Partial oxidation of methane (POM) is considered a promising industrial method for producing syngas, a mixture commonly used to make fuels and chemicals. For years, scientists have assumed that metallic nickel (Ni) nanoparticles serve as the main active centers that drive this reaction. However, there has been an important unresolved question. The metallic Ni observed after a reaction may simply form when nickel oxide is reduced by syngas at high temperatures, rather than representing the species that actually performs the catalysis.
Nickel can change both its oxidation state and its atomic arrangement under the high-temperature redox conditions involved in POM. Until now, these changes have been difficult to track in detail, making it challenging to determine the true structure responsible for the reaction.
A Hidden Active Structure Forms During the Reaction
In a recent study published in Nature Catalysis, researchers found that highly active structures can form in situ when the surface of NiO reconstructs during POM. The results reveal the atomic-scale source of the catalytic activity and show why it is important to observe catalysts while they are operating under realistic reaction conditions.
