Fig. 2: TEM and XRD characterization of Fe-Co DACs.

a TEM image of Fe-Co DACs. b XRD patterns of Fe-CoDACs and Fe(Co) SACs. c Aberration-corrected HAADF-STEM image of Fe-Co DACs and some Fe-Co diatomic sites are highlighted by red circles (The red circles 1,2 and 3 are partially enlarged on the right). d Intensity profiles of the three sites in c.