“…Owing to the virtues of ultimate atomic utilization, tunable coordination environment, and exceptional catalytic properties, single-atomic site catalysts (SACs) have been emerging as a rising star for highly efficiently photocatalyzing CO 2 RR. , Nevertheless, the structural uniformity of the active sites in SACs offers an atomic-scale perspective to reveal the relationship between the structure and catalytic activity. , Actually, quite a number of SACs including Ni-SA-x/ZrO 2 , Er 1 /CN-NT, W 18 O 49 @Co, Cu SAs/UiO-66-NH 2 , and Co-SA@SP-800 have been developed to catalyze the CO 2 photoreduction. In particular, catalysts with bimetallic active sites were revealed to be able to improve the catalytic performance of various reactions. − However, the application of atomic-pair catalysts (APCs) over CO 2 photoreduction appears to still remain unreported, to the best of our knowledge.…”