Colloidal Pixel‐Based Micropatterning Using Uniform Janus Microparticles with Tunable Anisotropic Particle Geometry. (27th November 2018)

• Record Type: Journal Article
• Authors: Han, Sang Woo; Choi, Song‐Ee; Chang, Douglas H.; Lee, Duho; Kim, Bohyun; Yang, Hakyeong; Seo, Minjeong; Kim, Jin Woong
• Is Part Of: Advanced functional materials. Volume 29:Number 6(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-11-27
• Subjects: 2D colloidal arrays -- anisotropic geometry -- colloidal micropatterning -- Janus microparticles -- steric constraints; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201805392
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: A new platform for designing 2D colloidal arrays by using Janus microparticles (JMPs) with tunable anisotropic particle geometry is introduced. The JMPs are synthesized by the photopolymerization of biphasic emulsion droplets produced by capillary‐based microfluidics while adjusting the spreading coefficient between −4.4 and −7.2 mN m −1 . The unidirectional rubbing of JMPs leads to their exact positioning in the stencil holes. The ratio of the hole diameter to the bigger bulb diameter of JMPs, ranging from 1.05–1.16, is critical for maximizing the positioning rate. When the anisotropic geometry factor is near zero, a standing particle configuration with a protrusion in the stencil hole is obtained more efficiently due mainly to the enhanced steric constraint. Finally, it is demonstrated that different types of JMPs with controlled sizes and geometries can be arrayed at specific hole sites of the stencil, thus enabling development of a colloidal pixel‐based micropatterning technology. Abstract : A new 2D colloidal array platform is proposed. The steric constraint of Janus microparticles (JMPs) plays a crucial role in achieving high accuracy in particle positioning on a hole‐patterned stencil. Finally, the JMPs with controlled sizes and geometries can be arrayed at specific hole sites of the stencil, thus enabling colloidal pixel‐based micropatterning.