Loofah sponge composite with Fe3+-tannic acid phenolic network for off-grid areas and emergency scenario of use water disinfection and photothermal evaporation

The treatment of emergency water is achieved by a portable infrared flashlight. • A novel photothermal FTS-LS was constructed using loofah sponge for the first time. • FTS-LS shows excellent structural stability and photothermal conversion performance. • Bio-based FTS-LS combines good biosafety with biodegradability. Access to uncontaminated water is a fundamental prerequisite for ensuring the life and health. However, developing green, effective, and user-friendly water disinfection technologies for off-grid areas and emergency situations (e.g., natural disasters, outdoor activities) remains a significant challenge. In this study, a novel and convenient water disinfection composite material was prepared by constructing the Fe 3+ -tannic acid metal-phenolic network in 3D porous loofah sponge (LS). The prepared Fe 3+ -tannic acid/sodium alginate (SA) /loofah sponge (FTS-LS) maintains high macroscopic structural stability and surface functional filler integrity even under an external force exceeding 1641 times its own weight and after 200 cycles of manual friction. Furthermore, it exhibits excellent and stable photothermal conversion performance and favorable photothermal water evaporation rates under near-infrared (NIR) light irradiation. Notably, FTS-LS has outstanding photothermal synergistic antibacterial performance (approximately 99%), proving effective even in complex water sources such as field ponds and farmland runoff. This great biosafe and biodegradable FTS-LS composite material is expected to become a portable water disinfection device and photothermal evaporators suitable for off-grid areas and emergency scenarios. Download: Download high-res image (182KB) Download: Download full-size image