectivity of the reaction. TGA results show that samples prepared at 500 ° C have x ≈ 6% non-stoichiometric oxygen. H2-TPR results show that the non-stoichiometric oxygen and lattice oxygen was significantly different reducibility; O2 TPD MS again non-stoichiometric oxygen is divided into two oxygen species, O-2 and O- (or O2-2 ). The results of the pulse test showed that non-stoichiometric oxygen is a selective reactive species of oxygen to ODHE ethylene, and lattice oxygen is a fully oxidized reactive oxygen species. Once the non-stoichiometric oxygen in the catalyst is exhausted and the lattice oxygen is used, the catalyst will be Ni0 generated, showing the autocatalytic properties, so that the reaction activity increased rapidly, but the products are completely combustion or cracking products such as CO2, CO, CH4. To maintain a high ethylene yield, Ni must be at a high valence state when the reaction is in steady state. Conductivity measurements show that good ODHE catalyst should be P-type semiconducting.