Stronger Together! Mechanistic Investigation into Synergistic Effects during Homogeneous Carbon Dioxide Hydrogenation Using a Heterobimetallic Catalyst.

A series of group 6 heterobimetallic complexes [M;Ir] (M = Cr, Mo, W) were synthesized and fully characterized, and the catalytic behavior was studied. The heterobimetallic complex [Mo;Ir] () was by far the most active and has shown a considerable synergistic effect, with both metals actively participating in homogeneous carbon dioxide hydrogenation, leading to formate salts. Based on theoretical calculations, the synergistic interaction is due to Pauli repulsion, lowering the transition state and thus enabling higher catalytic activity.

Synergistic Catalysis in Heterobimetallic Complexes for Homogeneous Carbon Dioxide Hydrogenation.

Two heterobimetallic Mo,M' complexes (M' = Ir, Rh) were synthesized and fully characterized. Their catalytic activity in homogeneous carbon dioxide hydrogenation to formate was studied. A pronounced synergistic effect between the two metals was found, most notably between Mo and Ir, leading to a fourfold increase in activity compared with a binary mixture of the two monometallic counterparts.