Flexible and Efficient Solar Thermal Generators Based on Polypyrrole Coated Natural Latex Foam for Multimedia Purification

Abstract

Solar evaporation has emerged as a facile and attractive technology for clean water production, desalination, and organic solvent purification by virtue of abundant solar energy. However, developing a high-performance, environment friendly, and scalable solar evaporator remains a significant challenge. Herein, a one-step, low-cost, and easy-to-manufacture synthesis of a three-dimensional macroporous solar steam generator is reported based on polypyrrole coated natural latex (PPy-NL) foam, offering a sustainable solution to the ever-growing issues of the energy and water crises. The as-prepared foam exhibits good wettability, acid and alkali resistance, high mechanical strength, low thermal conductivity (0.2257 W m–¹ K–¹) and excellent light absorption of ∼95% owing to the introduction of PPy coating. Among polymer photothermal materials, PPy-NL foam gives a vapor generation rate of 1.76 kg m–² h–¹ with a superb solar thermal conversion efficiency of 98% under 1 sun illumination. Furthermore, PPy-NL foam can be directly used to purify various types of wastewater and organic solvent with a high rejection of ions (nearly 100%), oil, and dye. This simple fabrication process with renewable polymer resources and photothermal materials provides a fundamental guidance and practical application value toward developing high-performance solar evaporation technologies for remote areas and individuals.