Fig. 2: Surface appearance and internal structure of WBD materials.

a–c HRTEM images of the WBD specimen. d, e SEM-EDS images of WBD (5,000× magnification). f Elemental mapping results for WBD.
a–c HRTEM images of the WBD specimen. d, e SEM-EDS images of WBD (5,000× magnification). f Elemental mapping results for WBD.