Green Energy Technology Projects - 2015
Adapted from X. Chen, L. Liu, P.Y. Yu, S.S. Mao, Science 331(2011) 746.
Visible Light Photocatalysis for Biofuels SynthesisFaculty
Mentor: Fuat E. Celik
Graduate Student Mentor(s): Deniz Dindi, Ashley Pennington
Project Description: As an inexhaustible source of energy, harnessing solar radiation is an appealing goal in renewable energy production. In addition to well-known photovoltaic and solar thermal routes, photons can also promote catalytic reactions in semiconductor materials. Amongst semiconductors, TiO2 is very stable under photocatalysis conditions. Several photocatalytic reactions have been reported on TiO2 and TiO2-supported transition metals. However, with a large band gap (3.2 eV), TiO2 only absorbs ultraviolet light. This project will investigate methods for creating photocatalysts based on TiO2 that are active under visible light irradiation.
Chemical Bio-electrochemical systems for enhanced remediation towards energy recovery
Mentor: Nicole Fahrenfeld
Project Description: Traditional methods for remediating contaminated sediments require substantial energy inputs to supply the electron donors/acceptors needed to facilitate biodegradation of contaminants. A bio-electrochemical approach is appealing because it could improve electron donor/acceptor delivery and offer the opportunity for energy capture, rather than serving as an energy sink. Bench scale bio-electrochemical systems will be prepared and performed to determine the potential for this sustainable remediation technique in sediments with crude oil contamination. This work builds off Dr Fahrenfeld’s research on oil biodegradation and sits at the interface of chemistry, biology, and physics.
Energy Harvesting with Inflatable Windbelts
Faculty Mentor: Aaron Mazzeo
Graduate Student Mentors: Jingjin Xie and Ke Yang
Project Description: This project will involve running experiments that harvest electrical power from wind flowing across a flapping belt. The flapping belt has magnets attached to it, which move relative to wound coils to produce electrical current. Previous windbelts have shown potential as low-cost mechanisms for harvesting energy, and this project adds a new capability of tuning the shape of the belt with embedded inflatable bladders. The idea is that by changing the geometry during use, it might be possible to morph the geometry to accommodate varied flows. The student will have the opportunity to continue work carried out last summer through the GET UP program to address and learn about a variety of engineering challenges/opportunities, which include: creeping of the belt under tension, reduction of the mass of the belt, designs for inflatable structures that significantly alter the aerodynamic properties and energy harvesting, and accurate calculations of generated power and overall efficiency.
Sustainable Lightweight Materials
Faculty Mentor: Richard Riman
Graduate Student Mentor(s): Ryan Anderson
Project Description: Components used in lightweight aerospace, automotive, and insulation applications are often composed of materials such as porous metals and polymer foams. While these materials have adequate properties for their application, they have considerably large CO2 footprint and embodied energy values, making them unsustainable. The objective of the proposed research project is to fabricate and study alternative ceramic-based composite lightweight materials with lower CO2 footprint and embodied energy using a novel green materials process.
The student will learn how to perform ceramic processing of mineral-based materials, a low-temperature material solidification process, and basic sustainability calculations. The student will also use equipment such as XRD and TGA.
Project : Few-layer graphene synthesis using pulsed laser deposition
Faculty : Stephen Tse
Graduate Student Mentors : Hua Hong
Project Description: Graphene, as a rising star in the fields of material science and solid-state physics, has drawn enormous research interest since this two-dimensional (2D) carbon lattice was first presumed to exist in 2004. By using our novel flame synthesis method, we are able to grow monolayer graphene on copper substrates at high growth rates in open-atmosphere environments. Our innovative multi-element inverse-diffusion-flame burner produces radially uniform post-flame temperatures and species, along with downstream methane direct injection near the substrate. Systematic studies of the effects of growth temperature, species, and deposition time are conducted. The flow field temperature and species profiles are characterized using in-situ laser-based diagnostics. Our novel flame-burner also provides us great opportunity to experimentally synthesize graphene doped with organic and metal molecules. Raman spectroscopy, SEM, TEM and XPS are employed to study the quality and morphology of these graphene-based materials.
Representative scanning electron microscope images of nanoporous silver films with different porosities prepared by a thermally-assisted substrate de-wetting method.
Project: Nanoporous Metals for Polymer Optoelectronics: Large-Area Fabrication and Optical Characterization
Faculty: Deirdre O’Carroll
Graduate Student Mentor: Zeqing Shen
Project Description:To enable next-generation, nanostructured organic polymer semiconductor-based optoelectronic devices, high-throughput, large-area, low-cost methods to pattern metal electrode surfaces are necessary. Additionally, conjugated polymer chain orientation has shown great influence on charge-carrier mobility and overall performance of large-area organic optoelectronic devices . Although, numerous prior studies have characterized polymer chain alignment in bulk or thin-film environments, the chain organization behavior of semiconducting conjugated polymers in nanostructured or confined environments is expected to be very different from that in planar or bulk formats and could lead to improved optical or electrical properties . In this project, we develop fabrication and characterization techniques for large-area nanoporous metals (NPMs) and investigate their use as a platform to control or modify conjugated polymer chain alignment for optoelectronic applications. We wish to investigate how the structure of the patterned metal electrode and the resulting changes in polymer chain organization can improve the light-emitting properties of the polymer relative to those on planar metal electrode surfaces.
References: M. Aryal, K. Trivedi, W. Hu, ACS Nano. p3085 (2009), K. Shin, S. Obukhov, J. T. Chen, J. Huh, Y. Hwang, S. Mok, P. Dobriyal, P. Thiyagarajin, T. P. Russell, Nature Mater. 6, p961 (2007). K. R. Williams, K. Gupta, M. Wasilik, J. Microelectromech. Sys. 12 (2003). L. Qian, X. Yan, T. Fujita, A. Inoue, M. Chen, Appl. Phys. Lett. 90, p153120 (2007).
Project: Developing glasses for their application in ZEBRA batteries
Faculty: Ashu Goel
Project Description: ZEBRA battery (Technical name: Na-NiCl2 battery) was invented in 1985 by the Zeolite Battery Research Africa Project (ZEBRA) group led by Dr. Johan Coetzer in South Africa. ZEBRA battery operates at ~250 oC and utilizes molten sodium aluminumchloride (NaAlCl4) as the electrolyte, molten sodium as negative electrode and nickel in discharged state and nickel chloride (NiCl2) in charged state as positive electrode. Since both NaAlCl4 and Na are liquid at the operating temperature, a sodium-conducting beta-alumina (Al2O3) ceramic is used to separate the liquid sodium from molten NaAlCl4 while alpha-Al2O3 is used as an insulating collar and a suitable glass based material is applied to join the two ceramic components. The purpose of the glass seal is to maintain a hermetic and robust sealing between alpha- and beta-Al2O3 ceramic components in the battery while being exposed to hostile alkali- and halide vapor rich environment at operating temperatures. The primary requirements for designing a suitable glass sealant for ZEBRA batteries are as follows: minimum thermal expansion mismatch between glass and ceramic components; high thermal shock resistance; high chemical resistance towards alkali vapors and low electrical conductivity.
PZT-Carbon multiwalled epoxy thick film with graphene monolayer. 
Project: Percolative Dielectric Materials for Energy Storage Applications
Faculty: Kimberly Cook-Chennault
Graduate Student Mentors: Udhay Sundar and Wanlin Du
Project Description: Electrical energy storage plays a key role in electronics, stationary power systems, hybrid electric vehicles and pulse power applications. Traditionally, bulk ceramic dielectric oxides have been used for these applications, though they suffer from inherently low breakdown field strength, which limits the available energy per unit mass (energy density) and increases the dielectric loss. On the other hand, polymers have high break down field strengths, low dielectric losses and can be readily processed into thin films, but suffer from relatively low dielectric permittivity, and thus low energy densities. This project focuses on development of materials that can be applied to sub-micrometer scale commercial and industrial devices such as, high density DRAM (dynamic access memory), non-volatile memory (NRAM) and capacitors. It is well known that coupling polymer and a dielectric constant material into a composite may address some of the aforementioned challenges, though the mechanisms that lead to higher dielectric constants and minimal dielectric losses are not well understood. Hence students will fabricate and analyze composite dielectric materials with the aim of understanding the mechanisms that lead to higher dielectric constants and higher breakdown field strengths.
 Multi-Walled Carbon-Nanotube Based Flexible Piezoelectric Films with Graphene MonolayersS Banerjee, R Kappera, KA Cook-Chennault, M ChhowallaEnergy and Environment Focus 2 (3), 195-202
Project: Bulk thermoelectric characterization setup
Faculty: Mona Zebarjadi
Graduate Student Mentor(s): Xiaobing Zhang
Project Description: Thermoelectric power generators are used to directly convert thermal energy into electricity and they can be used in waste heat recovery and solar thermal energy conversion. The efficiency of the thermoelectric devices, highly depend on the quality of the materials used. Three coefficients, electrical conductivity, thermal conductivity and Seebeck coefficient are determining the materials efficiency. In the last year GET UP project we have assembled a setup to characterize the Seebeck coefficient . This year, we will complete the setup enabling measurements of electrical conductivity.
Project: Design and optimization of an absorption refrigerator
Faculty: Keivan Esfarjani
Project Description: In the early 1900's, Szilard and Einstein developed 3 patents on absorption refrigerators in order to avoid the use of toxic gases in compressor-based refrigerators. In addition, the required source of energy to pump heat is a heat source instead of electricity. In other words, an absorption refrigerator does not require electricity, has no moving mechanical parts, and works only with a hot source such as fire!
This project has 2 parts which can be done independently
1)Performing a systematic search over the absorption and coolant materials and their range of applicability, in order to identify working pairs and their temperature range of operation, as well as their safety and cost
2)Based on the above classification, a choice of the materials will be made, and an absorption refrigerator will be designed accordingly, using a CAD software.
Project: Piezoelectric Properties of Porous PVDF Films
Faculty: Shahab Zadeh
Project Description: Polyvinylidene fluoride (PVDF) is a polymeric piezoelectric and pyroelectric material and its copolymers with trifluoroethylene (TrFE) or tetrafluoroethylene (TFE) are well known typical ferroelectric polymers. PVDF has a large piezoelectric (thickness mode) coefficient (–30 pC/N) compared to other bulk polymers. It is suggested that by reducing the Young’s modulus of a material, its piezoelectric coefficient may increase several folds. In this project, we will examine this hypothesis by fabricating thin porous PVDF films of various thicknesses. We then pole them under external electric fields and will measure their piezoelectric coefficients. By measuring compressive Young’s modulus of the fabricated samples, we will determine property-function correlation (E vs. d33) for such materials at room temperature. These porous polymer films have great potential for use in biosensors as well as in energy harvesting devices.
Project: Designing Energy-Efficient Micro-Switches
Faculty: Y. Pan & F. Yu
Project Description: In this work, students will learn about a next-generation transistor candidate—micro-electro-mechanical (MEM) switch, which can provide for zero static power consumption and potentially very low dynamic power consumption due to its zero off-state leakage current and abrupt turn-on behavior.
Students will learn about how to perform finite-element-method (FEM) analysis using CoventorWare simulation software, to design/fabricate MEM switches.