Fig. 1: Electron spectroscopy of the NiCuCr/C catalysts.

a TEM image of NiCuCr/C. The bottom left insert is a statistical histogram of the size of the particles. The upper right insert is the selected area electron diffraction pattern of NiCuCr/C. b The XRD pattern of NiCuCr/C. c HAADF-STEM image of a NiCuCr nanoparticle. Right enlarged areas show the lattice fringes. d HAADF-STEM elemental mapping image of a NiCuCr nanoparticle.