Enhancing the Long-Term Robustness of Dropwise Condensation on Nanostructured Superhydrophobic Surfaces by Introducing 3D Conical Microtextures Prepared by Femtosecond Laser
Enhancing the Long-Term Robustness of Dropwise Condensation on Nanostructured Superhydrophobic Surfaces by Introducing 3D Conical Microtextures Prepared by Femtosecond Laser
复制标题
通过引入飞秒激光制备的 3D 圆锥形微观纹理来增强纳米结构超疏水表面上滴状冷凝的长期鲁棒性
DOI：
10.1002/admi.202000997
复制
发表时间：
2020-09-13
影响因子：
5.4
通讯作者：
Xie, Xiaozhu
中科院分区：
文献类型：
--
作者：
Long, Jiangyou;Zhou, Peiyang;Xie, Xiaozhu
实现可持续的滴状冷凝对于仿生超疏水表面在相变传热领域的工业应用仍然是一个挑战。在这项工作中，利用飞秒激光微加工和固液反应制备了由各种纳米结构覆盖的3D圆锥形微观纹理，其中3D圆锥形微观纹理的引入影响了凝聚液滴的早期分布以及随后的聚结和离开。由于凝聚液滴的生长和聚结，一些合并的液滴由于不完美的纳米级形貌或化学异质性的局部微缺陷引起的钉扎效应而无法脱离表面，从而导致产生大的钉扎液滴。 3D圆锥形微纹理的引入有助于这些钉扎液滴的离开，因为圆锥形形态的拉普拉斯排斥增强，从而抑制大液滴的增加并保持稳定的滴状冷凝。研究结果为增强超疏水表面滴状冷凝的长期鲁棒性提供了一种工程上可行的方法，从而有利于实用仿生超疏水表面的优化设计。
Achieving sustainable dropwise condensation is still a challenge for the industrial applications of bio-inspired superhydrophobic surfaces in the field of phase-change heat transfer. In this work, 3D conical microtextures covered by various nanostructures are prepared by utilizing femtosecond laser micromachining and solid-liquid reactions, where the introduction of 3D conical microtextures affected both the early distribution and the subsequent coalescence and departure of condensed droplets. Due to the growth and coalescence of condensed droplets, some merged droplets cannot depart from the surfaces due to the pinning effect caused by the localized micro-defects of imperfect nanoscale morphology or chemical heterogeneity, thus resulting in the generation of large pinned droplets. The introduction of 3D conical microtextures helps with the departure of these pinned droplets due to the enhanced Laplace expulsion of conical morphology, which inhibits the increase of large droplets and maintains stable dropwise condensation. The results provide an engineering feasible approach to enhance the long-term robustness of dropwise condensation on superhydrophobic surfaces, thus benefiting the optimal design of practical bio-inspired superhydrophobic surfaces.