Resolving the Apparent Line Tension of Sessile Droplets and Understanding its Sign Change at a Critical Wetting Angle

Zhao, Binyu; Luo, Shuang; Bonaccurso, Elmar; Auernhammer, Guenter K.; Deng, Xu; Li, Zhigang; Chen, Longquan

doi:10.1103/physrevlett.123.094501

Cited by 27 publications

(16 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…39,42 One may need further interpretations on its origins such as surface heterogeneities or thermodynamic properties. 43,44 Another interesting finding is that most of the nanodroplets, especially the larger ones were located in the center area surrounded by four circular holes instead of the area between two nearest holes. This phenomenon can be interpreted as such an area provides more free space for the growth of nanodroplets in two dimensions, in contrast to the onedimensional confinement of NT arrays.…”

Section: ■ Results and Discussionmentioning

confidence: 98%

See 1 more Smart Citation

Wetting Behavior of Surface Nanodroplets Regulated by Periodic Nanostructured Surfaces

Zhou

Yang

Quan

et al. 2021

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

Surfaces with nanostructure patterning are broadly encountered in nature, and they play a significant role in regulating various phenomena such as phase transition at the liquid/solid interface. Here, we designed two kinds of template substrates with periodic nanostructure patterns [i.e., nanotrench (NT) and nanopore (NP)]. Surface nanodroplets produced on these nanostructure surfaces were characterized to acquire their morphology and wetting properties. We show that nanostructure patterning could effectively regulate the shape, contact radius, and nucleate site of nanodroplets. While nanodroplets on the NT structure are constrained in one dimension, nanodroplets on the NP structure have enhanced the wetting property with constraints from two dimensions. Further numerical analysis indicates that the morphology and contact angles of nanodroplets on the NT structure depend on the substrate wettability and the droplet volume. These observations demonstrate how physical geometry and chemical heterogeneity of a substrate surface affect the growth and spreading of surface nanodroplets, which deepens our understanding on nanoscale phase separation.

show abstract

Section: ■ Results and Discussionmentioning

confidence: 98%

“…Another reason may come from the nonlinearity of cos θ versus 1/ r . It was argued that the modified Young–Dupre’s equation or line tension alone is insufficient to describe the wetting behavior at the microscopic level. , One may need further interpretations on its origins such as surface heterogeneities or thermodynamic properties. , …”

Section: Resultsmentioning

confidence: 99%

Wetting Behavior of Surface Nanodroplets Regulated by Periodic Nanostructured Surfaces

Zhou

Yang

Quan

et al. 2021

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

show abstract

“…From a thermodynamical viewpoint, the line tension can be positive or negative while preserving the coexistence of the adjacent phases (4). Nevertheless, in the particular case of solid/liquid/vapor triple lines, recent works indicate that a negative sign is mainly expected apart for a system close from the wetting transition (9,10). For instance, for ordered hydrophobic nanopores of a few nm in diameter, it has been shown experimentally and confirmed numerically that large drying pressures of more than 200 bars are induced by a negative line tension.…”

mentioning

confidence: 99%

Carbon dioxide as a line active agent: Its impact on line tension and nucleation rate

Bey

Coasne

Picard

2021

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

By considering a water capillary bridge confined between two flat surfaces, we investigate the thermodynamics of the triple line delimiting this solid–liquid–vapor system when supplemented in carbon dioxide. In more detail, by means of atom-scale simulations, we show that carbon dioxide accumulates at the solid walls and, preferably, at the triple lines where it plays the role of a line active agent. The line tension of the triple line, which is quantitatively assessed using an original mechanical route, is shown to be driven by the line excess concentrations of the solute (carbon dioxide) and solvent (water). Solute accumulation at the lines decreases the negative line tension (i.e., more negative) while solvent depletion from the lines has the opposite effect. Such an unprecedented quantitative assessment of gas-induced line tension modifications shows that the absolute value of the negative line tension increases upon increasing the carbon dioxide partial pressure. As a striking example, for hydrophilic surfaces, the line tension is found to increase by more than an order of magnitude when the carbon dioxide pressure exceeds 3 MPa. By considering the coupling between line and surface effects induced by gaseous adsorption, we hypothesize from the observed gas concentration-dependent line tension a nontrivial impact on heterogeneous nucleation of nanometric critical nuclei.

show abstract

“…We prepared nanodroplets , with r ≈ 50–350 nm by heating the ionic liquid 1-decyl-3-methylimidazolium tetra-fluoroborate (γ = 29.5 mN/m) to evaporate and then condensing it on different cross-linked polydimethylsiloxane (PDMS) substrates (∼2 mm in thickness and G = 31–550 kPa). These cross-linked PDMS substrates were pretreated to have the free oligomers been extracted .…”

mentioning

confidence: 99%

Elasticity-to-Capillarity Transition in Soft Substrate Deformation

et al. 2021

Self Cite

View full text Add to dashboard Cite

Whereas capillarity controls fluid dynamics at submillimeter scale and elasticity determines the mechanics of rigid solids, their coupling governs elastocapillary deformations on soft solids. Here, we directly probed the deformations on soft substrates induced by sessile nanodroplets. The wetting ridge created around the contact line and the dimple formed underneath the nanodroplet were imaged with a high spatial resolution using atomic force microscopy. The ridge height nonmonotonically depends on the substrate stiffness, and the dimple depth nonlinearly depends on the droplet size. The capillarity of the substrate overcomes the elasticity of the substrate in dominating the deformations when the elastocapillary length is approximately larger than the droplet contact radius, showing an experimental observation of the elasticity-to-capillarity transition. This study provides an experimental approach to investigate nanoscale elastocapillarity, and the insights have the potential to kick-off future work on the fundamentals of solid mechanics.

show abstract

Resolving the Apparent Line Tension of Sessile Droplets and Understanding its Sign Change at a Critical Wetting Angle

Cited by 27 publications

References 50 publications

Wetting Behavior of Surface Nanodroplets Regulated by Periodic Nanostructured Surfaces

Wetting Behavior of Surface Nanodroplets Regulated by Periodic Nanostructured Surfaces

Carbon dioxide as a line active agent: Its impact on line tension and nucleation rate

Elasticity-to-Capillarity Transition in Soft Substrate Deformation

Contact Info

Product

Resources

About