Fig. 1. Processing process of the bumpy Janus film. (a) Superhydrophilic film; (b) superhydrophobic film; (c) Janus film; (d) bumpy Janus film

Fig. 2. Condensation analysis of the bump structure. (a) Diffuse flux intensity distribution of the bump^[2]; (b) influence of radius on the droplet condensation; (c) droplet growth on bump of different sizes

Fig. 3. SEM images of the surface of the Janus film and the inside of the tapered hole. (a) Aluminum foil thickness; (b) bottom surface topography; (c) magnified view of the bottom surface tapered hole; (d) top surface topography; (e) magnified view of the top surface tapered hole; (f) cross section of the tapered hole; (g) top of the tapered hole; (h) bottom area of the tapered hole; (i) fog collection model

Fig. 4. Condensation law on the surface of different Janus film. (a) Flat Janus film; (b) bump Janus film

Fig. 5. Measurement of fog collection of bumpy Janus film. (a) Effect of bump size on fog collection; (b) fog collection results of the flat Janus film and bump Janus film

Fig. 6. Change curve of wettability