Preparation of polypropylene with photothermal conversion and hydrophilicity by one-step impregnation for efficient interfacial water evaporation

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Physicochemical and engineering aspects, 2024-01, Vol.681, p.132850, Article 132850
• Main Authors: Li, Hao, Zhang, Zhaoyang, An, Mengjie, Bai, Gang, Duan, Chao, Liu, Yiping, Lu, Ming
• Format: Article
• Language: English
• Subjects: Hydrophilic modification; Interfacial water evaporation; Melt-blown polypropylene nonwovens; Photo-thermal conversion
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2023.132850

Solar-driven interfacial water evaporation is a technology that is currently attracting significant interest for tackling freshwater scarcity. However, the creation of porous membranes with photothermal conversion and hydrophilicity remains a challenging task. This study utilizes melt-blown polypropylene nonwoven (PP), a substrate with high porosity, low cost and high yield, to prepare evaporation membranes exhibiting photothermal conversion properties. The PP surface was treated with a one-step impregnation method to produce both shell and nanoparticles containing MnO2−x. The addition of MnO2−x grants the PP membranes both photothermal conversion and hydrophilicity simultaneously. Sunlight absorption efficiency of PP membranes covered with MnO2−x (M-PP) is 85.83%, and its hydrophilicity and porosity enable it to form an ultra-thin layer of water during evaporation, promoting rapid escape of vapors. Evaporation rate of M-PP membranes reach 1.02 kg m−2 h−1, much higher than that of PP and bulk water. In addition, M-PP membranes have excellent corrosion resistance, which is potentially valuable in treating wastewater and desalinating seawater. [Display omitted] •Modified PP has both photothermal conversion properties and hydrophilic properties.•High yield, low cost, and easy access to PP as a base material.•M-PP membranes exhibit excellent performance in water evaporation, photothermal conversion, and wastewater treatment.•M-PP membranes have excellent corrosion resistance.