posted on 2019-07-03, 11:41authored byMeirong Song, Duan Hu, Xianfu Zheng, Lixia Wang, Zhilun Yu, Wankai An, Risong Na, Chuxin Li, Ning Li, Zhouhui Lu, Zhichao Dong, Yilin Wang, Lei Jiang
Droplet
deposition on superhydrophobic surfaces has been a great challenge
owing to the shortness of the impact contact time. Despite recent
research progress regarding flat superhydrophobic surfaces, improving
deposition on ubiquitous wired and curved superhydrophobic leaves
remains challenging as their surface structures promote asymmetric
impacts, thereby shortening the contact times and increasing the likelihood
of droplet splitting. Here, we propose a strategy to solve the deposition
problems based on an analysis of the impact dynamics and a rational
selection of additives. Combining the prominent extension property
of flexible polymers with surface tension reduction of the surfactant,
the well-chosen binary additives cooperatively solve retention and
coverage problems by limiting the fragment and enhancing local pinning
and wetting processes at a very low usage. This work advances the
understanding of droplet deposition by rationally selecting additives
based on the impact dynamics, which is believed to be useful in a
variety of spraying, coating, and printing applications.