Lei Zhai
Polymeric Materials, Surface Science and Engineering

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Assistant Professor of Nanoscience Technology Center and the Department of Chemistry Ph.D., Carnegie Mellon University, 2002 Phone: 407-882-2847 Office: PVL 424 Zip: 32816-0150 E-mail: lzhai@mail.ucf.edu NanoScience Webpage: www.nanoscience.ucf.edu/faculty_zhai.php View Full Curriculum Vita

Research

1) Polyelectrolyte Multilayer Films for Sensing and Tissue Engineering.
Polyelectrolyte multilayer films are assembled on the molecular level, and there is unequaled control of thickness, molecular architecture, and composition. In addition, these films have been shown to coat virtually any surface or geometry, use aqueous based processing, and are extremely easy to produce. These factors allow the polyelectrolyte multilayers to be a good molecularly imprinted polymeric (MIP) system for large biomolecules. It is of interest from both a fundamental and technological standpoint to determine if the pores in the porous multilayer films can close with biomolecules or living cells trapped inside. The research will explore the possibilities to load biomolecules and cells into porous multilayer films, and the applications of these films in making MIPs and tissue engineering.

2) Smart Surfaces
Factors that determine the surface wettability are the surface roughness and surface chemical properties. The research aims at functionalizing the surfaces of porous multilayer structures with various molecules that can change their conformations with environmental stimuli such as temperature and electrical potential, immobilizing gold nanoparticles inside porous structures, and modulating local temperature changes with incident lasers. Our goal is to build surfaces that are able to switch from superhydrophilicity to superhydrophobicity by temperature, an incident laser or an electrical field. By incorporating the patterning technique that we have developed, we will also explore the fabrication of switchable microfluidic devices and microarrays for sensing.

3) Conductive Polymer Nanowires and Composites
The major research themes in molecular electronics are the construction of electronic circuits in which molecular systems act as connection elements, measurement and understanding of their voltage-current response. The research aims at the construction of nanojunctions containing gold nanoparticles and conductive polymers and the measurement of the charge transport of these nanojunctions using ultrahigh vacuum scanning tunelling spectroscopy (UHV-STS).

Selected Publications

1. Zhai, L.; Cebeci, F.; Cohen, R. E.; Rubner, M. F. "Stable Superhydrophobic Coatings from Polyelectrolyte Multilayers " Nano Lett. 2004, 7, 1349.

2. Zhai, L.; Nolte, A. J.; Rubner, M. F.; Cohen, R. E. " pH-gated Nanoporous Transitions of Polyelectrolyte Multilayers in Confined Geometries and Their Application as Tunable Bragg Reflectors" Macromolecules 2004, 37, 6113.

3. Zhai, L.; McCullough, R. D. " Regioregular Polythiophene / Gold Nanoparticle Hybrid Materials" J. Mater. Chem. 2004, 14, 141.

4. Zhai, L.; Laird, D. W.; McCullough, R. D. " Soft-lithography Patterning of Functionalized Regioregular Polythiophenes" Langmuir 2003, 19, 6492.

5. Zhai, L.; Pilston, R. L.; Zaiger, K. L; Stokes. K. K.; McCullough, R. D.; "Synthesis of Poly(3-(6-bromohexyl)thiophene) by Grignard Metathesis, and its Post- polymerization Functionalization." Macromolecules 2003, 36, 61.

6. Zhai, L.; McCullough, R. D. "Layer-by-layer Assembly of Polythiophene" Adv. Mater. 2002, 14, 901.

Graduate Students

The graduate students will be part of a new group, situated in a brand new laboratory, pursuing exciting projects in an interdisciplinary field of chemistry, physics, biology and nanoscience. They will receive a highly interdisciplinary education covering topics ranging from polymer synthesis to device physics. The future success of many emerging technologies currently under development in this country clearly depends on an expanded work force of such diverse scientists.