Ag2(0) dimers within a thioether-functionalized MOF catalyze the CO2 to CH4 hydrogenation reaction

Ultrasmall silver clusters in reduced state are difficult to synthesize since silver atoms tend to rapidly aggregate into bigger entities. Here, we show that dimers of reduced silver (Ag-2) are formed within the framework of a metal-organic framework provided with thioether arms in their walls (methioMOF), after reduction with NaBH4 of the corresponding Ag+-methioMOF precursor. The resulting Ag-2-methioMOF catalyzes the methanation reaction of carbon dioxide (CO2 to CH4 hydrogenation reaction) under mild reaction conditions (1 atm CO2, 4 atm H-2, 140 degrees C), with production rates much higher than Ag on alumina and even comparable to the state-of-the-art Ru on alumina catalyst (Ru-Al2O3) under these reaction conditions, according to literature results.

Automated summary

Dimers of reduced silver (Ag-2) were successfully synthesized within a metal-organic framework. The resulting catalyst, Ag-2-methioMOF, showed high catalytic activity in the methanation reaction of carbon dioxide under mild reaction conditions.