Exploring pulse-voltage-triggered optically induced electrohydrodynamic instability for femtolitre droplet generation

Feifei Wang; Fei Fei; Lianqing Liu; Haibo Yu; Peng Yu; Yuechao Wang; Gwo-Bin Lee; Wen Jung Li

doi:10.1063/1.4885549

Author(s)

Feifei Wang
Fei Fei
Lianqing Liu
Haibo Yu
Peng Yu
Yuechao Wang
Gwo-Bin Lee

Detail(s)

Original language	English
Article number	264103
Journal / Publication	Applied Physics Letters
Volume	104
Issue number	26
Publication status	Published - 2014

Link(s)

DOI	DOI https://doi.org/10.1063/1.4885549 Final Published version
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Attachment(s)	Documents 5418064.pdf Final Published version, 3.55 MB, PDF Publisher's Copyright Statement This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Feifei Wang, Fei Fei, Lianqing Liu, Haibo Yu, Peng Yu, Yuechao Wang, Gwo-Bin Lee, and Wen Jung Li , "Exploring pulse-voltage-triggered optically induced electrohydrodynamic instability for femtolitre droplet generation", Appl. Phys. Lett. 104, 264103 (2014) and may be found at https://doi.org/10.1063/1.4885549.
Link to Scopus	https://www.scopus.com/record/display.uri?eid=2-s2.0-84905662197&origin=recordpage
Permanent Link	https://scholars.cityu.edu.hk/en/publications/publication(841101f5-949f-4015-9c9c-061a82034152).html

Abstract

We present a multipoint "virtual dispenser" to draw femtolitre droplets from a dielectric fluidic thin film using pulse-voltage-triggered optically induced electrohydrodynamic instability (PVT-OEHI). The "virtual dispenser" generates instability nucleation sites by controlling the optically induced lateral electrical stress and thermocapillary flow inside an optoelectronics chip. A time scale analysis shows that the electrohydrodynamic (EHD) instability phenomenon is present; however, its external manifestation is suppressed by OEHI. We observed two droplet dispensing mechanisms which correspond to different EHD states: Taylor cone formation and optically induced EHD jet. The EHD states transition could be realized by adjusting the pulse voltage parameters to alter the morphology of dispensed micron-scale polymer droplets, which could then be formed into organized arrays of microlenses with controllable diameter and curvature based on surface tension effect. © 2014 AIP Publishing LLC.