Fig. 4: Theoretical calculated energy diagram of the Co-SxN4−x SACs.

a Bader charge analyses. b Calculated potential free energy diagrams for CO2RR to CO on the Co-SxN4−x SACs. c Evolution of free energy of the COOH* formation and CO* desorption steps associated with the S numbers in the Co-SxN4−x SACs. d Trend of the calculated limiting potentials and measured jCO/ECSA correlated with the number of S in the Co-SxN4−x SACs.