Morning Glory-Inspired Biomimetic Water Purification Device with a Dry Chimney for Efficient Solar-Thermal Desalination and Simultaneous Catalytic Degradation of Organic Pollutants
Although solar steam generation is effective in evaporating water and seawater under solar light irradiation, it is ineffective in purifying wastewater and seawater with organic pollutants. Herein, a morning glory-shaped water purification device with a dry chimney (pistil) is designed for simultaneous solar-thermal evaporation of water and catalytic degradation of organic pollutants therein, which is fabricated by decorating Au/CoFe2O4/carbon nanotube functional components on a hydrophilic and porous bamboo fabric substrate. Au and CoFe2O4 are capable of forming Mott–Schottky heterostructures to create a stable built-in electric field and promote the separation of electron–hole pairs, thereby facilitating the activation of potassium peroxymonosulfate to generate reactive oxygen species and achieving a high catalytic degradation rate constant of 0.222 min–1 under 1-sun irradiation. Crucially, the chimney of the bionic morning glory structure benefits the continuous supply of dry air and creates airflow circulation, thereby reducing the humidity and increasing the evaporation rate by facilitating the escape of saturated water vapor from the evaporator, achieving a high water evaporation rate of 3.21 kg m–2 h–1 under 1-sun irradiation. A total water purification rate as high as 28.21 kg m–2 h–1 is realized by the simultaneous solar-thermal evaporation of wastewater and catalytic degradation of organic pollutants therein. The integration of catalytic degradation and solar steam generation enables an efficient protocol for purifying wastewater and seawater with organic pollutants.