Friday, February 26, 2010 3:00 – 4:00 pm
Room 610, M&M Building
Dr. Dennis Desheng Meng
Multi-Scale Energy System (MuSES) Laboratory
Department of Mechanical Engineering – Engineering Mechanics
Michigan Technological University
Microfluidic technology has inspired significant scientific interest and shown promising applications in health care,energy, and national security. Manipulation of surface tension and wettability is regard as a core technology ofmicrofluidics. The unique interfacial phenomena at microscale both formed a foundation of this emerging researchfield and offered many powerful tools to implement microfluidic devices. This seminar will discuss the followingthree examples:
- Self-regulated microfluidic management for microfuel cells are achieved by hydrophobic venting andbubble-driven micropumping, which are based on nanoporous membrane and microchannels with designedwetting/nonwetting patterns respectively. An embedded self-pumping mechanism is demonstrated to deliverthe liquid fuel of micro direct methanol fuel cells (μDMFCs) by employing the CO2 gas bubbles generated bythe fuel cell reactions without any power consumption. On-demand gas generators are also developed tosupply hydrogen and oxygen to a micro polymer electrolyte membrane (PEM) fuel cell, which is automaticallyregulated according to the need of the fuel cell current output.
- Superhydrophilic surfaces are obtained and tested to investigate their antifogging, antifoulingproperties for microfluidic devices. After hydrophilic treatments, both polyester film and ITO glassdemonstrated reduced adhesion with florescent particles. The superhydrophilicity and its degradation areattributed to the surface functional groups.
- Self-assembly of bubble/droplet arrays is introduced as a promising microfabrication method. Theaffinity of bubbles/droplets to surfaces in liquid environments is quantified by bubble capturing potential “Fbc”.Self-assembly of low melting-point alloy droplets is employed to fabricate self-adaptive thermal switch array forthermal management of micro power sources.The presentation will also give brief introductions on other on-going projects in the speaker’s group (MuSES lab),including high voltage electrophoretic deposition of nanoforests and microfluidic fabrication of self-healingmaterials.
Dennis Desheng Meng is currently an Assistant Professor at the Department of MechanicalEngineering – Engineering Mechanics of Michigan Tech. He obtained his Ph.D. degree in Mechanical Engineeringfrom the University of California at Los Angeles (UCLA) in 2005 along with the Outstanding Ph.D. Award. After hejoined Michigan Tech in August 2007, Dr. Meng started the Multi-Scale Energy Systems (MuSES) Laboratory towork on micro- and nanotechnology for energy applications. The research of MuSES lab is based upon micro- andnanofabrication, such as novel electrochemical methods, microfluidic fabrication and surface treatment. Particularattentions are given to the design and fabrication of micro power sources, such as micro fuel cells, micro batteries,micro supercapacitors, as well as their thermal management.