School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo City, Shandong Province 255049, PR China.
Department of Technology Manager, Shandong Weigao Group Medical Polymer CO., Limited, Weihai 264210, PR China.
J Colloid Interface Sci. 2018 Nov 15;530:274-281. doi: 10.1016/j.jcis.2018.06.081. Epub 2018 Jun 27.
It is well recognized by the scientific community that the fog can be deposited and transported on asymmetric surfaces, thus numerous efforts have been made to create such surfaces. However, it is still challenging to design a surface capable of fast deposition and rapid transportation simultaneously. Herein, inspired by the asymmetric structure of cactus spines and the cooperative hydrophilic/hydrophobic regions of desert beetles, a superhydrophilic-hydrophobic integrated conical stainless steel needle (SHCSN) is fabricated by a facile method. This integrated needle surface combines the merits of the fast deposition of fog on hydrophobic region and then rapid transportation on superhydrophilic surface. The droplet average transportation velocity on SHCSN is greater than other types of surfaces because of large Laplace pressure and self-driven phenomenon at its superhydrophilic-hydrophobic boundary. The best fog harvest efficiency was realized by optimizing the length of the hydrophobic region using theoretical modeling and experimental exploration, whereas the robust superhydrophilic needle surface induced the increase of collection time. This SHCSN was realized to be more efficient in fog collection than uniform superhydrophilic, uniform hydrophobic/superhydrophobic needle surfaces.
科学界早已认识到雾滴可以在不对称表面上沉积和输运，因此人们已经做出了许多努力来创造这种表面。然而，设计出一种既能快速沉积又能快速输运的表面仍然具有挑战性。受仙人掌刺的不对称结构和沙漠甲虫亲/疏水区域协同作用的启发，通过一种简便的方法制备了超亲水-疏水一体化锥形不锈钢针（SHCSN）。这种集成针表面结合了雾滴在疏水区快速沉积和在超亲水表面快速输运的优点。由于超亲水-疏水区的大拉普拉斯压力和自驱动现象，SHCSN 上液滴的平均输运速度大于其他类型的表面。通过理论建模和实验探索优化疏水区的长度，实现了最佳的雾收集效率，而坚固的超亲水针表面增加了收集时间。与均匀超亲水、均匀疏水/超亲水针表面相比，这种 SHCSN 实现了更高效的雾收集。
