The role of adsorbed oxygen for the ethane oxidative dehydrogenation on NiO(110) and (100) surface: A DFT theoretical study

Abstract

NiO based catalysts possess superior low-temperature (below 450 °C) reactivity and fine C2H4 yield (46% at 400 °C) for oxidative oxidation of ethane. The DFT + U method is employed to explore reaction pathways of C2H6 over NiO(100) and NiO(110) surface. The reaction follows the Mars-van Krevelen mechanism. The significant difference of the hydrogen adsorption capacity derived from lattice oxygen leads to the changed the rate determining step. NiO(100) surface tends to form C2H4 because of a relative easier desorption process. This work provides a comprehensive understanding from the theoretical level for NiO-based catalysts during C2H6-ODH process.

Keywords

• Oxidative dehydrogenation
• Adsorbed O2
• Oxygen vacancy
• Determining step