News

New surface makes oil contamination remove itself

Researchers of Aalto University have developed surfaces where oil transports itself to desired directions.

Oil drop moves away from the landing point to the direction set by geometrical patterning of the surface. Video: Ville Jokinen, Visa Noronen, Sebastian Röder.

Researchers' oleophobic surfaces are microtextured with radial arrays of undercut stripes. When oil drops fall on these surfaces, drops move away from the landing point to the direction set by asymmetric geometrical patterning of the surface. The surfaces open new avenues for power-free liquid transportation and oil contamination self-removal applications in analytical and fluidic devices.

– We developed surfaces that are able to move liquid oil droplets by surface tension forces. Droplets from anywhere within the pattern will spontaneously move to the center of the pattern, tells Postdoctoral Researcher Ville Jokinen.

- Although surface engineering facilitates effective liquid manipulation and enables water droplet self-transportation on synthetic surfaces, self-transportation of oil droplets posed a major challenge because of their low surfacetension, explains Postdoctoral Researcher Xuelin Tian.

Oil drop moves away from the landing point to the direction set by asymmetric geometrical patterning of the surface. Photo: Ville Jokinen / Aalto University

New surfaces are also able to move low surface tension liquids other than oil. They work for water, wine and even pure ethanol. Directional liquid transportation of water is also found in nature, for instance, in cactus needles and the shells of desert beetles. Researchers see a range of industrial applications.

– The droplets position themselves very accurately at the center of the pattern. This could be used to deposit arrays of functional materials. We envision the patterns being used the other way around as well, for instance, to transport unwanted stray droplets away from critical areas of devices, such as to prevent clogging of nozzles in inkjet printing, says Professor Robin Ras.

Contact details:

Postdoctoral Researcher Ville Jokinen
Aalto University (Finland)
[email protected]
Tel. +358 40 587 0425

Professor Robin Ras
Aalto University (Finland)
[email protected]
Tel. +358 50 432 6633
http://physics.aalto.fi/smw

Research article: Juan Li, Qi Hang Qin, Ali Shah, Robin H. A. Ras, Xuelin Tian, Ville Jokinen: Oil droplet self-transportation on oleophobic surfaces. Science Advances 2016. DOI 10.1126/sciadv.1600148

Link to the article (advances.sciencemag.org)

 

  • Published:
  • Updated:
Share
URL copied!

Read more news

Picture of Marika Tervahartiala and Kamyar Hasanzadeh after the event in front of the Hybrid Stage area.
Research & Art Published:

Perspectives on open data: Aalto Research Data Uncovered

Marika Tervahartiala and Kamyar Hasanzadeh took the stage to share their insights on opening geographic and visual data.
Photo of a bolometer
Press releases Published:

Quantum scientists accurately measure power levels one trillion times lower than usual

A new device can measure power levels with unprecedented accuracy and sensitivity, offering a major step forward for quantum technologies
SSD posters
Press releases Published:

The world's and Finland's biggest sustainability science events under the same roof next year

University of Helsinki and Aalto University are participating in organizing a major international conference on sustainability sciences in June 2024. The event organized in Helsinki and Espoo combines the international SRI congress and Sustainability Science Days.
Research & Art Published:

Alternatives to fossil-based fibres – Helena Sederholm develops sustainable textiles

Today’s outdoor clothing mainly relies on oil-based fibres and chemicals that are harmful for the environment. In her doctoral research, Helena Sederholm develops environmentally friendly water-repellent textiles. She follows the example of nature.