Porous Hydrogel Photothermal Conversion Membrane to Facilitate Water Purification

Solar water purification technology is one of the most potent methods to obtain freshwater due to its low cost and non-polluting characteristics. However, the purification efficiency is limited by the high ion concentration, organic pollution, and biological pollution during the actual water purification process. Here, we report a porous hydrogel membrane (Fe/TA-TPAM) for the purification of high ion concentration and contaminated water. The hydrogel membrane exhibits good light absorption and photothermal conversion ability, which shows high evaporation rates (1.4 kg m–2 h–1) and high solar efficiency for seawater. Furthermore, with the introduction of tannic acid (TA) and Ti3C2 MXenes, the Fe/TA-TPAM hydrogel membrane exhibits satisfied purification properties for organic-contaminated and biologically contaminated water. The excellent purification effect of Fe/TA-TPAM under light not only confirms the rationality of the hydrogel porous design and in situ generation of photosensitizer in improving the photothermal performance but also provides a novel strategy for designing advanced photothermal conversion membranes for water purification.