Valence state of transition metal center as an activity descriptor for CO2 reduction on single atom catalysts

We found three excellent CO2 conversion single-atom catalysts and a simple but effective descriptor to describe the trend in catalytic activity by first principle calculations. [Display omitted] •The catalytic activities of TM atoms decorated Ti2CO2 towards CRR are investigated.•Three single atom catalysts are selected as promising electrocatalysts for CRR.•The valence state of TM atoms can be used as a descriptor to evaluate the catalytic activity.