Bioinspired and Post-Functionalized 3D-Printed Surfaces with Parahydrophobic Properties

Abstract

Desertification is a growing risk for humanity. Studies show that water access will be the leading cause of massive migration in the future. For this reason, significant research efforts are devoted to identifying new sources of water. Among this work, one of the more interesting strategies takes advantage of atmospheric non-liquid water using water harvesting. Various strategies exist to harvest water, but many suffer from low yield. In this work, we take inspiration from a Mexican plant (Echeveria pulvinate) to prepare a material suitable for future water harvesting applications. Observation of E. pulvinate reveals that parahydrophobic properties are favorable for water harvesting. To mimic these properties, we leveraged a combination of 3D printing and post-functionalization to control surface wettability and obtain parahydrophobic properties. The prepared surfaces were investigated using IR and SEM. The surface roughness and wettability were also investigated to completely describe the elaborated surfaces and strongly hydrophobic surfaces with parahydrophobic properties are reported. This new approach offers a powerful platform to develop parahydrophobic features with desired three-dimensional shape.

Inspired by the Nature: A Post-printed Strategy to Efficiently Elaborate Parahydrophobic Surfaces

“…Additionally, the aggressive conditions used to convert Cu to Cu(OH) 2 may degrade PLA (saponification), particularly at the edge of the blades or meshes. The partial saponification of PLA during oxidation has already been reported in the literature and can be confirmed by simple IR observation ( Figure S1 ) [ 44 ]. For the same surface design, the differences in roughness depending on the functionalization may be significant, but it remains in the same range for most of the cases (all numerical data presented as supplementary data).…”

“…These observations on functionalized confirmed the roughness measurements and showed that the functionalized surfaces present thin nano-crystallization as described for such kind of functionalization in the literature [ 44 , 45 , 46 ]. Most of the prepared surfaces exhibit strong hydrophobicity, with contact angles greater than what has been reported for a simple plate functionalized with a similar procedure [ 44 ]. This is particularly evident for GVB and PVB modified with long linear carboxylic acids (C6 to C18).…”

“…It is well reported in the literature that copper can be used for post-functionalization for various applications including the control of surface wettability [ 6 , 40 , 42 , 43 ]. In our group, we recently demonstrated that this approach was suitable for post-printing functionalization of surfaces [ 44 ].…”

“…In a previous work, we characterized roughness on post-printed, functionalized plates [ 44 ]. On a plate, the majority of observed roughness resulted from the printing resolution.…”

Microstructure and Hydrophobicity of the External Surface of a Sonoran Desert Beetle

“…This is particularly true in desert or semidesert regions where water is scarce and plants and animals need to optimize water-capture and -retention strategies. One can take inspiration from plants or animals to prepare surfaces suitable for water harvesting applications [ 1 , 2 ].…”