Fig. 2: STEM characterization of the MgAg_0.97Sb_0.99-0.02InSb composite.

A HAADF-STEM image. B Corresponding EDS mapping of (A). C HAADF image of the area enclosed by the red box in (A), with InSb and Ag₃In nanoprecipitates outlined by white and orange dashed lines, respectively. D, E High-magnification TEM images from (C), showing InSb-MgAgSb and InSb-Ag₃In phase boundaries. The corresponding FFT images were indexed as MgAgSb (D1), InSb (D2 and E1), and Ag₃In (E2), respectively. F Atomic-resolution HAADF image of the InSb secondary phase along the [111] crystallographic direction. G, H Magnified views of (F) with the corresponding atomic structural model.