Associate Dean, College of Science and Engineering
Associate Director, MSEC
Professor, Department of Chemistry and Biochemistry
Postdoctoral Fellow, Baylor University (1975-77)
Ph.D. Physical Chemistry, Baylor University (1975)
M.S. Physical Chemistry, Baylor University (1974)
B.S. Chemistry, Tarleton State University (1972)
Dr. Beall’s first job out of graduate school was at Oak Ridge National Laboratory where he conducted research on the environmental fate of actinides originating from the civilian nuclear fuel cycle. He then moved to industry for 21 years during which he served as researcher, group leader, technical director, and vice president for a number of different companies and also founded his own company. The central theme of the research conducted during this period was applications of surface modified clay nanoparticles in paint, cosmetics, grease, pharmaceuticals, cat litter, water treatment, and polymers. He has over 60 publications in refereed journals and 44 US patents in his name. Dr. Beall co-edited the first book written on polymer/clay nanocomposites in 2000 and just published the second on the subject in 2011 coauthored with Dr. Clois Powell. Dr. Beall is well known for his work on nanoparticles (especially smectic type of nanoparticles) and their surface modification and application in a multitude of application areas. Recent research interests include low cost synthesis of graphenes and other 2-D systems. He is currently Full Professor in the department of Chemistry and Biochemistry, Formosa Endowed Chair, Director of the Center for Nanophase Research, Associate Director of the Materials Science, Engineering, and Commercialization program, and Associate Dean of Research and Commercialization for the College of Science at Texas State University. Dr. Beall is also currently serving as an Adjunct Professor at Lamar University in the department of Chemical Engineering, science advisor and adjunct professor for Al-Farabi Kazakh National University, and Distinquished adjunct professor for King Abdulaziz University, SA.
The major focus of my research over the past two decades has centered on non-spherical nanoparticles and nanocomposites made from them. The research on non-spherical nanoparticles includes synthesis, surface modification, self assembly, and characterization. The research on nanocomposites has focused on gaining a fundamental understanding of the critical factors needed to form a true nanocomposite and the mechanisms behind the extraordinary characteriatics exhibited by them. The nanoparticles studied in my research includes smectite clays, hydrotalcites, halloysites, attapulgites, single walled carbon nanotubes, multi-walled carbon nanotubes, graphene, and other 2-D materials developed in my lab . My research has also actively employed molecular modeling to guide and interpret much of the research.
Synthesis of Nanoparticles
Currently we have active synthesis programs ongoing on several different nanoparticles that will continue including;
1. Synthesis of smectic clays with varying charge density and redox active isomorphous substitution. These studies are aimed at probing the fundamental role of charge density in intercalation and exfoliation in nanocomposites.
2. Synthesis of hydrotalcites at varying charge density and redox active substitutions in order to explore the role of charge density in the formation of nanocomposites.
3. Synthesis of carbon nanotubes on unusual substrates to understand better the mechanisms of growth.
4. Synthesis of graphene from natural materials (patent pending). The goal of which is to develop cheap bulk methods to produce graphene and functional graphene.
5. Functionalization of graphene to enable nanocomposite formation.
6. Synthesis of a new family of 2-D materials that exhibit unusual electrical and magnetic behavior. These materials are the subject of intellectual property that is in process and therefore will not be detailed here.
7. Self assembly of nanoparticles through surface modification to create hierarchical structures that generate various functionalities.
One of the critical factors in making a proper nanocomposite is adjusting the surface character of the nanoparticle to match that of the polymer of interest. This has been a major area of focus of my research and will continue to be. The areas of current and future research includes;
1. Ion-dipole surface modification of nanoparticles. This has been a technique that has been pioneered in my group and continues to yield new route to nanocomposites.
2. Surface sorption of polymers on nanoparticles. This technique has also been developed heavily in my group and works well on a large variety of nanoparticles. We have only scratched the surface in this area.
3. Edge treatment through chemical coupling reactions. This approach appears to be quite effective at removing some of the kinetic barriers to intercalation. This has been explored extensively for smectites but much work on other nanoparticles is needed.
In most of these non-spherical nanoparticles one of the critical factors is aspect ratio. Currently there is no direct method to measure the particle size and aspect ratio directly in suspensions. We are currently developing a new light scattering method that will yield both parameters.
The studies of nanocomposites cover two broad areas of the essentials of nanocomposite formation and understanding of the mechanisms behind the characteristics of nanocomposites.
Parameters Important in Forming Nanocomposites
The research in this area is concentrating on quantifying the thermodynamics of intercalation and exfoliation in nanocomposites. Current studies are concentrating on small molecule intercalation enthalpic interactions which will hopefully give a good basis to unravel the enthalpic and entropic contributions in the more complex polymer cases.
In addition recent work on the interaction of nanoparticles with DNA and proteins as well as toxicity of nanoparticles has begun to yield very interesting results.
Theory of Nanocomposite Properties
Some properties of nanocomposites have been explained to a certain extent by conventional composite theories. There however are many properties that still can’t be explained. In my lab a theory of constrained polymer appears to potentially offer a very broadly applicable explanation of nanocomposite properties. The theory requires further investigation and refinement.
The research in this area covers the broad areas of nanocomposites application in engineering composites, energy, barrier materials, biocomposites, flame retardancy, and drug delivery.