Tree root-inspired robust superhydrophobic coatings with high permeation for porous structures

Guoliang Zhang; Qingyi Xie; Jinfeng Chi; Yuxian Chen; Hao Zheng; Chunfeng Ma; Guangzhao Zhang

doi:10.1016/j.isci.2021.103197

Tree root-inspired robust superhydrophobic coatings with high permeation for porous structures

iScience. 2021 Sep 30;24(10):103197. doi: 10.1016/j.isci.2021.103197. eCollection 2021 Oct 22.

Authors

Guoliang Zhang¹, Qingyi Xie¹, Jinfeng Chi¹, Yuxian Chen¹, Hao Zheng¹, Chunfeng Ma¹, Guangzhao Zhang¹

Affiliation

¹ Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou, China.

Abstract

Superhydrophobic coatings have tremendous potential for protecting porous structures from corrosion. However, the weak adhesion and poor abrasion resistance have long been challenges for their real-life applications. Inspired by tree roots, we prepared a robust superhydrophobic coating by spraying fluorinated nanodiamonds (FNDs) on a permeable epoxy coating. The epoxy can not only coat the surface but also permeate deeply inside a porous substrate and consolidate in situ as tree roots in soil. Thus, the structure is thoroughly reinforced where the pull-off strength reaches 9.4 MPa for concrete. On the other hand, the surface is covered with immobilized FNDs, forming a superhydrophobic surface. Thanks to the ultra-hard FNDs, the coating surface has high abrasion resistance and its superhydrophobicity holds even after 100 abrasion cycles. Moreover, it exhibits self-cleaning, anti-icing, and anticorrosion performance. It is promising in protecting various porous structures such as concrete, wood, and untreated corroded steel.

Keywords: Biomimetics; Nanomaterials; Surface science.