Synthesis of Boron Nitride Nanotube on Substrates and Its Superhydrophobicity

Friday, November 20, 2009 3:30 – 3:50 pm
Room 610, M&M Building

Chee Huei Lee
Graduate Student
Department of Physics
Michigan Technological University

Abstract

Boron nitride nanotubes (BNNTs) are wide bandgap semiconductors (theoretical value of ~5.5eV), in which the bandgap is insensitive to the number of walls, diameters as well as chiralities.They are potential useful in deep-UV optoelectronic devices, high temperature electronic,nanocomposites, clinical boron neutron capture therapy, and so on. However, the synthesis of BNNTs is challenging, compared to that of carbon nanotubes (CNTs).The chemistry of the process is more involved and usually requires high temperature. We showthat effective growth of high quality BNNTs can be obtained in our lab by a simple thermalchemical vapor deposition technique (Thermal-CVD) at 1200°C, with growth vapor trappingapproach. Furthermore, it is found that the BNNT films can achieve superhydrophobic state with the watercontact angle exceeding 150 degree. Some experiment results will be presented during theseminar. Since BNNTs are chemically inert and resistive to oxidation up to 1000°C, itssuperhydrophobic behavior could be potentially useful as self-cleaning, insulating andanticorrosive coating under rigorous chemical and thermal conditions.

Aging-Stabilization of Ferroelectric Domains due to ShortRange Ordering of Charged Point Defects

Friday, November 20, 2009 3:05 – 3:25 pm
Room 610, M&M Building

Tianle Cheng
Graduate Student
Department of Materials Science and Engineering
Michigan Technological University

Abstract

Phase field simulation, thermodynamic analysis and ionic interaction analysis arerespectively conducted to study the aging-stabilization effect in dopedferroelectrics. Phase field model takes into account various energetic contributionsinvolved in domain aging phenomenon, including chemical, domain wall,electrostatic and elastostatic energies, as well as internal bias electric fieldassociated with the short-range ordering of charged point defects. The internalelectric field strength is estimated by computer simulation. Clausius-Clapeyrontype thermo- dynamic analysis of field-induced ferroelectric phase transition isused to evaluate aging-associated internal electric field magnitude from availableexperimental data, which is in agreement with the computer simulation. Fromatomic level, ionic interaction analysis on charged point defect configurationsshows that defect dipole-dipole interaction may play important role in theferroelectric aging phenomenon.

National Science Foundation Awards Nearly $4.2 Million for Research at Michigan Tech

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Eight research projects in eight different fields at Michigan Technological University are receiving grants totaling $4,172,719 from the National Science Foundation (NSF). Funding for four of the projects comes from the American Reinvestment and Recovery Act of 2009 (ARRA), also known as federal stimulus money. The newly funded research includes using metal organic frameworks for potentially cost-effective hydrogen storage and bringing the technology of hydrogen-based energy into high school classrooms, Principal investigator: Yun Hang Hu, Materials Science and Engineering and Institute of Materials Processing, $302,650.

Materials and Life Science Investigations in Atomic Force Microscopy

Friday, November 13, 2009 3:00 – 4:00 pm
Room 610, M&M Building

Adam Mednick
Veeco Instruments
Santa Barbara, CA

Abstract

Atomic Force Microscopy (AFM) is a versatile technique due to its ability to characterizematerials ranging from biopolymers to semiconductor surfaces.  Besides the ability to studysurfaces at the nanometer scale, AFM can be used to study materials properties of the samplesby related techniques that make up the field of Scanning Probe Microscopy (SPM).  There areseveral techniques for electrical characterization to study electrostatic fields, current flow, andpiezoelectric behavior of the materials.  Properties such as elastic modulus, adhesion, andenergy dissipation can be studied by conducting force measurements during TappingModeimaging using the harmonic oscillation behavior of the cantilever, forming a new techniquecalled HarmoniX.  AFM technology is also commonly used to manipulation features at thenanometer scale.  Life science applications consist of studying macromolecules up to live cells.Cellular studies often consist of integrating the AFM with fluorescence and confocal microscopywhich can be integrated with the system to direct the AFM data collection.  This presentation willprovide an overview of these and other applications of AFM to provide a view of how thetechnique is used currently, and where it is progressing in the future.

Biography

Adam Mednick is a Veeco Applications Engineer, based in Santa Barbara, CA.Adam has spent the last 3 years in the AFM applications group, where he has played asignificant role in developing the Dimension ICON, Veeco’s new flagship research AFMplatform.  He has a broad range of practical experience with various measurements that arepossible with AFM, especially material and electrical characterization techniques.  Prior tojoining Veeco, Adam performed his graduate research at Lawrence Livermore National Lab inthe Center for Micro and Nano Technologies.  He received his M.S. in Electrical Engineeringand B.S. in Physics and Electrical Engineering from Cal Poly, San Luis Obispo, and his MBAfrom Pepperdine University’s Graziadio School of Business.

Real-Time Electro-Mechanical Coupling in One-Dimensional Materials

Friday, November 6, 2009 3:00 – 4:00 pm
Room 610, M&M Building

Prof. Reza Shahbazian-Yassar
Department of Mechanical Engineering Engineering Mechanics
Michigan Technological University

Abstract

Nanomaterials including nanotubes and nanowires are the smallest buildingblocks for future small-scale electronics, and energy conversion technologies.Therefore it is very important to understand the intrinsic physical and mechanicalproperties of these low-dimensional nanostructures. At Michigan Tech, through arecent NSF-MRI grant we have gained access to an advanced characterizationtechnique that enables simultaneous electrical, mechanical, and structuralmonitoring of nano-scale materials. This talk gives an overview on some of thecurrent research of the PI on organic and inorganic nanowires and nanotubesused for solar cells, nanogenerators, nanoelectronics, and high-strengthbiocomposites.

Biography

Dr. Reza Shahbazian-Yassar received his PhD from Washington State University in2005. He is currently an assistant professor and adjunct assistant professor at the departmentsof Mechanical Engineering-Engineering Mechanics and Materials Science and Engineering atMichigan Tech. He joined Michigan Tech in fall 2007. Prior to his position at Tech, he was apost-doctorate research associate at the Multiscale Modeling group of Prof. Mark Horstemeyerat Mississippi State University. Dr. Yassar’s research is being supported through NSF, DOE,Michigan Space Grant Consortium, Michigan Tech Research Excellence Fund, and MuSTI.