Figure 1: Scheme and TEM images of Ni–B membrane growing process.

(a) Scheme illustrating the structural transformation from PtNi3 octahedron to Pt-Ni/Ni–B composite. TEM images of (b) initial PtNi3 octahedrons and (c) Pt-Ni/Ni–B composite. (d) High-angle annular dark-field scanning transmission electron microscope (HAADF-STEM) image of Pt-Ni/Ni–B composite. Scale bars, 50 nm.