The RTNN is accepting applications from middle and high school teachers as well as community college educators for its summer RET program: Atomic Scale Design and Engineering.
Up to eleven teachers will be selected to participate in research in nanotechnology labs at NC State, Duke, and UNC-Chapel Hill or in an industry lab. Participants will work in small teams to conduct research in atomic scale design and engineering. Teachers will also gain hands-on experience in the cutting edge techniques and tools used in nanoscale science and engineering within RTNN facilities. All participants will conduct a research study; potential projects are listed below. Teachers will also spend time designing curricular materials to use in their classroom and will share these teaching materials during the program and after they return to their home institution. Participants will have weekly seminars focused on nanotechnology from RTNN faculty and industry leaders. Join us for an interesting summer learning about advances in research, getting involved in your own study, and thinking about new ways to teach science and engineering.
The program lasts for 5 weeks, June 17 – July 19, with follow up during the academic year. Teachers will receive a $5,000 stipend for their work as an RET with additional funding available for curricular materials and travel for lesson plan/curriculum dissemination. The program is for US citizens only and teachers must participate for the entire period of the program. Participants are required to attend all daily and weekly meetings, seminars, field trips, and workshops.
Applications are now closed for the 2019 program. Please check back in early 2020 for information about the summer 2020 program.
Smart Materials Solutions: In this project, teachers would: 1. Characterize micro/nanostructured molds using different microscopy techniques. 2. Conduct nano-imprint lithography at SMS to replicate molds into different polymers. 3. Test for hydrophobicity (contact and sliding angle), and compare results between polymers, nanostructures, and liquids.
Dr. Jacob Jones Lab (NC State): Synthesis of nanoscale ferroelectric thin films
Hafnia (HfO2) is a competitive material with silica (SiO2) for gate dielectrics in nanoelectronic circuitry. When doped with small amounts (~5-10%) of certain elements such as Si or Gd, ultra-thin films of these materials (~10 nm) exhibit a phenomenon known as ferroelectricity. This effect gives the material an ability to store charge without voltage applied and switch charge from positive to negative, useful for nonvolatile memories and ferroelectric field-effect transistors. However, there is not much known about how atomic-scale layering in the processing of these materials is affected by the processing temperature and, in turn, affects the properties of the films. In previous work, the Jones group has evaluated the atomic-scale chemical homogeneity (or lack thereof) in films synthesized at a fixed crystallization temperature using TOF-SIMS. Using these measurements, they are able to show with nanometer precision the chemical distribution through the film thickness. This project will evaluate how thermal treatment affects chemical homogeneity and resulting performance. The hypothesis is that heating the sample will impart thermal energy which homogenizes the sample, thereby improving properties. At too high of temperatures, we hypothesize that the properties will degrade.
Teacher and/or Community College Faculty Component: This research project is designed to give teachers hands-on experience utilizing and controlling the thermal treatment processes of electronic thin films as well as characterizing their resulting structures using techniques like TOF-SIMS. The teachers will be responsible for treating films, learning and applying TOF-SIMS, and measuring ferroelectric properties. The project will lead to optimum conditions for performance of electronic materials
Dr. Ericka Ford Lab (NC State): Nanomanufacturing of Functional Nanofibers
Hazardous waste kits for industrial spills contain absorbent pads and inorganic desiccates. Both materials are used to safely dispose of organic waste and to decontaminate the industrial or laboratory workspace and even the environment. Based on these successes, researchers have studied the use of inorganic particles as adsorbents for wastewater and groundwater decontamination. By combining adsorbing particles onto high surface area textiles, nanoscale adsorbents can be used to the filter water and air that people need daily to live without fear of nanoparticle leaching which can lead to contamination. Chemical vapor deposition is used to deposit inorganic coatings uniformly to porous membranes or textiles; however, this is an expensive technology. Therefore, the research goals of this study on functional, nanoscale fibers are to explore nanomanufacturing techniques that lend themselves towards economic, industrially scalable approaches to advanced filtration.
Teacher and/or Community College Faculty Component: Educators will learn how to fabricate nanofibers using the scalable electrospinning approach. The Ford research lab uses a lab-scale, single needle approach to manufacture nanofibers from solutions of dissolved polymers. The pilot scale manufacturing of electrospun nanofibers will utilize the Elmarco Nanospider. By varying the applied voltage, voltage bias, tip to collector distance, and humidity, researchers can tune nanofiber size and its surface chemistry. Using advanced electron and scanning probe microscopy techniques, educators will measure the diameters of nanofibers and distinguish between nanoscale features. Image mapping techniques including energy dispersive spectroscopy and Time-of-Flight Secondary Ion Mass Spectrometer (TOF-SIMS) will be employed to analyze surface chemistry. Mineral coatings of interest include titanium oxide, manganese oxide, carbonates, and silicates.Techniques that are industrially scalable through the adaptation of traditional textile finishing techniques will be studied. Visiting educators will use a synthetic sol-gel technique to nucleate and grow inorganic coatings along nanofibers and will study the effect of nanofiber chemistry, time, and temperature on the kinetics of sol-gel synthesis. The same parameters are expected to affect the atomic to nanoscale morphology and uniformity of mineral deposits along the nanofibers.
Dr. Philip Bradford (NC State): Patterning of Carbon Nanotube Arrays
Carbon nanotubes (CNTs) grown on solid substrates from catalysts deposited from the vapor phase have not previously been patterned. The ability to pattern CNTs on solid substrates is useful for making hierarchical structures for use in composites and sensors. The challenge in patterning CNTs, where the catalyst is deposited from the vapor phase, is in defining areas where the deposited catalyst will not nucleate CNTs. In this project, the growth substrate will first be patterned and coated with solid materials that will act as CNT nucleation inhibitors. It is expected that thin metal coatings will disrupt the nucleation of CNTs through changing the surface energy and/or through dissolution of the catalyst particle into the metal layers.
Teacher and or Community College Faculty Component: This research project is designed to give teachers hands-on experience in nanofabrication methods of patterning, thin film depositions of metals, and chemical vapor deposition growth of carbon nanotubes. Analysis of the final structures through SEM, AFM, and TEM is expected.
Dr. Stefan Zauscher (Duke): Development of microfluidic devices for blood analysis (Stefan Zauscher, Duke) Quantification of biomacromolecular complexes (lipoproteins, protein/carbohydrates, enzyme/substrate complexes) in blood plasma is challenging. Current techniques rely on time-consuming separation strategies, typically centrifugation, to separate plasma from whole blood, followed by additional separation and/or detection, and require relatively large amounts (~0.5-10 ml) of blood. The Zauscher lab has recently developed an innovative technology based on quartz crystal microbalance (QCM) sensors that has the potential to quickly quantify the concentration of biomacromolecules in plasma while requiring only small amounts (< 50 µl) of blood. In this technology, microfluidic channels are bonded to the surface of a QCM sensor, which allows for i) on-chip blood/plasma separation (blood cells cannot enter the microchannels), ii) increased mass detection sensitivity in liquids (mass is more rigidly coupled to sensor surface), and iii) use of sub-microliter samples. Current research activities are aimed at sensor fabrication and proof-of-concept demonstration of protein capture from blood plasma.
Teacher and/or Community College Faculty Component: Depending on interest and background of the participant, we propose two research projects. Project one is focused on the design of the microfluidic channels and device fabrication. This project will give participants hands-on experience in optimizing the design of the fluidic channels to achieve i) more uniform channel filling and ii) improved on-chip blood/plasma separation. Participants will be able to design, fabricate, and test different microfluidic channel geometries, and will be trained in using photolithographic processes. Characterization of the devices will be accomplished by fluorescence microscopy and image analysis. This project can easily be continued beyond the summer period at Duke University because participants, at their home institutions, can further design channel geometries which then can be fabricated at Duke and tested. Project two is focused on establishing the proof-of-concept for a fast platelet factor 4 (PF4)/heparin complex immunoassay, amenable for detection with the microfluidic QCM. Detection of this complex is of great clinical interest, because the formation of stable PF4/heparin complexes in plasma can trigger heparin induced thrombocytopenia (HIT), a life-threatening allergic response. In this project, participants will develop and test a mass-enhanced detection assay in which gold nanoparticles (GNPs) will be functionalized with biotinylated KKO capture antibodies (targeted to the PF4/heparin complex) and then added with plasma to a PF4-functionalized QCM crystal surface. Specifically, participants will establish the concentration of KKO-antibody conjugated NPs at which the detection sensitivity, for a given surface functionalization density, will be maximal. Participants will be trained in state-of-the-art surface functionalization techniques and exposed to surface characterization techniques including AFM, QCM, and X-ray photoelectron spectroscopy.
Dr. Jim Cahoon (UNC): Vapor-Phase Control of Hybrid Perovskite Materials
Lead halide perovskites of the form APbX3 (A=organic or inorganic cation; X=Cl, Br, or I) are a material class that have garnered substantial interest due to the ability to create high performance photovoltaic and other optoelectronic devices at low cost. Methylammonium lead iodide (MAPbI3) is the prototypical material for perovskite solar cells and is produced by the intercalation of methylammonium ions into a lead iodide crystal lattice. Most often performed in solution phase, this conversion is destructive to the parent morphology and crystallinity. Degradation also occurs quickly in ambient conditions especially at elevated temperatures, resulting in the loss of the organic cation and halide components. Understanding these two processes and developing methods for reducing their detrimental effects is critical for utilizing this high-performance material.
With these processes in mind, we built a custom chemical vapor deposition (CVD) system that features monomethylamine, HCl, HBr, and HI gases. These gases are introduced into a thermal reactor with pressure, temperature, and flow rates all under computer control. Using this system, we will study in a finely-controlled environment the conversion of lead iodide to perovskite, the role of oxygen and heat on the degradation of perovskite, and the healing process of degraded perovskite. To obtain a localized picture of these effects, we will use single-crystalline lead iodide nanowires and microplates grown in-house and macro-scale perovskite single-crystals grown by our collaborators at UNC.
Teacher and or Community College Faculty Component: Through these research efforts, visiting teacher-researchers will be introduced to the exciting and rapidly growing research field of nanoscale perovskite crystals. They will have opportunities in clean sample preparation, metal evaporation, vacuum reactor operation, LabView and MatLab data collection and analysis, handling of samples in inert atmosphere, electron-beam lithography, electron microscopy, energy-dispersive x-ray spectroscopy, atomic force microscopy, and photoluminescence spectroscopy.