Moonsub Shim

Moonsub Shim received his B.S. degree from the University of California at Berkeley in 1997 and his Ph.D. degree from the University of Chicago in 2001. After working as a postdoctoral researcher at Stanford University , he joined the faculty of the Department of Materials Science and Engineering at UIUC in 2002.

Whether it is a solid state or a soft condensed matter, nanometer length scale imparts extraordinary properties in materials. From unusual surfaces and interfaces to tunable electronic structure, nanoscale materials present a unique opportunity to explore novel phenomena in a size regime where neither atomic nor bulk description alone can satisfactorily explain and predict. Miniaturization of electronics beyond current semiconductor technology, efficient and clean energy source/conversion systems, and next-generation biomedical probes can all be envisioned with the new properties observed in nanoscale materials. Our research aim is to establish a broad understanding of nanoscale interfaces and how properties evolve as individual low dimensional materials are brought together to form sophisticated structures. Our interests span a wide range of disciplines from chemical synthesis and physical characterization of individual nanoscale materials to design and fabrication of nanoelectronic probes to elucidate biological processes.

Given specific components, whether they are carbon nanotubes, semiconductor nanocrystals or biologically relevant molecules, what the overall or the collective behavior of an organized ensemble will be is a question that requires an intimate knowledge of the interfaces of these nanometer scale materials. Can we amplify unique properties or induce new ones in creating novel architectures of nanoscale materials? Especially in heterogeneous systems composed of nanoscale materials of different composition, complexities at the surfaces and interfaces can quickly arise. However, these complexities can lead to unexpected properties and therefore new application prospects. The key to unlock the main factors that determine the collective properties lies in understanding and manipulating not only the individual isolated components but also their interfaces. We start with semiconductor nanocrystals and carbon nanotubes as prototypical zero- and one-dimensional systems to build higher dimensional hybrid materials with desired attributes.

There is a strong interplay between chemical synthesis and experimentation in our research efforts. New materials synthesis is designed to yield desired physical properties. Physical studies such as optical/infrared spectroscopy, microscopy and multi-probe electrical transport measurements in turn guide the fine-tuning of the synthesis and fabrication. It is also this combination of synthesis and characterization that will play a crucial role in developing new methods of building complex yet controlled architectures of nanoscale materials where we anticipate materials properties to be tunable from the inside-out (by changing chemical composition of nanoscale components) as well as outside-in (by changing the interfaces and/or the surrounding medium).

Selected Publications

“Functionalization of Carbon Nanotubes for Biocompatibility and Bio-Molecular Recognition,” M. Shim, N. Wong Shi Kam, R. J. Chen, Y. Li, and H. Dai, Nano Lett., 2, 285 (2002). [ pdf ]

“Polymer Functionalization for Air-Stable n-Type Carbon Nanotube Field-Effect Transistors,” M. Shim, A. Javey, N. Wong Shi Kam and H. Dai, J. Am. Chem. Soc. 123, 11512 (2001). [ pdf ]

“Doping and Charging in Semiconductor Nanocrystals,” M. Shim, C. Wang, D. J. Norris and P. Guyot-Sionnest, MRS Bulletin 26, 1005 (2001). [ pdf ]

“Electrochromic Nanocrystal Quantum Dots,” C. Wang, M. Shim and P. Guyot-Sionnest, Science 291, 2390 (2001). [ pdf ]

“Intraband Hole Burning in Colloidal Quantum Dots,” M. Shim and P. Guyot-Sionnest, Phys. Rev. B. 64, 245342 (2001). [ pdf ]

“Charge-tunable Optical Properties in Colloidal Semiconductor Nanocrystals,” M. Shim, C. Wang and P. Guyot-Sionnest, J. Phys. Chem. B 105, 2369 (2001). [ pdf ]

“N-Type Colloidal Semiconductor Nanocrystals,” M. Shim and P. Guyot-Sionnest, Nature, 407, 981 (2000). [ pdf ]

“Permanent Dipole Moment and Charges in Colloidal Quantum Dots,” M. Shim and P. Guyot-Sionnest, J. Chem. Phys. 111 , 6955 (1999). [ pdf ]