Published in

Royal Society of Chemistry, Journal of Materials Chemistry A: materials for energy and sustainability, 43(2), p. 18531-18538

DOI: 10.1039/c4ta04090b

Links

Tools

Export citation

Search in Google Scholar

Controllable wettability and adhesion on bioinspired multifunctional TiO2 nanostructure surfaces for liquid manipulation

This paper is available in a repository.
This paper is available in a repository.

Full text: Download

Green circle
Preprint: archiving allowed
Orange circle
Postprint: archiving restricted
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

Hierarchical surfaces with specific topographical morphology and chemical component can be found on many living creatures in nature. They offer special wettability and adhesion (sliding, sticky or patterned superhydrophobic surfaces) a functional platform for microfluidic management and other biological functions. Inspired by their precise arrangement of structures and surface components, we described a facile electrochemical technique to large scale create a dual-scale hierarchical anatase TiO2 structures with the combination of pinecone-like micro-particle upper layer and dense-stacked nanoparticle bottom layer. The as-prepared TiO2 films display excellent superhydrophilic property in air, change to underwater superoleophobicity with good dynamical stability. Extremely high contrast of adhesion (2.5-170 µN) can be realized by adjusting the physical structures (anodizing voltage and electrolyte concentration dependent) to control the solid-liquid contact state (from “Rose” to “Lotus” state). In addition, by taking advantage of the excellent photocatalytic activity of anatase TiO2, erasable and rewritable patterned superhydrophobic TiO2 films were constructed for a versatile platform for microfluidic management. In a proof-of-concept study, robust super-antiwetting films for on-demand droplet separation, mixing and transportation under ambient atmosphere or underwater environment, and patterned superhydrophobic surfaces for liquid self-assembling or anti-counterfeiting mark were demonstrated.