Tuning the Superhydrophobic Properties of Hierarchical Nano-microstructural Silica Biomorph Arrays Grown at Triphasic Interfaces

Abstract

The three-dimensional hierarchical morphology of surfaces greatly affects the wettability, absorption and microfabrication properties of their hybrid materials, however few scalable methods exist that controls simultaneously complex geometric shape and spatial scattered location and their physical properties tuned. Consequently, this report describes a synthetic strategy that enables the position of well-ordered biomorph nano-microstructures on hydrophobic surfaces to be precisely controlled. The hierarchical architecture can be accurately positioned on polydimethylsiloxane (PDMS) surfaces in an unprecedented level by leveraging a solid/liquid/gas triphase dynamic reaction diffusion system strategy. The effect of salt concentrations, pH, CO2 levels, temperature and substrate patterning on this self-assembly process has been investigated, enabling protocols to be devised that enables the hydrophobic properties of the hierarchically assembled multiscale microstructures to be tuned as required. This combined top-down/bottom-up approach can be used to produce composites with outstanding hydrophobicity properties, affording superhydrophobic materials that are capable of retaining water droplets on their surfaces, even when the material is inverted by 180°, with a wide range of potential applications in oil/water separation technology and for selective cell recognition in biological systems.

De Novo Design of Functional Coassembling Organic–Inorganic Hydrogels for Hierarchical Mineralization and Neovascularization

“…Other approaches using complementary streptavidin/biotin or antibody/antigen have been harnessed to integrate multiple inorganics in a single organic–inorganic nanocomposite . In contrast, systems based on reaction-diffusion mechanisms enable assembly of inorganics into nano-objects with spatiotemporal orientation, not readily accessible by equilibrium processes. , Examples have been demonstrated in biomineralization, microfabrication, − formation of microlenses, and dynamic materials . Reactions of inorganic species, coupled with diffusion in hydrogel media, can lead to the formation of nano-objects with structural hierarchy and complexity as well as multifunctional properties.…”