Tannic Acid‐Iron Nanozyme Coating Enabled Anti‐Biofouling 3D Silk Fibroin Scaffold for Stable Solar Evaporation

Solar interfacial evaporation has been intensively studied for sustainable clean water production. In recent years, three‐dimensional (3D) and salt‐rejection design have been introduced, to improve the evaporation rate and stability in treating natural water. However, the biofouling resistance is also highly demanded for stable evaporation, due to the large‐scale distribution of bacteria in various source of water. Herein, we develop an anti‐biofouling 3D silk fibroin scaffold with a tannic acid‐iron coating (SF‐TA‐Fe) for efficient and stable solar evaporation. This TA‐Fe coating enables high photothermal conversion efficiency and nanozyme‐based antibacterial capability. Under 1 sun, the scaffold achieved a high evaporation rate of 2.71 kg m −2 h −1 . After treating in bacterial suspensions, the 3D SF‐TA‐Fe scaffold maintains native porous structure without channels clogging. In contrast, the scaffold without nanozyme behaviour suffers biofouling formation and pores clogging. Accordingly, the 3D SF‐TA‐Fe scaffold maintains the evaporation rates of 2.47–2.52 kg m −2 h −1 , which showing 91.1–93.0% performance of the fresh prepared scaffold. In contrast, the scaffold without nanozyme‐catalytic treatment suffers significant decline in evaporation rate (reduced to 1.90–2.13 kg m −2 h −1 ), which merely exhibit 70.1–78.6% original performance, only after 5 days incubation in bacterial‐contaminated water. In addition, the scaffold exhibits stable outdoor and desalination performance.