Abstract

Inorganic nanoparticles (NPs) have the ability to self-organize into variety of structures. Analysis of experimental data for different types of NPs indicates a general trend of self-assembly under a wider range of conditions and having broader structural variability than self-assembling units from organic matter. Remarkably, the internal organization of self-assembled NP systems rival in complexity to those found in biology which reflects the biomimetic behavior of nanoscale inorganic matter. In this talk, I will address the following questions:

(a)   What are the differences and similarities of NP self-organization compared with similar phenomena involving organic and biological building blocks?

(b)   What are the forces and related theoretical assumptions essential for NP interactions?

(c)   What is the significance of NP self-assembly for understanding emergence of life?

(d)   What are the technological opportunities of NP self-organization?

Self-organization of chiral nanostructures will illustrate the importance of subtle anisotropic effects stemming from collective behavior of NPs and non-additivity of their interactions. The fundamental significance of studies in this area from this and other groups will be discussed in relation to the origin of homochirality on Earth and spontaneous compartmentalization (protocells). The practicality of self-organization of nanoparticles will be discussed in relation to charge storage technologies, DNA/protein biosensing, chiral catalysis, and polarization-based optical devices.

References

1. Tang, Z.; Kotov, N. A.; Giersig, M. Spontaneous organization of single CdTe nanoparticles into luminescent nanowires, Science, 2002, 297, 237. 
2. Kotov, N. A. Inorganic Nanoparticles as Protein Mimics, Science, 2010, 330(6001), 188–189.
3. Srivastava S.; et al., Light-Controlled Self-Assembly of Semiconductor Nanoparticles into Twisted Ribbons, Science, 2010, 327, 1355.
4. Yeom, J.; et al., Chiral Templating of Self-Assembling Nanostructures by Circularly Polarized Light, Nature Mater. 2015, 14, 66.
5. Batista-Silvera, C.; Larson, R.; Kotov, N. A. Non-Additivity of Nanoparticle Interactions, Science, 2015, DOI: 10.1126/science.1242477.
6. L.Liu, et al. Low-Current Field-Assisted Assembly of Copper Nanoparticles for Current Collectors, Faraday Disc. 2015, 181, 383-401.
7. M. Yang, H. Chan, G. Zhao, J.H. Bahng, P. Zhang, P. Král, N.A. Kotov, Self-Assembly of Nanoparticles into Biomimetic Capsid-Like Nanoshells, Nature Chemistry, 2016, 9, 287–294.
8. J. H. Bahng, B. Yeom, Y. Wang, S. O. Tung, N.A. Kotov, Anomalous Dispersions of Hedgehog Particles, Nature, 2015, 517, 596–599.
9. W. Feng, J.-Y. Kim, et al. Assembly of Mesoscale Helices with Near Unity Enantiomeric Excess and Light-Matter Interactions for Chiral Semiconductors, Science Advances, 2017, 3(3), e1601159.
10. S. Jiang, et al.  Chiral Ceramic Nanoparticles of Tungsten Oxide and Peptide Catalysis, Journal of the American Chemical Society, 2017, JACS.7b01445 on the web.

Presenter

Nicholas A. Kotov

University of Michigan

Prof. Nicholas Kotov is working on chemistry, physics, materials science and technical realizations of biomimetic nanostructures. Conceptual examples of biomimetic nanostructures associated with his works include nacre-like layered nanocomposites, protein-mimetic self-organizing nanoparticles, virus-like supraparticles, chiral nanomaterials, and hedgehog colloids. His contribution to science include pioneering layered graphene nanocomposites, nanoparticle superlattices, nanostructured biocomposites (nacre, enamel, soft tissues), chiral nanoassemblies, and omni-dispersible colloids. Prof. Kotov is a founder of several start-up companies including Nico Technologies, 3D Biomatrix, Elegus Technologies that commercialized biomimetic nanomaterials for military, biomedical and energy storage technologies.