Surface Tensions of Picoliter Droplets with Sub-Millisecond Surface Age

Rachael E.H. Miles, Michael W.J. Glerum, Hallie C. Boyer, Jim S. Walker, Cari S Dutcher, Bryan R. Bzdek

Research output: Contribution to journalArticlepeer-review

22 Scopus citations

Abstract

Aerosols are key components of the atmosphere and play important roles in many industrial processes. Because aerosol particles have high surface-to-volume ratios, their surface properties are especially important. However, direct measurement of the surface properties of aerosol particles is challenging. In this work, we describe an approach to measure the surface tension of picoliter volume droplets with surface age <1 ms by resolving their dynamic oscillations in shape immediately after ejection from a microdroplet dispenser. Droplet shape oscillations are monitored by highly time-resolved (500 ns) stroboscopic imaging, and droplet surface tension is accurately retrieved across a wide range of droplet sizes (10-25 μm radius) and surface ages (down to ∼100 μs). The approach is validated for droplets containing sodium chloride, glutaric acid, and water, which all show no variation in surface tension with surface age. Experimental results from the microdroplet dispenser approach are compared to complementary surface tension measurements of 5-10 μm radius droplets with aged surfaces using a holographic optical tweezers approach and predictions of surface tension using a statistical thermodynamic model. These approaches combined will allow investigation of droplet surface tension across a wide range of droplet sizes, compositions, and surface ages.

Original languageEnglish (US)
Pages (from-to)3021-3029
Number of pages9
JournalJournal of Physical Chemistry A
Volume123
Issue number13
DOIs
StatePublished - Apr 4 2019

Bibliographical note

Publisher Copyright:
© 2019 American Chemical Society.

MRSEC Support

  • Shared

PubMed: MeSH publication types

  • Journal Article

Fingerprint

Dive into the research topics of 'Surface Tensions of Picoliter Droplets with Sub-Millisecond Surface Age'. Together they form a unique fingerprint.

Cite this