CBE - People

Biography

Emmanuel P. Giannelis is the Walter R. Read Professor of Engineering. In addition to his primary appointment in Materials Science and Engineering, Giannelis is a member of the Fields of Applied and Engineering Physics and Chemical and Biomolecular Engineering. His research interests includeNanomaterials for Energy, Biomedical, Transportation, Infrastructure, and Environmental Applications. His group is internationally recognized as one of the leading groups in polymer nanocomposites.

Giannelis is a member of several organizations and serves or has served on the editorial boards of Small, Chemistry of Materials and Macromolecules. He has co-organized half a dozen conferences or symposia on Nanocomposites and has delivered more than 400 Invited Talks and Seminars. He is the author or co-author of more than 200 papers and 11 patents. He is a member of several professional organizations and a corresponding member of the European Academy of Sciences. He is a highly cited author in Materials Science (http://www.ISIHighlyCited.com) and he is listed as one of the top 25 cited authors on Nanotechnology by ISI (http://www.esi-topics.com/nano/index.html).

Research Interests

Efforts to manipulate and control materials at the nanoscale have taken center stage in research activities all over the world. These efforts are motivated, in part, by the realization that nanoscale materials often exhibit properties that are dramatically different from their microscale counterparts. In that respect polymer nanocomposites synthesized by adding nanoparticles such as nanoclays into the polymer matrix have attracted considerable attention in recent years. The goal is to develop lightweight composites with potentially superior mechanical, rheological, electrical, thermal and biomedical properties by taking advantage of the high surface area available in the nanoparticles and the accompanied synergistic effects with the polymer matrix. Over the years are group has been active and contributed to these efforts. Specific directions have included 1) chemical synthesis and processing of nanocomposites with controlled structure and interface properties 2) characterization of interface structure and dynamics, and 3) delineation of molecular and structural features that contribute to the mechanical and physical properties of the materials. All previous efforts have focused on fine-tuning the polymer/nanoparticle miscibility in order to achieve full nanoparticle dispersion. More recently we have become interested in manipulating nanoparticles into organized assemblies by exploiting depletion interactions/phase separation of nanoclays and other nanoparticles. Finally, we are devoting a significant part of our recent efforts into the development of "solvent-free" or "dry" nanoparticle fluids. These new hybrid systems consist of inorganic nanoparticle cores functionalized with a charged corona. Because of their molecular architecture they flow like liquids but possess no volatility. Furthermore, because of their hybrid nature their optical, magnetic, electronic, biological and other properties can be fine-tuned to meet potential applications.

Nanocomposites

Addition of nanoclays or other nanoparticles into various polymers to produce nanocomposites has been extensively utilized in an attempt to enhance the mechanical, physical and thermal properties of polymers. Despite considerable progress, challenges with miscibility/poor dispersion and poor interfacial strength have prevented nanocomposites from realizing their full potential. Furthermore, the high performance of glass fiber composites is still beyond the capabilities of nanocomposites. Nanoparticles such as nanoclays can function as structure and morphology directors or introduce new energy dissipation mechanisms, all of which can lead to enhanced properties. Several ongoing projects focus on the science and applications of nanocomposites with particular emphasis on understanding the underlying mechanism(s) of property development.

Nanoparticle Fluids (Nanofluids)

Nanoparticle suspensions in different solvents (sometimes termed nanofluids) have emerged as an exciting new R&D area because of their unique wetting and transport properties. Until recently nanofluids have been composed of nanoparticles (pristine or surface modified) typically suspended into a solvent. Recently, we have developed a series of functionalized nanoparticles that exhibit liquid-like behavior in the absence of a diluent or solvent. These nanoparticle fluids possess flow properties (viscosity and diffusivity) that are remarkably similar to those of simple molecular liquids. Unlike simple liquids, however, they do not possess a measurable vapor pressure dramatically increasing the range of potential applications. In addition, since the nanofluids are hybrid systems, they can be engineered to combine specific properties (e.g. refractive index, viscosity, conductivity, magnetic properties) that are difficult or impossible to achieve with molecular-based fluids.

Flexible Electronics

The drive towards ubiquitous electronics requires fundamental shifts in our approach to microelectronic fabrication as well as new advances in materials and processing technologies. One of the challenges is adopting state-of-the-art capabilities demonstrated for rigid substrates to platforms consistent with ubiquitous applications such as flexibility and low cost. For large area electronics, low cost manufacturing, roll-to-roll (R2R) processes, and printing technologies will be required. In that respect, challenges continue in developing processing technologies compatible with the low thermal budgets required for such flexible, polymeric substrates. In this project we are developing new methods and tools for depositing various functional coatings and films on flexible, low thermal budget substrates using laser annealing. Our objective in this program is to provide a better understanding of the role of the different constituents in the system and how they might affect phase behavior and transport properties such as conductivity, diffusivity, and fluidity.

Nanobiohybrids

Advances in identification of biomarkers and pharmaceutical targets driven by discoveries arising from genomics are revolutionizing medicine by developing novel diagnostic and therapeutic tools. While the possibilities for designing such tools are unlimited, they are only as good as the safety and efficacy of the method used for delivery. Thus, efficient and safe targeting has emerged as a widely recognized, critical challenge. The long term goal of this program is to develop nanoparticle-based tools for molecular targeting and imaging.

Nanohybrid Membranes for Fuel Cells

An integral part of a fuel cell is the electrolyte, whose function is to maximize ionic mobility in order to increase efficiency, while impeding cross-over of the fuel or any contaminants. Additionally, the electrolyte must be stable towards oxidation, reduction or hydrolysis over a broad temperature and humidity range. The objective of this program is to design and develop nanohybrid membranes for fuel cell applications. Nanostructuring can be exploited to produce fuel cell membranes, which combine decreased fuel crossover, reduced swelling, and higher conductivity leading to better overall fuel cell performance.