Ferns on a Nickel Foil
Single-atom thick crystals of boron nitride cover nickel foil in this image. Despite being so thin, the boron nitride protects the nickel from oxidation, creating strong contrast between coated and uncoated regions. The 2D material’s structure leaves dark, fern-like patterns on the metal’s surface. The nickel oxide appears white and rough compared to the smooth, darker surfaces of nickel covered by hexagonal boron nitride. Underlying nickel grains can be seen from their merging boundaries in the top left of the image. The image was taken by a scanning electron microscope in secondary electron imaging mode. Micrograph dimensions are approximately 100µm by 75µm.