Abstract With the aggravation of water resource shortage, solar-driven interface seawater desalination is considered to be one of the most promising ways to solve the water crisis. However, there still exist enormous difficulties in preparing efficient interface evaporators with self-floating and self-cleaning properties. Herein, we demonstrate a scalable bi-layered bacterial cellulose (BC) biofoam evaporator, in which the CuS/BC composite material is used as the photothermal conversion layer and the regenerated BC biofoam is employed as the water transport and thermal insulation layer. The optimized evaporation rate is as high as 1.44 kg m−2 h−1, and the evaporation efficiency reaches to 83.5%, which are higher than the performances of most reported BC-based solar evaporators. Besides, the bi-layered BC biofoam exhibits the self-floating ability which can keep a stable long-term floatability more than 6 weeks, and displays excellent self-cleaning ability which can clean the salt of 2 g within 120 min at a circle diameter of 4.8 cm. The solar evaporator simultaneously has photocatalytic purification. The lightweight, portable, self-floating and self-cleaning solar evaporator with photocatalytic performance offer possibilities for solar-powered water treatment, dyeing wastewater purification and other advanced solar thermal applications.

中文翻译：

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可扩展、自清洁和自漂浮的双层细菌纤维素生物泡沫，用于具有光催化净化的高效太阳能蒸发器

摘要 随着水资源短缺的加剧，太阳能驱动界面海水淡化被认为是解决水资源危机最有前景的方法之一。然而，制备具有自漂浮和自清洁特性的高效界面蒸发器仍然存在巨大的困难。在此，我们展示了一种可扩展的双层细菌纤维素 (BC) 生物泡沫蒸发器，其中 CuS/BC 复合材料用作光热转换层，再生 BC 生物泡沫用作水传输和隔热层。优化后的蒸发率高达 1.44 kg m-2 h-1，蒸发效率达到 83.5%，高于大多数报道的基于 BC 的太阳能蒸发器的性能。除了，双层BC生物泡沫具有自漂浮能力，可保持稳定的长期漂浮能力6周以上，并表现出优异的自洁能力，可在120分钟内清洗4.8圈直径的2g盐分厘米。太阳能蒸发器同时具有光催化净化。具有光催化性能的轻质、便携、自漂浮和自清洁太阳能蒸发器为太阳能水处理、印染废水净化和其他先进的太阳能热应用提供了可能性。