Boosting Light‐Driven CO2 Conversion Into CO by a Polypyridine Iron(II) Catalyst Using an Organic Sensitizer

Direct photochemical conversion of CO2 into a single carbon-based product currently represents one of the major issues inthe catalysis of the CO2 reduction reaction (CO2RR). In this work,we demonstrate that the combination of an organic photo-sensitizer with a heptacoordinated iron(II) complex allows toattain a noble-metal-free photochemical system capable ofefficient and selective conversion of CO2 into CO upon lightirradiation in the presence of N,N-diisopropylethylamine (DIPEA)and 2,2,2-trifluoroethanol (TFE) as the electron and protondonor, respectively, with unprecedented performances (ΦCO upto 36 %, TONCO > 1000, selectivity > 99 %). As shown bytransient absorption spectroscopy studies, this can be achievedthanks to the fast rates associated with the electron transferfrom the photogenerated reduced dye to the catalyst, whichprotect the dye from parallel degradation pathways ensuring itsstability along the photochemical reaction. These results pointout how the profitable merging of molecular species based oncheap and abundant elements can have great potential totarget efficient and selective transformations crucial for theconversion of solar energy into fuels