Low‐Cost, Scalable, and Reusable Photothermal Layers for Highly Efficient Solar Steam Generation and Versatile Energy Conversion
Xiaoli Shan, Aiqing Zhao, Yawen Lin, Yujing Hu, Yunsong Di, Cihui Liu, Zhixing Gan
Abstract
Abstract Solar steam generation (SSG) based on the photothermal effect has been considered to be a promising avenue for freshwater production. However, the fabrication of highly‐efficient photothermal layers, at large‐scale and low‐cost is still a challenge, hindering practical applications. Herein, it is demonstrated that carbonized towel‐gourd sponges (CTGS) are excellent photothermal materials. And a capillarity‐driven interfacial self‐coating method is developed to prepare the super‐hydrophilic CTGS/paper photothermal layer. The SSG device based on the CTGS/paper exhibits a high evaporation rate of 1.53 kg m −2 h −1 with an efficiency of 95.9% under 1 sun irradiation. The high evaporation rate only slightly reduces when confronting the diverse and complex practical SSG conditions, such as seawater and waste water. Moreover, CTGS/paper has the advantages of simple preparation, recyclablability, low‐cost (≈4 $ per m 2 ), high‐efficiency, flexibility, and scalability, which are the important prerequisites for promoting SSG techniques for industrialization and practical applications. In addition, the versatile energy conversion ability of the CTGS/paper is also demonstrated. Assisted by the photothermal effect of CTGS/paper, solar energy is converted to mechanical energy and electricity.