Ginseng-Bioinspired 3D Photothermal Evaporator for Efficient Seawater Desalination Using Conjugated Microporous Polymer

Photothermal conversion technology presents a promising approach for harnessing solar energy to facilitate seawater desalination. However, salts will accumulate on the surface of the photothermal conversion structure during seawater desalination, which hinders solar energy absorption. Meanwhile, the photothermal conversion structure directly immersing in a large water body results in a large heat dissipation loss. Both factors impair solar energy conversion and water steam generation. To address the issues, inspired by a ginseng plant (with a trunk-to-branch water supply system), a 3D cotton-based photothermal evaporator with tunable water supply is facilely designed herein via simple cloak-weaving of a porphyrin-based conjugated microporous polymer (PPCMP) as the photothermal conversion material. The as-designed 3D cloak-like photothermal evaporator achieves an equilibrium between the water supply flux and evaporation rate via optimizing PPCMP weaving and the water path. As a result, a high evaporation rate of 2.81 kg m-2 h-1 and photothermal conversion efficiency of 155% are obtained under 1 sun illumination. The findings underline the importance of 3D porous organic polymer-based fabrics as effective media for harnessing solar energy and highlight their potential for seawater desalination. This work designs a conjugated microporous polymer composite cotton-based photothermal evaporator inspired by a ginseng plant, which has a high evaporation rate of 2.81 kg m-2 h-1 and a photothermal conversion efficiency of 155%, underlining the importance of 3D porous organic polymer-based fabrics as effective media for harnessing solar energy and highlighting their potential for seawater desalination. image