 Dr. Wayne E. Jones is an Associate Professor, Inorganic & Materials Chemistry and on his spare time he is the Director Graduate Studies in Chemistry, Director, Center for Learning and Teaching and General Chair, ACS Northeast Regional Meeting 2006. He has received his B.S. from St. Michaels College, his Ph.D. from University of North Carolina, Chapel Hill. Additionally, he has received a Postdoctoral Fellowship from University of Texas, Austin, a Visiting Professor from University of Pennsylvania, 2000, and the Chancellor's Award for Excellence in Teaching, 2001
Our research group's interests involve the study of photo-induced electron and energy transfer processes in inorganic and polymer systems. By combining novel synthetic strategies with modern electrochemical and spectroscopic techniques, we gain a better understanding of fundamental processes which occur in all of chemistry including electron transfer, energy transfer, excited state reactivity, and materials design at a molecular level. The focus of our efforts is the design and study of molecular wires and devices. These nanomaterials provide a foundation for fundamental investigations as well as opportunities for new applied technologies. The projects briefly outlined below fall into three areas under the theme of molecular wires and are supported by grants from NIH, NSF, SRC, NIST, New York State Center for Advanced Technology (IEEC), and industrial partners.
One targeted area of interest involves application of electronic and photonic polymers to specific devices such as sensors. We have prepared a series of fluorescent polymer chemosensor materials. This project takes advantage of electronic communication along conjugated polymer molecular wires to provide enhanced detection of nanomolar quantities of transition metals in solution. Initially supported by the National Institutes of Health, we are preparing more reversible and water sensitive versions of this exciting new class of materials. Of particular interest is the non-linear quenching response in these polymers, which make them significantly more sensitive than monomeric sensors. We have developed a unique mathematical model that incorporates both static quenching and dynamic energy transfer. Fitting of the fluorescence quenching data allows distinction between Dexter and Forster energy transfer mechanisms. The synthetic strategy allows for variations in the receptor, receptor loading, and polymer backbone conjugation. Recent work has involved design of more selective receptors based on hemi-labile ligands. This also involves detailed photophysical investigations of a series of transition metal complexes based on this flexible Lewis basic ligand. We have also developed a new class of conjugated polymers that “turn-on” their fluorescence in the presence of specific analytes.
The second area of emphasis involves the design of conducting molecular wires which continues to be a fascinating target of chemistry, physics, and materials science and represents the third area under the molecular wire theme. We have been applying a non-mechanical electrostatic polymer processing procedure to prepare nanofibrous materials with diameters of < 100 nm. Nanofibers prepared to date include conducting polymers, polymer blends, and layered composite materials of metals, metal oxides, and conducting polymers. In addition to providing a basis for the study electronic effects on a nanometer scale, these materials are also being investigated as sensor materials. Recently, we have demonstrated the use of the Tubes by Fiber Templates (TUFT) approach to create nanotubes of metals, graphitic carbon, conducting polymers, and metal oxides. Characterization by SEM, TEM, XRD, and FTIR show uniform tubes with 50-1000 nm inner diameter and wall diameters of 30 - 300 nm. With the support of grants from SRC and NIST, we have also been looking at the thermal conductivity of these materials in addition to the electrical conductivity. This experimental work is designed to provide direct evidence for enhancements in these properties that have been predicted by modeling studies on nanomaterials recently published by groups at the California Institute of Technology and Columbia. In recent work, we have demonstrated that self-assembled monolayer thin films terminated with transition metal complexes can be used as a reactive surface to initiate conducting polymer thin films by in-situ deposition. This method results in conducting polymers with conductivities that are 1-2 orders of magnitude higher than previously reported from this technique.
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