A polydopamine modified floral foam three-dimensional water evaporator for desalination via a directional self-assembly technology

Here, we prepared a water evaporator modified with polydopamine (PDA) using the directional self-assembly technology. The evaporator has a porous structure that can transport water through strong capillary action. With the modification of PDA, its light absorption rate is higher than 86% in the full spectral range of 200–2500 nm. Under one-sun irradiation, the water evaporator has a high evaporation rate (3.51 kg m−2h−1) and light-to-heat conversion efficiency (94.5%). Moreover, the evaporator has good salt suppression performance, and there is no salt crystallization during the evaporation process. It is an environmentally friendly, efficient, and reliable solar steam generator used for desalination and wastewater purification.