Complex Nanowrinkling in Chiral Liquid Crystal Surfaces: From Shaping Mechanisms to Geometric Statistics

Surface wrinkling is closely linked to a significant number of surface functionalities such as wetting, structural colour, tribology, frictions, biological growth and more. Given its ubiquity in nature’s surfaces and that most material formation processes are driven by self-assembly and self-organiz...

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Auteurs principaux: Ziheng Wang, Phillip Servio, Alejandro D. Rey
Format: Article
Langue:English
Publié: MDPI AG 2022-05-01
Collection:Nanomaterials
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Accès en ligne:https://www.mdpi.com/2079-4991/12/9/1555
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author Ziheng Wang
Phillip Servio
Alejandro D. Rey
author_facet Ziheng Wang
Phillip Servio
Alejandro D. Rey
author_sort Ziheng Wang
collection DOAJ
description Surface wrinkling is closely linked to a significant number of surface functionalities such as wetting, structural colour, tribology, frictions, biological growth and more. Given its ubiquity in nature’s surfaces and that most material formation processes are driven by self-assembly and self-organization and many are formed by fibrous composites or analogues of liquid crystals, in this work, we extend our previous theory and modeling work on in silico biomimicking nanowrinkling using chiral liquid crystal surface physics by including higher-order anisotropic surface tension nonlinearities. The modeling is based on a compact liquid crystal shape equation containing anisotropic capillary pressures, whose solution predicts a superposition of uniaxial, equibiaxial and biaxial egg carton surfaces with amplitudes dictated by material anchoring energy parameters and by the symmetry of the liquid crystal orientation field. The numerical solutions are validated by analytical solutions. The blending and interaction of egg carton surfaces create surface reliefs whose amplitudes depend on the highest nonlinearity and whose morphology depends on the anchoring coefficient ratio. Targeting specific wrinkling patterns is realized by selecting trajectories on an appropriate parametric space. Finally, given its importance in surface functionalities and applications, the geometric statistics of the patterns up to the fourth order are characterized and connected to the parametric anchoring energy space. We show how to minimize and/or maximize skewness and kurtosis by specific changes in the surface energy anisotropy. Taken together, this paper presents a theory and simulation platform for the design of nano-wrinkled surfaces with targeted surface roughness metrics generated by internal capillary pressures, of interest in the development of biomimetic multifunctional surfaces.
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spelling doaj.art-a9b76bbd2dba4a3aa13f1c1c28f3f13a2023-11-23T08:56:00ZengMDPI AGNanomaterials2079-49912022-05-01129155510.3390/nano12091555Complex Nanowrinkling in Chiral Liquid Crystal Surfaces: From Shaping Mechanisms to Geometric StatisticsZiheng Wang0Phillip Servio1Alejandro D. Rey2Department of Chemical Engineering, McGill University, 3610 University St., Montréal, QC H3A 0C5, CanadaDepartment of Chemical Engineering, McGill University, 3610 University St., Montréal, QC H3A 0C5, CanadaDepartment of Chemical Engineering, McGill University, 3610 University St., Montréal, QC H3A 0C5, CanadaSurface wrinkling is closely linked to a significant number of surface functionalities such as wetting, structural colour, tribology, frictions, biological growth and more. Given its ubiquity in nature’s surfaces and that most material formation processes are driven by self-assembly and self-organization and many are formed by fibrous composites or analogues of liquid crystals, in this work, we extend our previous theory and modeling work on in silico biomimicking nanowrinkling using chiral liquid crystal surface physics by including higher-order anisotropic surface tension nonlinearities. The modeling is based on a compact liquid crystal shape equation containing anisotropic capillary pressures, whose solution predicts a superposition of uniaxial, equibiaxial and biaxial egg carton surfaces with amplitudes dictated by material anchoring energy parameters and by the symmetry of the liquid crystal orientation field. The numerical solutions are validated by analytical solutions. The blending and interaction of egg carton surfaces create surface reliefs whose amplitudes depend on the highest nonlinearity and whose morphology depends on the anchoring coefficient ratio. Targeting specific wrinkling patterns is realized by selecting trajectories on an appropriate parametric space. Finally, given its importance in surface functionalities and applications, the geometric statistics of the patterns up to the fourth order are characterized and connected to the parametric anchoring energy space. We show how to minimize and/or maximize skewness and kurtosis by specific changes in the surface energy anisotropy. Taken together, this paper presents a theory and simulation platform for the design of nano-wrinkled surfaces with targeted surface roughness metrics generated by internal capillary pressures, of interest in the development of biomimetic multifunctional surfaces.https://www.mdpi.com/2079-4991/12/9/1555cholesteric liquid crystalanchoringsurface wrinklingsurface roughness
spellingShingle Ziheng Wang
Phillip Servio
Alejandro D. Rey
Complex Nanowrinkling in Chiral Liquid Crystal Surfaces: From Shaping Mechanisms to Geometric Statistics
Nanomaterials
cholesteric liquid crystal
anchoring
surface wrinkling
surface roughness
title Complex Nanowrinkling in Chiral Liquid Crystal Surfaces: From Shaping Mechanisms to Geometric Statistics
title_full Complex Nanowrinkling in Chiral Liquid Crystal Surfaces: From Shaping Mechanisms to Geometric Statistics
title_fullStr Complex Nanowrinkling in Chiral Liquid Crystal Surfaces: From Shaping Mechanisms to Geometric Statistics
title_full_unstemmed Complex Nanowrinkling in Chiral Liquid Crystal Surfaces: From Shaping Mechanisms to Geometric Statistics
title_short Complex Nanowrinkling in Chiral Liquid Crystal Surfaces: From Shaping Mechanisms to Geometric Statistics
title_sort complex nanowrinkling in chiral liquid crystal surfaces from shaping mechanisms to geometric statistics
topic cholesteric liquid crystal
anchoring
surface wrinkling
surface roughness
url https://www.mdpi.com/2079-4991/12/9/1555
work_keys_str_mv AT zihengwang complexnanowrinklinginchiralliquidcrystalsurfacesfromshapingmechanismstogeometricstatistics
AT phillipservio complexnanowrinklinginchiralliquidcrystalsurfacesfromshapingmechanismstogeometricstatistics
AT alejandrodrey complexnanowrinklinginchiralliquidcrystalsurfacesfromshapingmechanismstogeometricstatistics