fig4

Figure 4. (A) Schematic diagram of the preparation of MoS₂ films with different arrangements; SEM images of MoS₂ films arranged in (B) horizontally aligned, (C) hybrid aligned, and (D) vertically aligned; (E) Comparison curves between the responses of MoS₂ films in various arrangements to various NO₂ concentrations^[61]. Copyright 2015, ACS Publications; (F) Schematic diagram of the growth process for both solid and hollow hierarchical MoS₂ microspheres; (G) Response curves of MoS₂ spheres with different structures to different concentrations of NO₂ at 150 °C^[59]. Copyright 2019, Elsevier; (H) Response mechanism of WS₂_Co-N-HCNCs to NO₂; (I) Real-time response curves of WS₂_Co-N-HCNCs to NO₂ after different heat treatments; (J) Adsorption rate constants (kads) and desorption rate constants (kdes) of WS₂_Co-N-HCNCs after different heat treatments^[60]. Copyright 2018, John Wiley and Sons. SEM: Scanning electron microscopy.