Non-Functionalized Subnanometer Copper Nanoparticles for Low-Temperature Methane Activation

High Resolution Image Download MS PowerPoint Slide Subnanostructured particles (SNPs) have recently attracted attention as potential materials to activate inert molecules such as methane. Copper-based SNPs particularly have been focused on activating methane at low temperatures. However, conventional SNPs have often been prepared starting from multinuclear metal complexes stabilized by organic ligands or single-site heterogeneous catalysts in porous materials to avoid aggregation of the SNPs, and the reasons for enhancement of reactivities with a decrease in the particle size have been uncleared by a variety of factors involving the ligand effect. The reactivities of SNPs without organic ligands or cages have not been revealed to date. Herein, we present the precise preparation and unique atomic configuration of naked subnano copper minerals, which were not covered with any protecting ligands. Methane activation was achieved with naked copper SNPs under mild conditions. These results highlight the structural reasons in the copper SNPs for reactivities that provide significant enhancement of the reactivity of methane molecules with molecular oxygen.