Samson A. Jenekhe
Boeing-Martin Professor of Engineering and Professor of Chemistry
Contact Information
| 363 Benson Box 351750 Seattle, WA 98195-1750 |
Phone: 206-543-5525 Fax: 206-685-3451 Email: jenekhe@cheme.washington.edu |
Education
B.S., Michigan Technological University, 1977.
M.S.Ch.E., University of Minnesota, 1980.
M.A., University of Minnesota, 1981.
Ph.D., University of Minnesota, 1985.
Research Interests
- Organic electronics and optoelectronics, including thin film transistors, solar cells, and LEDs.
- Self-assembly and nanotechnology, including block copolymers, nanowires, and multicomponent self-assembly.
- Polymer science, including synthesis, processing, properties, and photonic applications.
Electroluminescent Polymers for Displays, Self-Assembling Polymer Systems, Polymer Device Engineering, Tunable Optical Polymer Systems, and Polymer Nanophotonics
One of Professor Jenekhe's main research interests focuses on electronic, optoelectronic, and photonic phenomena in polymers. Fundamental understanding of these phenomena and the related electroactive and photoactive properties in synthetic polymers is essential to their applications in diverse areas of technology ranging from imaging, photodetectors, batteries, sensors, electrochromic devices, and solar cells to light emitting diodes for flat panel displays. One perennial problem is elucidation of the structural origins of electronic and photonic properties of polymers; another is how to improve or control the efficiencies of the photophysical and charge transport processes. Our general approaches to these problems include the design and synthesis of new polymers, physical and photophysical measurements, structure-property correlations, computational modeling, thin film processing, and polymer device engineering.
In one area, we are exploring how the electronic, molecular, and supramolecular structures and morpholoty of conjugated polymers influence their photoconductivity, luminescence, and charge transport properties. Model systems include homologous series of conjugated oligomers, blends of conjugated polymers, and derivatized conjugated polymers. Aggregation of conjugated polymers which can lead to diverse phenomena is under study, including the formation of excited-state and ground-state complexes which can significantly modulate the optical and photoelectronic properties of the materials. Our studies in the area of polymer thin film device engineering are aimed at addressing the fundamental and engineering issues involved in developing and producing high performance and durable electronic and optoelectronic devices (e.g. light-emitting diodes, photodetectors, thin film transistors, photovoltaic cells, sensors, etc.) from organic and polymeric materials. These issues include polymer thin film deposition processes, characterization of the electronic, optical and mechanical properties of polymer thin films and polymer/polymer, and polymer/metal interfaces, and the fabrication and evaluation of multilayer polymer thin film devices. Recently discovered finite size effects on nanoscale semiconducting polymer thin films and devices also require further study.
The study of synthetic self-assembling nanostructures and microstructures of well defined size, shape, and function represents another major research effort in the group. We are exploring molecular recognition-directed self-assembly of macromolecular building blocks into two- and three-dimensional functional mesostructures. Our initial studies of hydrogen-bonding rod-coil block copolymers have demonstrated the supramolecular self-assembly of diverse discrete objects (vesicles, tubules, micelles) with size scales in the 50 nm to 200 mm range and electronic and photonic functions. Major challenges include synthesis of complementary building blocks, controlled self-assembly of nanostructures, physicochemical characterization of large macromolecular assemblies, elucidation of structure-function relationships and exploitation of self-assembling electronic and photonic polymers in molecular devices, nanotechnologies, photonic band gap structures, and other applications.
Selected Recent Publications
Tonzola, C. J., Kulkarni, A. P., Gifford, A. P., Kaminsky, W., and Jenekhe, S. A., “Blue-Light-Emitting Oligoquinolines: Synthesis, Properties, and High-Efficiency Blue-Light-Emitting Diodes,” Advanced Functional Materials, 6, 863-874 (2007).
Hancock, J. M., Gifford, A. P., Tonzola, C. J., and Jenekhe, S. A., “High-Efficiency Electroluminescence from New Blue-Emitting Oligoquinolines Bearing Pyrenyl or Triphenyl Endgroups,” Journal of Physical Chemistry C, 111, 6875-6882 (2007).
Briseno, A. L., Mannsfeld, S. C. B., Lu, X. M., Xiong, Y.J., Jenekhe, S. A., Bao, Z. N., and Xia, Y. N., “Fabrication of Field-Effect Transistors from Hexathiapentacene Single-Crystal Nanowires,” Nano Letters, 7, 668-675 (2007).
Briseno, A. L., Mansfield, S. C. B., Reese, C., Hancock, J. M., Xiong, Y., Jenekhe, S. A., Bao, Z., Xia, Y., “Perylenediimide Nanowires and Their Use in Fabricating Field-Effect Transistors and Complementary Inverters,” Nano Letters 2007, 7, 2847-2853.
Jenekhe, S. A., Alam, M. M., Zhu Y., Jiang, S. Y., and Shevade, A. V., “Single-Molecule Nanomaterials from Pi-Stacked Side-Chain Conjugated Polymers,” Advanced Materials 19, 536-542 (2007).
Zhu, Y., Gibbons, K. M., Kulkarni, A. P., and Jenekhe, S. A., “Polyfluorenes Containing Dibenzo[a,c]phenazine Segments: Synthesis and Efficient Blue Electroluminescence from Intramolecular Charge Transfer States,” Macromolecules, 40, 804-813 (2007).
Babel, A., Zhu, Y., Cheng, K. F., Chen, W. C., Jenekhe, S. A., “High Electron Mobility and Ambipolar Charge Transport in Binary Blends of Donor and Acceptor Conjugated Polymers,” Adv. Functional Materials 2007, 17, 2542-2549.
Selected Most Cited Publications
JJenekhe, S. A. and Osaheni, J. A., “Excimers and Exciplexes of Conjugated Polymers, Science, 265, 765-768 (1994). (507)
Jenekhe, S. A. and Chen, X. L., “Self-assembly of Ordered Microporous Materials from Rod-Coil Block Copolymers,” Science, 283, 372-375 (1999). (391)
Jenekhe, S. A. and Chen, X. L., “Self-Assembled Aggregates of Rod-Coil Block Copolymers and their Solubilization and Encapsulation of Fullerenes,” Science, 279, 1903-1907 (1998). (371)
Zhang, X. J. and Jenekhe, S. A., “Electroluminescence of Multicomponent Conjugated Polymers. 1. Roles of Polymer/Polymer Interfaces in Emission Enhancement and Voltage-Tunable Multicolor Emission in Semiconducting Polymer/Polymer Heterojunctions,” Macromolecules, 33, 2069-2082 (2000). (135)
Kulkarni, A. P., Tonzola, C. J., Babel, A., and Jenekhe, S. A., “Electron Transport Materials for Organic Light-Emitting Diodes,” Chemistry of Materials, 16, 4556-4573 (2004). (129)
Jenekhe, S. A., Lu, L.D., and Alam, M. M. “New Conjugated Polymers with Donor-Acceptor Architectures: Synthesis and Photophysics of Carbazole-Quinoline and Phenothiazine-Quinoline Copolymers and Oligomers Exhibiting Large Intramolecular Charge Transfer,” Macromolecules, 34, 7315-7324 (2001). (126)
Recent M.S. Theses
Recent Ph.D. Dissertations
