Fig. 2: Synthesis scheme and structural characterizations of Cr-Ni3S2.

a Schematic illustration of the synthesis of Cr-Ni3S2. b XRD patterns of Cr-Ni3S2 and Ni3S2. c TEM image of Cr-Ni3S2. d HADDF-STEM image and TEM mapping images of Cr-Ni3S2. e AC HAADF-STEM image, f False-color HAADF-STEM image and g corresponding EELS spectra in region I of (e) for Cr-Ni3S2. Source data are provided as a Source Data file.