Multifunctional Cotton Fabric–Based Solar Evaporator With Excellent Photocatalytic Degradation and Oil‐Water Separation

As a promising solution to the global water scarcity crisis, solar interfacial evaporation has been applied to seawater desalination. However, the manufacturing of solar evaporators that simultaneously demonstrate high efficiency and high pollution tolerance remains a challenge. To address this issue, we prepared superhydrophobic cotton fabric with both photocatalytic degradation and photothermal conversion functions. This cotton fabric‐assembled evaporator exhibits excellent photothermal conversion performance, achieving an evaporation rate of 1.74 kg·m −2 ·h −1 under 1 Sun illumination. The cotton fabric achieved a 96.4% degradation rate of rhodamine B dye within 1 h under visible light irradiation. Additionally, the cotton fabric exhibited an oil flux of 18420.58 L·m −2 ·h −1 for dichloromethane, with an oil‐water separation efficiency exceeding 99%. This work provides an innovative solution for the treatment of complex oily wastewater, which contains salt and dyes.