Participating Faculty and Summer Research Project Descriptions
Professor Mark Brongersma
“Synthesis and Optical Characterization of Silicon Nanowires”
In this summer project, an undergraduate will learn to grow silicon nanowires using a new laser-assisted growth technique. Scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy will be used to characterize the nanowires. These studies will lead to the development of nanowire-based light sources on a Si chip.
Professor Bruce Clemens
“Nanoparticle Phase Stability”
The goal of this summer project is to examine the phase stability in nanostructured materials, where the influence of interfaces can result in behavior that is drastically different from the bulk. The student will grow nanoparticles by a variety of versatile vapor phase techniques and examine their structure as a function of particle size and alloy composition. This program will provide excellent training and educational experience for the undergraduate researcher by providing a multi–faceted research environment, including experience in synthesis, vacuum deposition, and nanophase characterization.
Professor Yi Cui
“Nanocrystal and Nanowire Synthesis, Characterization and Devices”
This project develops novel nanowire and nanocrystal materials toward nanoscale electronics and energy conversion devices. Students will have an opportunity to learn about nanocrystal and nanowire synthesis, structure characterization, single nanostructure measurement, surface modification, self-assembly, device fabrication and testing. The exciting tools include scanning electron microscopy, transmission electron microscopy, X-ray diffraction, electron beam lithography, probe station and Langmuir-Blodgett.
Professor Reinhold Dauskardt
“Adhesion in Thin-Film Structures Containing Nanostructured Materials”
The intent of this project is to study the nano-mechanical properties and adhesion of advanced thin-film structures that have applications in a wide range of emerging technologies. The goal of the work is to develop a fundamental understanding of how the films’ mechanical properties are related to their nanostructure and processing conditions. In particular, we will be interested in how the films are affected by the presence of selected solution chemistries that may be associated with processing or operating conditions. The student will gain familiarity and experience with a number of experimental techniques, including thin-film sample preparation and adhesion testing, and the use of atomic force microscopy, X-ray photoelectron spectroscopy, and possibly scanning electron microscopy for analyzing fracture surface composition and morphology.
Professor Sarah Heilshorn
“Biomaterials for Cardiovascular Engineering”
Recently, it has been discovered that biomechanics can play a large role in directing stem cell differentiation into cardiomyocytes (heart muscle cells). However, very few biocompatible materials are available that have tunable mechanical properties. Therefore, we have designed a family of protein-polymer scaffolds that both promote cell adhesion and exhibit a range of mechanical properties. The goal of this summer project will be i) to optimize the synthesis and purification of the scaffold materials and ii) to analyze the nano-topography of the material using electron microscopy in order to determine which scaffolds are ideally suited for stem cell experiments.
“Biotemplates to Create Conducting Nanoscale Structures”
Nature has evolved ways to assemble complex nanostructures with amazing precision. We aim to borrow the techniques that Nature has evolved in order to create nanoscale structures that may be useful in solar cells or micro-batteries. The specific goals of this summer project will be i) to optimize the purification of the self-assembling protein from biological tissue and ii) to analyze the nano-topography of the material using electron microscopy.
Professor Aaron Lindenberg
“Ultrafast THz Control and Characterization of Nanoscale Materials”
Intense, near half-cycle pulses of light in the far-infrared will be used to both probe and control ultrafast carrier transport phenomena in nanoscale materials. The project will also involve investigation of nanoscale THz emitters as a basis for performing THz microscopy with femtosecond resolution.
Professor Michael McGehee
“Improving the Properties of Semiconducting Polymers for Photovoltaic Cells”
We are making a new type of low cost photovoltaic cell by patterning semiconducting polymers and inorganic semiconductors around each other at the nanometer length scale. Summer students will either develop techniques for self-assembling the nanostructures, study charge transport in polymer chains that are confined in nanopores, study exciton diffusion and energy transport in polymers or study how modifying the organic-inorganic interface affects electron transfer.
Professor Paul McIntyre
“Dielectric Materials and Surface Functionalization for Nanowire BioFETs”
For this project, an undergraduate summer researcher will work with a current PhD student in Prof. McIntyre’s Laboratory on a project related to nanoscale biomolecular sensors. The undergrad researcher will investigate different means of functionalizing and deactivating HfO2 and SiO2 surfaces on Si and Ge nanowires for binding of analyte molecules in aqueous solutions. Electrochemical measurements of impedance, Auger and photoelectron spectroscopy, and scanning probe studies will be used to assess the effects of different surface layers on device capacitance and surface chemistry.
Professor Nicholas Melosh
“Direct Visualization of Protein Conformation in Electric Fields”
The Melosh group is investigating the effects that electrical fields can have upon bio-materials and proteins. We have recently demonstrated that electrical fields can activate/deactivate the polymerization of the cytoskeletal protein actin based upon the enhanced ion concentrations (particularly Mg2+) at the electrode surface. However, a number of questions arise about how biomaterials and proteins behave at the surface of a charged electrode. Electrostatic theories such as the Poisson-Boltzmann equation cannot account for finite sizes of ions or proteins, and cannot handle highly multivalent species, as most proteins are. Efforts have been made to adapt these theories to take these considerations into account, however without hard experimental evidence it is unclear if these approaches are accurate or not. The summer student will be responsible for adapting our existing microscopy equipment to make the Fluorescence Interference Contrast (FLIC) measurements, and determining whether our results match existing theoretical models. After initial demonstration of the system, the student will make measurements on a series of fluorescent molecules, ranging from monovalent small molecules to large, multi-valent proteins. From this systematic trend in size to charge, we will be able to compare to the expected exponential distribution of charged ions. It may be found that the highly charged proteins form an immobile layer on the electrode, completely passivating it, which would confirm more recent theories incorporating ion-correlation effects.
Professor William Nix and Professor Seung Min Han
“Nanomechanical Properties of Materials”
Professors William D. Nix and Seung Min Han are engaged in studies of the nano-mechanical properties of materials using the nanoindenter as the primary tool. Current work involves the compression testing of sub-micron sized pillars of various crystalline materials to understand why the mechanical properties of materials in small volumes are so different from those of bulk materials. We make the pillars using the focused ion beam machine to etch pillar geometries from either bulk or thin film materials. The summer student engaged in this project would have the chance to assist in the fabrication of these nanomechanical structures and to mechanically test them using the nanoindenter fitted with a flat-ended diamond punch. Data analysis, simple modeling and other kinds of microstructural characterizations will be a part of this project.
Professor Alberto Salleo
“Doped ZnO Nanowires for Transparent Electrodes for Organic Solar Cells”
The student will perfect the colloidal growth of ZnO nanowires by controlling synthesis temperature, time and presence of surfactants. The ZnO nanowires will be suspended in a solvent and spin-cast on glass substrates to form uniform films. The electrical properties of the films will be characterized as a function of synthesis and processing conditions. The student will use canning electron microscopy to characterize the film morphology. Electrical and optical measurements will be performed as well. If successful, the project will culminate with the fabrication and characterization of an organic solar cell.
Professor Robert Sinclair
“FIB and SEM of Nanomaterials”
This research project will compare the relative merits of the scanning electron microscope, focused ion beam/scanning (transmission) electron microscope, and transmission electron microscope for characterizing the structure of nanomaterials, especially nanoparticles and nanowires. Magnetic nanoparticles for medical application such as cancer detection will be synthesized and characterized by these advanced microscopes.
Professor Shan Wang
“Characterization and Application of Magnetic Nanoparticles for Preconcentration of Protein Targets and Cancer Diagnosis”
Fabrication and characterization of monodisperse, synthetic magnetic nanoparticles with a mean size of 50-100 nm and with tunable physical properties. These particles have potential application in ultrasensitive detection of protein targets for cancer diagnostics, magnetic sorting, andmagnetic resonance imaging (MRI) contrast enhancement. Nanoimprinter and physical vaporation deposition will be employed in this project.