Prospective Students
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
“Nanoscale Design of Biomaterials for Nerve Regeneration”
A promising new approach to designing nanoscale materials involves mimicking the tools Nature has developed to create functional polymers with molecular level precision. The materials we design and synthesize are composed of engineered protein polymers created by bacterial hosts. By precisely altering the chemical composition of the polymers, we can tune the mechanical properties, self-assembly features, degradation profiles, and biological interactions of these materials. In this project, the student will learn how to synthesize protein-polymers, fabricate them into scaffolds, and test their mechanical properties. These scaffolds will be used in future studies that correlate nerve cell growth and behavior with scaffold mechanical properties
Professor Aaron Lindenberg
“Femtosecond nanoscale structural dynamics”
The goal of this summer project is to carry out experiments probing the dynamical behavior of nanoscale materials in real time at femtosecond resolution, and to elucidate the underlying transformation mechanisms. Students will gain experience using ultrafast lasers, x-ray characterization techniques, and nanofluidic cells. Experiments will be carried out both on campus and at the Stanford Linear Accelerator Center.
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
“Designing Heterogeneous Catalysts for Cleaner Energy: Nanostructured Metal Oxides and Semiconductors”
This project would involve collaboration with a graduate student and postdoc who are investigating "designer" catalysts for electrolysis or photo-electrolysis of water. The goal is combine ultrathin metal oxide layers that are catalytic for oxygen generation with low bandgap semiconductors that are effective absorbers of solar radiation. The undergraduate will characterize chemical reactions that occur at both the metal oxide/semiconductor nanostructured anode and the metal cathode in water for various buffer solution pH values and ionic additives. This may involve either materials characterization (e.g. XPS, AFM, SEM) or current-voltage measurements.
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 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
“Physical fabrication and characterization of synthetic magnetic nanoparticles”
The project is aimed at fabricating iron oxide nanoparticles in dextran shells from water phase solution synthesis. Different synthetic routes will be explored to arrive at a formulation which is uniform, stable, and superparmagnetic. Their performance for cancer detection will be evaluated on the magneto-nano protein chip being developed in Wang Group. The nanoparticles will also be characterized by tools like scanning electron microscopy (SEM).