In contrast to many heterogeneous c

In contrast to many heterogeneous catalysts, molecular catalystsoffer the advantage of synthetic control over the steric and electronicproperties in the vicinity of the active site. This in turn enablesmechanistic studies to address structure–function relationshipsthat then induce rational design of new catalyst structures towardsimproved performance. Homogeneous catalysts have been used inthe context of CO 2 RR for decades . These systems have shown highselectivity, with near unity product Faradaic efficiency (FE), for COor HCOO – (HCOOH), and progress towards more reduced prod-ucts such as CH 4 is emerging 5