Co-exsolution and Deflagration as Synthesis Methods for Creating Stable Methane Oxidation Catalysts

The exploitation and control of structure in methane reforming catalysts remains a significant challenge to chemists and engineers worldwide. Currently, methane conversion catalysts are limited by their ability to resist surface carbon accumulation, sintering, and unwanted oxidation. These mechanisms are detrimental to catalyst lifetime and have prevented processes such as methane dry reforming from large scale industrialization. All of these deactivation mechanisms are highly influenced by the strength of the interaction between the active catalyst and its support, as well as the size and shape of the active catalyst phase. We explore here two methods for growing highly stable catalysts to withstand harsh reforming conditions:

1) solid phase crystallization and

When exposed to hydrogen at high temperatures, ordered ceramics can exsolve metallic nanoparticles by breaking the M-O bonds. We explore the effect of shape, size, and the presence of 2D and 3D defects in the LaNiO₃ structure on its ability to exsolve stable Ni-alloy nanoparticles for catalysis.

2) deflagration of high-nitrogen energetic ligands.

Nitrogen-rich compounds are a popular class of energetic material due to the large amount of energy released upon combustion and their low pollution rate, releasing mostly N₂. These materials are commonly used as propellants, explosives, or as gas generators. Here, we report the first synthesis of a "supported catalyst" synthesized by the co-combustion of high-nitrogen energetic materials complexed with metal atoms.