A Confined-Etching Strategy for Intrinsic Anisotropic Surface Wetting Patterning

Natural patterns, always, have the power to catch eye and intrigue mind. Patterned surfaces with anisotropic wettability are of great interest in fundamental and industrial applications. However, surface patterning relies heavily on high-end apparatuses and expensive moulds/masks and photoresists.
Published in Materials
A Confined-Etching Strategy for Intrinsic Anisotropic Surface Wetting Patterning
Like

  Decomposition behaviors of polymers have been widely studied in material science, but as-created chemical and physical structural changes have been rarely considered as an opportunity for wettability manipulation.

Fig. 1 Fabrication strategy of accurate patterns with anisotropic wettability. a Painting ink on microporous cellulose triacetate film to temporarily construct anisotropic water penetration ability. b Confined surface etching upon the treatment with aqueous NaOH solutions. c Washing the patterned surface to remove excess NaOH and drying for permanent patterns.

  In our recent work, we report a facile and fast mask-free etching method for accurate surface patterning by controlling the confined decomposition of material surfaces. With a common printing technology, intrinsic, complex and accurate patterns (QR code, for example) are fabricated efficiently. Such intrinsic patterns can be used for realizing information storage and encryption. With selective wettability, pattern information can be stored and encrypted on the cellulose film; upon exposure to external stimuli, such as water, encryption keys can be read. Moreover, such a method can also be used to prepare functional materials, flexible electronics for instance. The as-prepared Ag electrode presents high electrical conductivity (63.9×106 S cm-1) and bending-deformation resistance. 

Fig. 1 Information storage and encryption. Preparation (a) and rapid water-response (b) of the hidden pattern “SCU FBR”. c Reversible decryption of the hidden information by water mist. d A QR code ink-printed on HC film before NaOH-treatment and the reading process of the hidden QR code after NaOH-treatment.

Fig. 6 Fabrication of flexible electronics. a Digital image of the patterned EHC. b Digital and SEM images of Ag electrodes. c Photograph of the bent Ag electrodes. d EDS spectra of the Ag electrode (inserted are element mapping images). e Cross-section SEM image of the Ag electrode and corresponding element mapping image. f Photograph of a conductive loop equipped with the Ag electrode.

Such surface wettable patterning strategy is scalable, as long as ay substrates satisfy the three requirements:

1) chemical reactions/treatments (including chemical degradation, decomposition, and even conjugation) can be conducted for substrate surfaces;

2) the substrate surfaces can be written with inks and can well maintain ink patterns;

3) the original region and ink-printed region have different wettabilities to etching agents, enabling confined-etching treatments.

Such a mask-free and simple method shows great potential in the mass production of accurate functional patterns. We believe this strategy can be applied for more material surfaces, bringing more opportunities for wide applications.

For more details, see our paper in Nature Communications: 

https://doi.org/10.1038/s41467-022-30832-4

Please sign in or register for FREE

If you are a registered user on Research Communities by Springer Nature, please sign in

Subscribe to the Topic

Materials Science
Physical Sciences > Materials Science

Related Collections

With collections, you can get published faster and increase your visibility.

Applied Sciences

This collection highlights research and commentary in applied science. The range of topics is large, spanning all scientific disciplines, with the unifying factor being the goal to turn scientific knowledge into positive benefits for society.

Publishing Model: Open Access

Deadline: Ongoing