Brief introduction of some information on Fe-SACs.

Sample	Active site	Precursor	Loading rate	Application	Reference
S,N–Fe/N/C–CNT	Fe–Nx	FeCl3, KSCN, carbon nanotubes, 2,2′-bipyridine		ORR, OER	16
Fe–NC SAC	Fe–N4	Fe (NO3)3, glucose, oxygen-rich porous carbon, melamine	12.1wt%	CO2RR	17
Fe–Nx–C	Fe–Nx	FeSO4, Phen, ZIF-8	0.81wt%	ORR	18
CNT/PC	Fe–N4	Fe(iii)TMPPCl, PC, carbon nanotubes	2.9wt%	ORR	30
Fe/N–GPC	Fe–N4	FeCl3, dicyandiamide, MIL-101-NH2	1.1wt%	ORR	31
Fe SAS/N–C	Fe–N4	PEI, Phen, FeCl2, C3N4 nano sheet	3.5wt%	ORR	21
Fe SAs–N/C-20	Fe–N4	Fe Pc, ZIF-8	0.20wt%	ORR	22
Fe–CBDZ	Fe–Nx	Fe (NO3)3·9H2O, CBDZ		ORR	23
Fe–N–C	Fe–N4	Fe3+, ZIF-8	1.5wt%	ORR	32
Fe–N–C-950	Fe–N4	Fe (NO3) 3, ZIF-8	0.137wt%	ORR	33
Fe Pc/Ti3C2Tx	Fe–N4	Fe Pc, Ti3C2Tx	4.09wt%	ORR	25
PpPD–Fe–C	Fe–N6	p-Phenylenediamine, ferric chloride, carbon black	12.08wt%	ORR	26
Fe3+–N–C	Fe–Nx	FeCl2, ZIF-8	2.6wt%	CO2RR	34
Fe/NG-750	Fe–N4	Graphene oxide, FeCl3	0.52wt%	CO2RR	20
ISAS–Fe/NC	Fe–N4	C34H32FeN4O4, ZIF-8	4.2wt%	NRR	19
Fe1–N–C	Fe–N4	FeCl2·4H2O, meso-tetra (4-carboxyphenyl) porphine tetramethyl ester	4.51wt%	NRR	35
Fe–N–C	Fe–Nx	Glucose, dicyandiamide, FeCl2·4H2O	0.26wt%	ECL	36
Fe/GD		Graphdiyne, FeCl3	0.680wt%	HER	8