Self-Healing Hydrophilic Porous Photothermal Membranes for Durable and Highly Efficient Solar-Driven Interfacial Water Evaporation

Abstract

It is highly desirable to develop a solar-driven interfacial water evaporator with a self-healing ability and highefficiency water evaporation performance for water distillation and desalination, but it is still considerably challenging. Herein, by exploiting the advantages of the self-healing hydrophilic polymer, a self-healing hydrophilic porous photothermal (SHPP) membrane is fabricated by the curing of a mixture of a self-healing hydrophilic polymer, carbon black, and NaCl, followed by the removal of NaCl in water. As the SHPP membrane can simultaneously serve as a photothermal layer and water transportation channel, a solar-driven interfacial evaporator can be readily fabricated by the assembly of the SHPP membrane with a polyethylene foam. The SHPP membrane-based evaporator exhibits a water evaporation rate of 1.68 kg m -2 h -1 and an energy efficiency of 97.3%. These values are superior to those obtained using solar-driven interfacial evaporators with a selfhealing capability. Notably, by reforming hydrogen bonds between fracture surfaces, the SHPP membrane can regain its structural integrity after breaking, making the SHPP membrane-based evaporator the first evaporator that can completely and repeatedly heal water evaporation capacity after physical damage. Herein, the potential of SHPP membranes for developing stable, long-lasting, and high-efficiency solar-driven interfacial water evaporators is highlighted.

Overflow Control for Sustainable Development by Superwetting Surface with Biomimetic Structure

“…On 22 March 2021, World Water Day raised awareness of the global water crisis and appealed to valuing water to support the achievement of Sustainable Development Goal 6: availability and sustainable management of water and sanitation for all by 2030 . To address this issue and achieve the goal of carbon peak by 2030 and carbon neutralization by 2060, researchers focused on finding sustainable sources of freshwater by harvesting water from atmospheric fog, ,,,− producing water from saline water desalination, ,,,,− and wastewater treatment. ,,,− …”

“…In recent years, with the emergence of biomimetic interface research, bioinspired materials with superwettabilities and topological structures were fabricated and used to control liquid–solid interfacial action. ,,− Superwettability as a new scientific discovery and a fully commercialized technology has been listed as one of the top ten emerging technologies of chemistry projects in 2021, which possesses a great capacity to contribute to the well-being of society and the sustainability of the earth, and open new opportunities in chemistry and beyond . Research on fundamental interface problems has gradually shifted from static to dynamic ,, such as liquid impact, transport, breakup and dripping, bursting, etc., − from kinetic processes to thermodynamic processes such as icing and melting, , frosting, dewing, thermal cooling, evaporation and crystallization, ,,,, cooling crystallization, and boiling. , In nature, many organisms can survive under harsh conditions via skillfully manipulating liquid overflow using their unique surface structures. In addition, the overflow phenomenon is common in many applications ranging from macroscale water jets, microfluidic chips, to nanoscale spinning.…”

“…97,270,334−336 Superwettability as a new scientific discovery and a fully commercialized technology has been listed as one of the top ten emerging technologies of chemistry projects in 2021, which possesses a great capacity to contribute to the well-being of society and the sustainability of the earth, and open new opportunities in chemistry and beyond. 337 Research on fundamental interface problems has gradually shifted from static to dynamic 97,136,338 such as liquid impact, transport, breakup and dripping, bursting, etc., 339−344 from kinetic processes to thermodynamic processes such as icing and melting, 345,346 frosting, 347 dewing, 348 thermal cooling, 349 evaporation and crystallization, 45,89,204,206,350 cooling crystallization, 351 and boiling. 352,353 In nature, many organisms can survive under harsh conditions via skillfully manipulating liquid overflow using their unique surface structures.…”

Solar-driven interfacial evaporation for water treatment: advanced research progress and challenges

“…In 1 M H 2 SO 4 or NaOH wastewater, the ER of SHCSC was maintained at 2.2 kg m −2 h −1 . Xu et al 53 reported the preparation of self-healing hydrophilic porous photothermal membranes (PU 20 /CB 0.5 /NaCl 5 membranes), which exhibited an ER of 1.68 kg m −2 h −1 . After soaking in 1 wt% CH 3 COOH (pH = 2.8) and 1 wt% Na 2 CO 3 (pH = 11.7) solution for 10 days, the porous structure of the material was stable.…”

Rational Design of Biomass-Derived Composite Aerogels for Solar-Driven Seawater Desalination and Sewage Treatment

“…Given the abundance and sustainability of sunlight, harnessing solar energy to produce freshwater has drawn increasing attention over the past years. − Volumetric evaporation or nanofluid systems would typically lead to severe heat loss below the water–air interface . In comparison, the localized solar–thermal conversion in the interfacial evaporation process simultaneously applies most of the heat to the liquid–vapor phase transition and improves the evaporation efficiency, − which is promising in the field of water purification.…”