Direct writing of colloidal suspensions onto inclined surfaces: optimizing dispense volume for homogeneous structures
Citation Link: https://doi.org/10.15480/882.3478
Publikationstyp
Journal Article
Date Issued
2021-03-10
Sprache
English
TORE-DOI
TORE-URI
Volume
597
Start Page
137
End Page
148
Citation
Journal of Colloid and Interface Science 597: 137-148 (2021-09-01)
Publisher DOI
Scopus ID
Publisher
Elsevier
Hypothesis: A process to fabricate structures on inclined substrates has the potential to yield novel applications for colloidal-based structures. However, for conventional techniques, besides the coffee ring effect (CRE), anisotropic particle deposition along the inclination direction (IE) is expected to occur. We hypothesize that both effects can be inhibited by reducing the dispense volume during printing by direct writing. Experiments: We combined an additive manufacturing technique, namely direct writing, with colloidal assembly (AMCA) for an automated and localized drop-cast of polystyrene and silica suspensions onto inclined surfaces. Herein, we investigated the influence of the substrate tilting angle and the dispense volume on the printing of colloids and the resulting structures’ morphology. Findings: The results demonstrate that a reduction in the dispense volume hinders the CRE and IE for both particles’ systems, even though the evaporation mode is different. For polystyrene, the droplets evaporated solely in stick-mode, enabling a “surface capturing effect”, while for silica, droplets evaporated in mixed stick–slip mode and a “confinement effect” was observed, which improved uniformity of the deposition. These findings were used to generate a model of the critical droplet radius needed to print homogeneous colloidal-based structures onto inclined substrates.
Subjects
Colloidal suspension
Confinement effect
Direct writing
Inclined surface
Photonic structure
Self-assembly
Surface capturing effect
DDC Class
600: Technik
Publication version
publishedVersion