Background:

• 2003 MRS Graduate Student Gold Award, American Materials Research Society
• 2002 Technology Transfer Award, US Department of Energy, Lawrence Berkeley National Laboratory, Berkeley, CA, USA

Research in the Li group focuses on the synthesis, characterization, and application of self-assembled heterostructures. The overall goal is to develop bottom-up approaches for the manufacture of multi-component functional devices and to understand their structure-property relation. Using principles and tools developed in inorganic, organic, and physical chemistry, we aim to control the interfacing of various nanometer-scale components, so that the properties of individual components (such as inorganic nanoparticles, metal complexes, and organic semiconductors) as well as the processes occurring at their interfaces (such as charge or energy transfer) can be utilized efficiently to fabricate devices on large scales.

Templated Synthesis of Complex Nanostructures

Organic molecules have versatile self-assembly properties and form well-defined structures, such as vesicles, nanofibers, and nanotubes that bridge molecular scale with micron scale. In our research, organic self-assembled systems are designed to be structurally robust and chemically tolerant, so that they can be used as templates for synthesis of complex nanostructures. In particular, we design synthetic molecules containing multiple biological building blocks that can self-assemble in organic solvents, which vastly expands the accessibility of these self-assembled templates to various chemical reactions and species.

Supramolecular Chemistry of Inorganic Nanocrystals

Inorganic nanocrystals, with a wide range of optical, electronic, or magnetic properties, have been a subject of intensive research activities. In order to effectively apply their properties in the fabrication of devices, such as solar cells or magnetic storage media, it is necessary to make multi-component systems with their positional and orientational arrangement accurately controlled. For this aspect of our research, concepts developed in supramolecular chemistry will be used to direct nanocrystal interactions and their consequent assembly.

Selected Publications:

L.-S. Li, S. I. Stupp, "One-dimensional Assembly of Lipophilic Inorganic Nanoparticles Templated by Peptide-Based Nanofibers with Binding Functionalities", Angew. Chem. Int. Ed. 44, 1833 (2005).

L.-S. Li, M. Marjanska, G. H. J. Park, A. Pines, A. P. Alivisatos, "Phase diagram of solution of

CdSe nanorods", J. Chem. Phys. 120, 1149 (2004).

L.-S. Li, A. P. Alivisatos, "Origin and scaling of the permanent dipole moment in CdSe nanorods", Phys. Rev. Lett. 90, Art. 097402 (2003).

L.-S. Li, J. Walda, L. Manna, A. P. Alivisatos, "Lyotropic liquid crystalline phase of CdSe quantum rod solution", Nano Letters 2, 557 (2002) (cover article).

L.-S. Li, J. T. Hu, W. D. Yang, A. P. Alivisatos, "Band gap variation of size- and shape-controlled colloidal CdSe quantum rods", Nano Letters 1, 349 (2001).

J. Hu, L.-S. Li, W. D. Yang, L. Manna, L. W. Wang, A. P. Alivisatos, "Linearly polarized emission from colloidal semiconductor quantum rods", Science 292, 2060 (2001).