fig3

Figure 3. Cross-sectional SEM images comparing the partial and full Au skins. (A) Partial Au skin: 300 µm p-type Bi₂Te₃ particles with 2.76 wt.% Au skin; (B) full Au skin: 300 µm p-type Bi₂Te₃ particles with 3.86 wt.% Au skin. SEM: Scanning electron microscopy.