Denary oxide nanoparticles as highly stable catalysts for methane combustion

Oxide nanoparticles with elemental and structural diversity are widely studied for catalysis and energy applications. While compositional control holds great promise for materials discovery, current oxide nanoparticles are typically limited to a few cations due to the intrinsic complexity in nanoscale multi-element mixing. Here we report the rational design and synthesis of single-phase multi-element oxide nanoparticles with tunable composition, size and structure. We have identified temperature-, oxidation- and entropy-driven synthesis strategies to mix a range of elements with largely dissimilar oxidation potentials (including palladium), thus greatly expanding the compositional space. Through rapid synthesis and screening, we obtained a denary multi-element oxide catalyst showing high performance and superior stability for catalytic methane combustion over 100 hours due to the high-entropy design and stabilization. Our work therefore provides a viable synthesis route with clear guidelines for multi-element oxide nanoparticles and enables materials design in the multi-element space towards highly stable catalysts. Multi-element oxide catalysts can feature superior properties compared with their single-element analogues but obtaining such complex structures remains a challenge. Here, a method is reported to access single-phase denary nanoparticles as stable and efficient catalysts for the combustion of methane.