fig2

Figure 2. SEM images of pristine MoS₂ (A), TEM images of pristine MoS₂ under different magnifications (B, C) and MoS₂ with different doping concentrations of Ni: S1 (D), S2 (E), S5 (F), S10 (G), S20 (H). SEM: Scanning electron microscope; TEM: transmission electron microscope.