Shanju Zhang

Research Scientist

Office: 226 Mason Lab

Phone: (203) 436-4085
   

B.Sc. in Polymer, Department of Chemistry, Jilin University, China, 1993

Ph.D. in Polymer, Department of Chemistry, Jilin University, China, 1998

I joined the Osuji lab in October 2009 as a research scientist. Before, I worked as an assistant professor at Changchun Institute of Applied Chemistry at the Chinese Academy of Sciences (1998-2000), as a postdoctoral fellow at Johannes Gutenberg University of Mainz (Germany) (2000) and at Technical University of Berlin (Germany) (2000-2002), as a research associate in the Cavendish laboratory and Materials Science department at University of Cambridge (England) (2002-2006), and as a research scientist at Georgia Institute of Technology (2006-2009). I received an Alexander von Humboldt Research Fellowship in 2000. My research interest is in the area of synthesis, structural analysis and micro-processing of polymers and nanocomposites. I have published 50+ peer reviewed journal articles and held one British patent. I serve as a referee for 17 prestigious journals including Advanced Materials, Small, Polymer and Soft Matter. I have served as a member of the review panel for NSF.

maybe my walk is not so random

Conjugated (semiconducting) polymers as a competitive solar technology are promising for cost-effective, renewable energy sources. Our current project is focused on ordered nanostructures of conjugated polymers for high efficiency solar cells. A highly optimized layout for solar cells is represented by the so-called ordered bulk heterojuction (OBH) device, which features a vertically aligned (columnar) periodic nanostructure (Figure 1A). Our goal is the realization of this structure in hybrid organic-inorganic solar cells. We are interested in self-assembly of conjugated polymers in columnar liquid crystalline phases (Figure 2B) as one possible route to the realization of this device structure. Under external fields such as a magnetic field, the columnar nanodomains are aligned into ordered nanostructures. Hairy-rod polymers are promising for stabilizing columnar liquid crystals. By tailoring side-chain length and chemical structure, we are able to create columnar liquid crystals in hairy-rod conjugated polymers. Particular attentions are paid to nanodomain alignments and corresponding device performance.

The alternative for creating ideal OBH is infiltration of conjugated polymer solution or melt into a nanoporous inorganic semiconductor (Figure 2). Due to the geometric confinements, the infiltrated polymer forms ordered crystalline aggregates. At a molecular level, polymer chains are oriented along the channel direction. The resultant aligned nanostructures help accelerate hole mobility. Such ordered hybrid nanostructures provide a straightforward pathway for electron transport and electron collection. We are interested in the effect of the nanopore size on changes in polymer chain conformation, chain packing and hole mobility. Particularly, we pay attention to the relationship between the polymer nanostructures and device performance.

I was involved in various projects of polymers, including liquid crystalline polymers, block copolymers, conjugated polymers, biopolymers, polyolefin, high performance thermoplastics, and carbon nanotubes. My background is in Chemistry. I have also taken training on soft matter physics and polymer engineering. My work experience brings to the research a very unique blend of chemistry, physics and materials insights. Recent research highlights are shown as follows:

•  Discovered the world's first evidence of polymer transcrystallinity induced by carbon nanotubes.

•  Invented liquid crystal routes for carbon nanotube purification, fiber spinning and thin film fabrication.

•  Developed a novel micro-processing technique for spinning strong carbon nanotube fibers and sheets.

•  Developed a nano-decoration technique for imaging molecular trajectories in 2D liquid crystals.

•  Discovered a generic method for synthesis of ellipsoidal polymer colloids templated by nanoparticles.

Top: transparent carbon nanotube sheets by dry-drawing . Middle: polymer transcrystals with nanotubes (left); aligned nanotube - polymer hybrids (middle); liquid crystal ring of nanotubes (right). Bottom: bio- liquid crystal colloids (left); nanowire-nanotube assembly (middle); ellipsoidal polymer colloids (right)

20 selected publications:

•  S. J. Zhang , Q. W. Li, I. A. Kinloch, A. H. Windle, "Ordering in a droplet of an aqueous suspension of single-wall carbon nanotubes on a solid substrate", Langmuir, 2010, 26, 2107-2112.

•  W. Lin, K. S. Moon, S. J. Zhang, Y. Ding, Z. L. Wang, J. T. Shang, R.W. Zhang, M. X. Chen, C. P. Wong, "Microwave makes carbon nanotubes less defective", ACS Nano, 2010, 4, 1716-1722.

•  S. J. Zhang, L. B. Zhu, C. P. Wong, S. Kumar, "Polymer-infiltrated carbon nanotube fibers by in-situ polymerization", Macromolecular Rapid Communications , 2009, 30, 1936-1939.

•  S. J. Zhang, S. Kumar, "Carbon nanotubes as liquid crystals", Small , 2008, 4: 1270-1283. (Invited review article) . (Top 3 most accessed article)

•  S. J. Zhang , K. K. K. Koziol, I. A. Kinloch, A. H. Windle, "Macroscopic fibers of well-aligned carbon nanotubes by wet coagulation" Small 2008, 4: 1217-1222.

•  S. J. Zhang, S. Kumar, "Shaping polymer particles by carbon nanotubes", Macromolecular Rapid Communications 2008, 29: 557-561.

•  S. J. Zhang, M. L. Minus, L. B. Zhu, C. P. Wong, S. Kumar, "Polymer transcrystallinity induced by carbon nanotubes", Polymer 2008, 49:1356-1364.

•  S. J. Zhang, L. B. Zhu, M. L. Minus, H. G. Chae, S. Jagannathan, C. P. Wong, J. Kowalik, L. Roberson, S. Kumar, "Solid-state spun fibers from 1-mm high carbon nanotube forest synthesized by water-assisted chemical vapor deposition" Journal of Materials Science 2008, 43: 4356-4362.

•  S. J. Zhang , I. A. Kinloch, A. H. Windle, "Mesogenicity drives fractionation in lyotropic aqueous suspensions of multiwall carbon nanotubes" Nano Letters 2006, 6: 568-572.

•  S. J. Zhang , E. M. Terentjev, A. M. Donald, "Optical microscopy study for director distortions around the disclinations in side-chain liquid crystalline polymer films" Journal of Physical Chemistry B 2005, 109: 13195-13199.

•  S. J. Zhang , E. M. Terentjev, A. M. Donald, "Phase separation and organization of colloidal spheres suspended in sheared lyotropic liquid-crystalline biopolymers" Macromolecular Rapid Communications 2005, 26: 911-914.

•  S. J. Zhang , E. M. Terentjev, A. M. Donald, "AFM study for supermolecular microstructures in polymer thin films" Langmuir 2005, 21: 3539-3543.

•  S. J. Zhang , E. M. Terentjev, A. M. Donald, "Nature of disclination cores in liquid crystals" Liquid Crystals 2005, 32: 69-75.

•  S. J. Zhang , E. M. Terentjev, A. M. Donald, "Disclinations and their interactions in side-chain liquid crystalline polymer films" Macromolecules 2004, 37: 390-396.

•  B. Zhang, S. J. Zhang , L. Okrasa, T. Pakula, T. Stephan, M. Schmidt, "Synthesis and solid state structures of macromolecular cylindrical brushes with varying side chain length" Polymer 2004, 45: 4009-4015.

•  S. J. Zhang , L. X. Fu, J. Zhang, J. J. Liu, D. C. Yang, J. J. Ge, C. Y. Li, S. Z. D. Cheng, "Ordering-induced micro-bands in thin films of a main-chain liquid crystalline chloro-poly(aryl ether ketone)" Polymer 2004, 45: 3967-3972.

•  S. J. Zhang , E. M. Terentjev, A. M. Donald, "Stripe instability in thin films of smectic liquid crystalline polymers" European Physical. Journal E-Soft Matters 2003, 11: 367-374.

•  J. Zhang, L. X. Fu, S. J. Zhang , D. C. Yang, "Molecular lattice resolution of single faceted crystals of a thermotropic liquid crystalline poly(aryl ether ketone) using atomic force microscope (AFM)" Macromolecular Rapid Communications 2000, 21: 313-1316. (Cover Story)

•  S. J. Zhang , L. X. Fu, D. C. Yang, Z. H. Gao, M. J. Jia, Y. B. Zheng, Z. W. Wu, "Synthesis and thermotropic liquid crystalline behavior of the novel poly(aryl ether ketone)s with a methoxy group" Macromolecular Chemistry and Physics 2000, 201: 649-655.

•  S. J. Zhang , D. C. Yang, S. Z. D. Cheng, Y. B. Zheng, Z. W. Wu, R. Yosomiya, "Novel poly(aryl ether ketone)s exhibiting liquid crystallinity" Acta Polymeric 1998, 49 : 198-200.