2.2 Solar Vapour Generation under 1 Sun
Ultraviolet-visible near-infrared (UV-Vis-NIR) measurements (Figure 3a)
display excellent solar absorption properties of
MF@HPB-PPyn-OA. The MF@PPy10-OA has good
light absorption in the spectral range of 200-2500 nm because of the PPy
coverage on MF. The absorption of MF@HPB-PPy10 is
visibly strengthened in the Vis-NIR region when the HPB component with
excellent light absorption properties in Vis-NIR is introduced. Based on
the advantages of the 3D porous structure of
MF@HPB-PPy10-OA and the stability and homogeneity of the
HPB-PPy10-OA coating, MF@HPB-PPy10-OA
demonstrates nearly
complete light absorption (95.3%, weighted under AM 1.5G), presenting
excellent photothermal conversion potential. In Figure 3b, the surface
temperature of MF@HPB-PPy10-OA in the dry state rapidly
increases to 89.5 oC and remains stable within 3 min
under 1 sun. The photothermal conversion capacity of
MF@HPB-PPy10-OA is obviously higher than that of MF,
MF@PPy10-OA and MF@HPB-PPy10, which is
attributed to the superiority of HPB composition (Figure S6) and the
unique surface structure. When MF@HPB-PPy10-OA is in the
wetted state, the temperature steady-state value of surface is slightly
lower than that of MF@PPy10-OA and
MF@HPB-PPy10 (Figure 3c). Specifically, the absorbed
sunlight is applied to the photothermal water evaporation, thus the
lower temperature steady-state value implies stronger evaporation
efficiency. The photothermal water evaporation experiments further
confirm the above results. Before executing the water evaporation,
MF@HPB-PPyn-OA improves the evaporation area and the
internal temperature of structure by tailoring the edges into an
orthogonal prismatic table structure (Figure S7 and Figure S8c). As
displayed in