PTFE-based composite nanofiber membranes for solar-driven interfacial water evaporation

Photothermal conversion is an environmentally friendly and promising technology for producing freshwater. Solar thermal conversion provides a simple and scalable method for photothermal conversion and purifying water. However, its practical application requires more efficient, robust, and photothermal functional materials. In this research, the PTFE-based composite nanofiber membrane was prepared by electrospinning, hot-pressing, and subsequent sintering treatments to improve the photothermal conversion. The results demonstrated that the prepared PTFE-based membrane has ~91.4% photothermal conversion efficiency under one sun illumination (~2.3 kg∙m 2 ·h −1 ). The excellent solar-thermal conversion efficiency of the PTFE-based membrane is contributed to their unique membrane surface microstructure and chain transformation after sintering treatment. In addition, the stress strength and strain of the PTFE-based composite membrane were 11.5 MPa and 482%, respectively. The excellent mechanical and photothermal conversion of PTFE-based composite fiber membranes offer its promising application in interface evaporator.