Fig. 2: Preparation and characterization of DSEs.

a 3D printed spherical and Dyson sphere-like base structures. b Schematic diagram of the photothermal hydrogel coating processes. SEM images of the surface structure of the (c) 3D printed base, (d) High-magnification coated photothermal hydrogel surface, (e) Low-magnification coated photothermal hydrogel surface, and (f) SEM images of the cellulose in photothermal hydrogel.