Mechanical Engineering Seminar
Title: |
New Frontiers in Electrokinetics |
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Speaker: |
Dr. Cullen R. Buie |
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Affiliation: |
Department of Mechanical Engineering, MIT, Cambridge |
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When: |
Thursday, October 28, 2010 at 3:00:00 PM |
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Where: |
MRDC Building, Room 4211 |
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Host: |
Dr. Al Ferri | |
Abstract Electrokinetics is the transport of particles and liquids in response to an applied electric field. The two most common electrokinetic phenomena are electroosmosis (bulk liquid flow in response to a DC field) and electrophoresis (particle transport in response to DC field). Both phenomena favor small length scales (1-10 microns) and thus have found several applications in microfluidics. However, in this talk we explore two new applications for electrokinetic phenomena outside the realm of 'lab on a chip'. First, we discuss how electroosmotic (EO) pumps can enhance power output from proton exchange membrane fuel cells (PEMFCs). PEMFCs are attractive energy conversion devices for transportation and portable electronics applications. However, they are currently limited by the parasitic power associated with auxiliary pumping systems. In this talk we show that EO pumps can be used to manage liquid reactants and products in PEMFCs while significantly increasing their power output. Second, we have demonstrated that electrophoretic deposition (EPD) can be used to create superhydrophobic surfaces. Superhydrophobic surfaces are defined by contact angles greater than 150 degrees and roll off angles less than 10 degrees. These surfaces are attractive for many applications including heat exchangers, anti-biofouling surfaces, and self-cleaning surfaces. But, despite their potential, superhydrophobic surfaces have found few true commercial applications due to materials and processing costs. Here we show that using EPD of commercial nanoparticles we can achieve contact angles exceeding 160 degrees after only one minute of deposition. We believe that EPD offers an inexpensive method to engineer low surface energy materials and bring superhydrophobic surfaces closer to market. |
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Biography Cullen Buie is the Mitsui Career Development Chair and Assistant Professor of Mechanical Engineering at MIT. He obtained his Ph.D. in Mechanical Engineering from Stanford University in 2009. Prior to joining MIT Cullen spent a year at UC Berkeley working with Professor Liwei Lin and Professor John Coates as a UC President’s Postdoctoral Fellow. At MIT his laboratory explores applications of electrokinetics in materials science, energy, and microbiology |
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