Directed Self-Assembly of Colloidal Particles onto Nematic Liquid Crystalline Defects Engineered by Chemically Patterned Surfaces

Xiao Li, Julio C. Armas-Pérez, Juan P. Hernández-Ortiz, Christopher G. Arges, Xiaoying Liu, José A. Martínez-González, Leonidas E. Ocola, Camille Bishop, Helou Xie, Juan J. De Pablo, Paul F. Nealey

Research output: Contribution to journalArticlepeer-review

18 Scopus citations

Abstract

In exploiting topological defects of liquid crystals as the targeting sites for trapping colloidal objects, previous work has relied on topographic features with uniform anchoring to create defects, achieving limited density and spacing of particles. We report a generalizable strategy to create topological defects on chemically patterned surfaces to assemble particles in precisely defined locations with a tunable interparticle distance at nanoscale dimensions. Informed by experimental observations and numerical simulations that indicate that liquid crystals, confined between a homeotropic-anchoring surface and a surface with lithographically defined planar-anchoring stripes in a homeotropic-anchoring background, display splay-bend deformation, we successfully create pairs of defects and subsequently trap particles with controlled spacing by designing patterns of intersecting stripes aligned at 45° with homeotropic-anchoring gaps at the intersections. Application of electric fields allows for dynamic control of trapped particles. The tunability, responsiveness, and adaptability of this platform provide the opportunities for assembly of colloidal structures toward functional materials.

Original languageEnglish (US)
Pages (from-to)6492-6501
Number of pages10
JournalACS nano
Volume11
Issue number6
DOIs
StatePublished - Jun 27 2017

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

Cite this