Dong Xiangyang, Cao Leitao, Si Yang, Ding Bin, Deng Hongbing
Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Laboratory of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, 430079, China.
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Textiles, Donghua University, Shanghai, 201620, China.
Adv Mater. 2020 Aug;32(34):e1908269. doi: 10.1002/adma.201908269. Epub 2020 Jul 19.
The emerging solar desalination technology is considered as one of the most promising strategies to ensure water security. However, with the proceeding of solar desalination, salt crystallization on the surface of solar evaporators caused by increasing salinity of seawater will result in a decrease in the evaporation rate. Thus, it is still challenging to fabricate solar evaporators with superior salt resistance. In this work, elastic ceramic-based nanofibrous aerogels with a cellular architecture are fabricated by the combination of electrospinning and fiber freeze-shaping technologies, which are composed of vertically aligned vessels and porous vessel walls. Under the action of convection and diffusion promoted by this unique cellular architecture, the aerogels exhibit a superior salt-resistance without any salt crystals on the surface of aerogels even in 20% brine and under 6-sun irradiation. Moreover, by virtue of the synergistic effect of the promising structure and light absorbance of carbon nanotubes, aerogels possess a high light absorbance of up to 98% and excellent evaporation performance achieving 1.50 kg m h under 1-sun irradiation. This work may provide a fascinating avenue for the desalination of seawater in a salt-resistance and efficient manner.
新兴的太阳能海水淡化技术被认为是确保水安全最具前景的策略之一。然而，随着太阳能海水淡化的进行，海水盐度增加导致太阳能蒸发器表面盐结晶，这将导致蒸发速率下降。因此，制造具有优异耐盐性的太阳能蒸发器仍然具有挑战性。在这项工作中，通过静电纺丝和纤维冷冻成型技术相结合制备了具有蜂窝结构的弹性陶瓷基纳米纤维气凝胶，其由垂直排列的容器和多孔容器壁组成。在这种独特的蜂窝结构促进的对流和扩散作用下，气凝胶表现出优异的耐盐性，即使在20%的盐水中并在6倍太阳光照射下，气凝胶表面也没有任何盐晶体。此外，由于碳纳米管有前景的结构和吸光性的协同作用，气凝胶具有高达98%的高吸光率和优异的蒸发性能，在1倍太阳光照射下实现1.50 kg m² h⁻¹ 的蒸发速率。这项工作可能为以耐盐且高效的方式进行海水淡化提供一条引人入胜的途径。
