Figure 4

(a) Digital photos of a FTO glass substrate (left), a flower-like MoS₂ nanosheet film on FTO (middle), and a large size MoS₂ nanosheet film on FTO (right). Each substrate is about 1 × 2 cm² in dimension. (b) Schematic representation of the flower-like structure in ammoniated MoS₂ ultrathin nanosheets.