Plasma‐treated Ni‐Al‐O Catalysts with Variable Physicochemical Properties for the Oxidative Dehydrogenation of Ethane

Abstract Ni‐M‐O catalysts have demonstrated superior performance in the oxidative dehydrogenation of ethane (ODHE), but precise control over the content of active oxygen species is necessary to achieve optimal C 2 H 4 selectivity. In this work, highly efficient Ni‐Al‐O catalysts were prepared by a plasma‐assisted strategy, and their catalytic properties were evaluated for ODHE reaction. Characterization results revealed that the working atmospheres (O 2 , H 2 and Ar) can not only change the crystallite size of NiO, but also modulate the reduction properties of Ni‐Al‐O catalysts and the distribution of active oxygen species. Consequently, Ar and O 2 plasma pretreatment increased the ODHE performance by increasing active surface oxygen, while H 2 plasma‐treated catalyst showed a decrease in the catalytic performance compared to the original Ni‐Al‐O catalyst. Among them, O 2 ‐Ni‐Al‐O exhibited 50.8 % ethane conversion and 70.3 % ethylene selectivity at 500 °C. It was accepted that the change in the ratio of defective oxygen to lattice oxygen (O V /O L ) was the internal reason to illustrate its excellent performance. For series Ni‐Al‐O catalysts, C 2 H 6 conversion increased linearly while C 2 H 4 selectivity decreased with an increase in O V /O L value.