“…The SACs possess distinct active sites or catalytic pathways different from those of conventional metal catalysts, exhibiting superior activity and selectivity towards oxygen reduction 6 – 8 , CO oxidation 1 , 9 , hydrogenation reactions 5 , 10 , and other important reactions 11 – 16 . During the past decade, various concepts for atomic dispersion of metals on solid supports have emerged, such as the utilization of vacancy defects on supports 17 – 19 , fabrication of metal-organic frameworks (MOFs) 20 , 21 , spatial confinement in zeolites 22 , 23 , and enhancement of the metal-support interactions 3 , 24 – 26 . However, these routes involve fussy synthetic steps and sensitive conditions, including adsorption and reduction of metal precursors 27 , 28 .…”