Same materials, bigger output: A reversibly transformable 2D-3D photothermal evaporator for highly efficient solar steam generation
Same materials, bigger output: A reversibly transformable 2D-3D photothermal evaporator for highly efficient solar steam generation
复制标题
相同的材料，更大的产量：可逆转换的 2D-3D 光热蒸发器，用于高效太阳能蒸汽发电
DOI：
10.1016/j.nanoen.2020.105477
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发表时间：
2021-01-01
期刊：
影响因子：
17.6
通讯作者：
Xu, Haolan
中科院分区：
文献类型：
--
作者：
Wang, Yida;Wu, Xuan;Xu, Haolan
利用太阳能-热能通过界面太阳能蒸汽发生来驱动海水淡化是清洁水供应的可持续战略。由于光热材料和蒸发器是太阳能蒸汽发生过程中高效光热转换和水分蒸发的关键平台，因此光热材料和蒸发器结构的合理设计非常重要。在这项工作中，还原氧化石墨烯和纤维素海绵为基础的可转换光热蒸发器，可以可逆地切换之间的二维平面和三维螺旋结构的设计。虽然材料的质量和体积相同，但由于蒸发表面积的增加和优化的水输送，从2D到3D蒸发器的简单结构转换显著提高了蒸发速率。此外，数值模拟表明，3D螺旋结构能够有效地利用对流来充分激活和增强其表面上的蒸发，从而导致更高的蒸发速率（高达4.35 kg m（-2）h（-1）），这是2D平坦结构的蒸发速率的185.9%。此外，3D螺旋结构可以容易地转换回2D平面结构，以便于存储。因此，这项工作提出了一种有效的策略，以尽量减少光热材料的使用，同时实现更高的蒸发率，为实际的清洁水生产。
Using solar-thermal energy to drive seawater desalination via interfacial solar steam generation is a sustainable strategy for clean water supply. Since photothermal materials and evaporators serve as key platforms for efficient light-to-heat conversion and water evaporation during solar steam generation, the rational design of the structure of photothermal materials and evaporators is important. In this work, a reduced graphene oxide and cellulose sponge-based transformable photothermal evaporator which can reversibly switch between a 2D flat and a 3D spiral structure is designed. Although the mass and volume of the materials are identical, simple structural transformation from a 2D to a 3D evaporator significantly enhances the evaporation rate due to an increase in the evaporation surface area and optimized water transportation. In addition, numerical simulations demonstrate that the 3D spiral structure is able to effectively take advantage of convective flow to fully activate and enhance evaporation on its surfaces, resulting in a much higher evaporation rate (up to 4.35 kg m(-2) h(-1)), which is 185.9% of the evaporation rate of the 2D flat structure. Furthermore, the 3D spiral structure can be easily transformed back to the 2D flat structure for easy storage. Thus, this work presents an effective strategy to minimize the use of photothermal materials while simultaneously achieving higher evaporation rates for practical clean water production.