Magnetic core-shell composites accessed by coordination assembly boost catalytic CO2 valorization

Abstract

Magnetic core-shell composites are readily accessed by encapsulating Fe3O4 nanoparticles with NHC-M (M = Ir, Pd) coordination assemblies, which function as solid molecular catalysts and exhibit enhanced catalytic activity compared to the corresponding bis-NHC-Ir molecules in both hydrogenation and dehydrogenation reactions related to CO2. A record turnover number (TON: 1.69 × 106) was achieved in the hydrogenation of CO2 to formic acid. In addition, robust solid catalysts can be magnetically recovered and reused for more than 11 runs without obvious loss in activity and selectivity for the dehydrogenation of ammonium formate, even at 10–6 mmol level catalyst loadings.